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1.
Extending visible light absorption range and suppressing the recombination of photogenerated charge carriers are always important topics in developing efficient solar-driven photocatalysts. In this study, the thermal treatment process at 400 °C in a high-pressure hydrogen atmosphere was applied to modify graphitic carbon nitride. Compared to the normal atmospheric hydrogen treatment process, this process has the merit of producing nitrogen deficient graphitic carbon nitride in high-yield. The optimal photocatalytic activity of modified graphitic carbon nitride was demonstrated by controlling the treatment duration in the hydrogen atmosphere.The changes in the crystal structure, microstructure and optical properties of carbon nitrides were investigated by several characterizations. The relationship between the photocatalytic activity and structures of graphitic carbon nitride was preliminarily established. The results obtained in this study could provide some new ways of improving the activity of graphitic carbon nitride based photocatalyst.  相似文献   
2.
The NLRP3 inflammasome is a critical innate immune pathway responsible for producing active interleukin (IL)-1β, which is associated with tumor development and immunity. However, the mechanisms regulating the inflammatory microenvironment, tumorigenesis and tumor immunity are unclear. Herein, we show that the NLRP3 inflammasome was over-expressed in human HNSCC tissues and that the IL-1β concentration was increased in the peripheral blood of HNSCC patients. Additionally, elevated NLRP3 inflammasome levels were detected in tumor tissues of Tgfbr1/Pten 2cKO HNSCC mice, and elevated IL-1β levels were detected in the peripheral blood serum, spleen, draining lymph nodes and tumor tissues. Blocking NLRP3 inflammasome activation using MCC950 remarkably reduced IL-1β production in an HNSCC mouse model and reduced the numbers of myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs) and tumor-associated macrophages (TAMs). Moreover, inhibiting NLRP3 inflammasome activation increased the numbers of CD4+ and CD8+ T cells in HNSCC mice. Notably, the numbers of exhausted PD-1+ and Tim3+ T cells were significantly reduced. A human HNSCC tissue microarray showed that NLRP3 inflammasome expression was correlated with the expression of CD8 and CD4, the Treg marker Foxp3, the MDSC markers CD11b and CD33, and the TAM markers CD68 and CD163, PD-1 and Tim3. Overall, our results demonstrate that the NLRP3 inflammasome/IL-1β pathway promotes tumorigenesis in HNSCC and inactivation of this pathway delays tumor growth, accompanied by decreased immunosuppressive cell accumulation and an increased number of effector T cells. Thus, inhibition of the tumor microenvironment through the NLRP3 inflammasome/IL-1β pathway may provide a novel approach for HNSCC therapy.  相似文献   
3.
Huang  Bai  Sun  Yuying  Wang  Shouyang 《系统科学与复杂性》2021,34(6):2219-2230
Journal of Systems Science and Complexity - This paper studies the estimation of the partially linear panel data models, allowing for cross-sectional dependence through a common factors structure....  相似文献   
4.
Traditional metal conductive fillers are expensive and prone to oxidation. Thus, the development of new conductive powders as fillers is urgently needed. A novel gaseous penetration technology was adopted to prepare La-doped medical stone powders(La-MSPs), which are inexpensive mesoporous materials, as a new kind of conductive filler material. The prepared La-MSPs attained a resistivity of 450 ?·m and were used as a filler to prepare conductive coatings with epoxy resin as the resin matrix. The influence of the La-MSPs dosage on the resistance and hardness of the coatings was also determined. The resistance and the hardness both decreased with increasing filler dosage. Finally, the optimum recipe of the conductive coatings with the most suitable fillers dosage(55 wt%) was obtained. The hardness and resistance of the coatings with 55 wt% La-MSPs were HV 4 and 5.5 × 10~7 ?, respectively.  相似文献   
5.
The amount of digital data is increasing every day. At every step of our daily lives, we deal with technologies in which our data are stored(e.g., mobile phones and laptops), and this is one of the main reasons for the design of various types of encryption and user identity verification algorithms. These algorithms are meant not only to fulfill the desire of protecting data but also to address the possibility of granting access of specific digital data to selected individuals. This process brings with it the problem of identity verification. This paper discusses the problem of voice verification and presents a voice verification method based on artificial intelligence methods.Numerous tests are performed herein to demonstrate the effectiveness of the presented solution. The research results are shown and discussed in terms of the advantages and disadvantages of the solution.  相似文献   
6.
Wu  Guangyu  Sun  Jian 《系统科学与复杂性》2019,32(5):1290-1305
In this article, an optimal switching integrity attack problem is investigated to study the response of feedback control systems under attack. The authors model the malicious attacks on sensors as additive norm bounded signals. The authors consider an attacker who is only capable of launching attacks to limited number of sensors once a time and changing the combinations of attacked sensors all over the time. The objective of this paper is to find the optimal switching sequence of these combinations and the optimal attack input. The authors solve this problem by transforming it into a traditional optimal control problem with new control variables vary continuously in the range [0, 1]. The optimal solutions of the new control variables are of bang-bang-type. Therefore, an algebraic switching condition and an optimal attack input can be obtained. Finally, numerical results are provided to illustrate the effectiveness of the methods.  相似文献   
7.
Li  Ting  Sun  Yao  Huang  Zhenyu  Wang  Dingkang  Lin  Dongdai 《系统科学与复杂性》2019,32(1):205-233
Journal of Systems Science and Complexity - The GVW algorithm is an efficient signature-based algorithm for computing Gröbner bases. In this paper, the authors consider the implementation of...  相似文献   
8.
This paper studies the existence and uniqueness conditions for the quaternion-valued nonlinear impulsive system. Firstly, a space of quaternion-valued piecewise functions is constructed and completeness of the space is also proved. Then by taking advantage of the Bielecki norm and fixed point theorem, existence and uniqueness criteria of quaternion-valued nonlinear impulsive system are obtained. At last, an example is given to illustrate our theoretical results.  相似文献   
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10.
专业化众创空间是在众创空间基础上发展起来的服务于产业细分领域、高度专业化、重点服务于实体经济的一种新型创新创业服务载体.北京市作为全国科技创新中心,创新创业高度活跃,专业化众创空间不断探索模式创新和服务创新,在服务高精尖产业发展、加快新旧动能转换、促进科技成果转化、盘活科技创新资源等方面发挥了重要作用.文章通过分析北京市专业化众创空间发展的情况和特点,总结提炼了几种典型发展模式,分析了专业化众创空间对首都经济高质量发展的重要意义,同时针对目前北京市专业化众创空间发展存在的主要问题,提出相关对策建议.  相似文献   
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