Search

[Purpose/Significance] Identifying potential technological opportunities will help countries and enterprises seize scientific and technological opportunities, which is particularly important for innovation entities to enhance their core competitiveness and gain competitive advantages in scientific and technological innovation and application. A systematic review of existing research is provided on technology opportunity identification, discriminating current limitations and research prospects to provide theoretical support for further research and practice on technology opportunity identification. [Method/Process] This paper first clarifies the connotation and types of technology opportunities, and the research holds that technology opportunities can be divided into three types: emerging technology, blank technology and fusion technology. It then sorts out the research status of three different types of technology opportunity identification at home and abroad through literature review, and focuses on the summary of the characteristics of different types of technology opportunity identification. It includes the core ideas, main methods, representative literature, and each type of data sources, and evaluates the existing research results. Finally, the limitations of the current research, and the development direction of future are discussed. [Results/Conclusions] Diversified types of technology opportunity identification are found and rich research methods are used in the literature, and a relatively standardized and systematic research paradigm has come into being. By analyzing each type of technology opportunity, some common elements can be found, including representative methods, method principles, data sources, knowledge representation units, technology opportunity definitions, technology opportunity evaluation, advantages and disadvantages, and other characteristics. The main limitations of the existing research are summarized as follows. First, the existing research is primarily carried out from a single perspective view, and a complete system of cross-domain technology identification and reference methods has not yet been formed. Second, in terms of data sources, most of the data sources of technology opportunity identification are papers or patent data, and there is a lack of research on the integration of multi-source data and study on multiple relationships. In terms of identification methods, the representative technology is primarily at a macro or micro level, and the semantic relationship between words is seldom considered. Finally, in terms of post-evaluation, there is a lack of a comprehensive and systematic evaluation system. The possible research work in the future may focus on the following aspects: cross-field and cross-topic technology opportunity identification to achieve cross convergence among more technology elements will become the development trend; more diversified and targeted data sources, research methods, and research content are expected; the analysis framework and process will be more standardized, and the post-evaluation system will be improved.

Objective To investigate the histological damage recovery of temporomandibular joint condylar cartilage caused by chronic unpredictable moderate stress, aiming to provide an experimental basis for the prevention and treatment of temporomandibular disorder. Methods This animal experiment was approved by the Laboratory Animal Ethical Inspection, School of Stomatology, The Fourth Military Medical University (No. 2020081). 60 male SD rats were randomly divided into control group, stress group, and 2-, 4- and 8-week post-stress recovery groups. Rats were subjected to chronic unpredictable moderate stress (CUMS) for 8 weeks including damp sawdust for 24 hours, tilted cage for 12 hours, noise for 4 hours, light/dark cycle reversal, water immersion, tail clamp, and restraint stress. The serum assessment, behavioral tests, histological and ultrastructural observation were performed 2-, 4- and 8-weeks after stress factors were removed. Serum levels of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were determined with ELISA. The sucrose preference test (SPT) and the forced swim test (FST) were used to assess the depressive-like behavior. The expression level of interleukin-1α (IL-1α) and matrix metalloproteinases-3 (MMP-3) were determined by Immunohistochemistry and Western blot. Results At the end of 8 weeks of CUMS, the serum levels of CORT and ACTH were significantly higher in stress group compared with control group (P0.05) and higher expression of MMP-3 comparing with the control group (P0.05). The condylar collagen fibers increased and showed a corrugated pattern, and no serious subchondral bone damage as well as irreversible damage occurred. Both of the expression levels of IL-1α and MMP-3 approached those of the control group after 8 weeks of stress removal (P>0.05). Conclusion The behavioral changes and condylar cartilage damage caused by CUMS could be self-repaired. The decline in IL-1α and MMP-3 expression may be one of the intrinsic mechanisms of this self-repair process.

Supercapacitor is an important energy storage device widely used in the automobile industry, military production, and communication equipment because of its fast charge‐discharge rate, and high power density. Herein, carbon quantum dots modified and Y3+ doped Ni3(NO3)2(OH)4 (NiY@CQDs) nanospheres are prepared by a solvothermal method and used as an electrode material. The electrochemical properties of NiY@CQDs were measured in a three‐electrode system. An asymmetric supercapacitor (ASC) cell was assembled with activated carbon (AC) as the anode and NiY@CQDs as the cathode. The electrochemical properties of the ASC device were measured in a two‐electrode system. Experimental results show the shape of NiY@CQDs is petal‐shaped and the introducing carbon quantum dots and doping Y3+ significantly increases the specific surface area, conductivity, and specific capacitance of Ni3(NO3)2(OH)4. The mass‐specific capacitance of NiY@CQDs reaches up to 2944 F g−1 at a current density of 1 A g−1. The asymmetric supercapacitor of NiY@CQDs//AC has a high energy density of 138.65 Wh kg−1 at a power density of 1500 W kg−1, displaying a wide range of application prospects in the energy storage area. [ABSTRACT FROM AUTHOR]

Metal–organic framework compounds are extensively utilized in various fields, such as electrode materials, owing to their distinctive porous structure and significant specific surface area. In this study, NiCoAl-MOF metal–organic framework precursors were synthesized by a solvothermal method, and NiAl2O4/NiCo2O4 electrode materials were prepared by the subsequent calcination of the precursor. These materials were characterized by XRD, XPS, BET tests, and SEM, and the electrochemical properties of the electrode materials were tested by CV and GCD methods. BET tests showed that NiAl2O4/NiCo2O4 has an abundant porous structure and a large specific surface area of up to 105 m2 g−1. The specific capacitance of NiAl2O4/NiCo2O4 measured by the GCD method reaches up to 2870.83 F g−1 at a current density of 1 A g−1. The asymmetric supercapacitor NiAl2O4/NiCo2O4//AC assembled with activated carbon electrodes has a maximum energy density of 166.98 W h kg−1 and a power density of 750.00 W kg−1 within a voltage window of 1.5 V. In addition, NiAl2O4/NiCo2O4 materials have good cycling stability. These advantages make it a good candidate for the application of high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

It is shown that the uniform radius of spatial analyticity σ (t) of solutions at time t to the Ostrovsky equation with positive dispersion cannot decay faster than | t | − 4 3 as | t | → ∞ given initial data that is analytic with fixed radius σ 0 . The main ingredients in the proof are almost conservation law for the solution to the Ostrovsky equation in space of analytic functions and space-time dyadic bilinear estimates associated with the Ostrovsky equation. [ABSTRACT FROM AUTHOR]