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关键词： TANK结合激酶1(TBK1)   核因子κB激活激酶   CiteSpace   Web of Science   文献计量学   可视化   共被引   研究热点   前沿  

摘要： 背景:肿瘤双向调控因子核因子κB激活激酶的研究成果逐年增多,但是却没有相关文献计量学分析。目的:通过文献计量学分析肿瘤逃避因子核因子κB激活激酶的研究现状、热点及趋势。方法:基于Web of Science核心合集中的SCIE数据库筛选近10年来核因子κB激活激酶相关研究文献,导入Cite Space 6.3.R1软件中分别以国家(地区)、作者、机构、参考文献和关键词5个选项进行文献计量及可视化分析,并运用Origin 2021软件绘制相关统计图。结果与结论:核因子κB激活激酶的发文量、文献共被引次数呈现上升的趋势,Chen,Dan-Dan、Gui,Jian-Fang、Qin,Qiwei和Li,Shun 4位作者发文量最多(11篇),中国科学院、中国科学院大学、浙江大学、中国农业科学院、武汉大学的发文量较大(>50篇)。近10年来关于核因子κB激活激酶的研究热点主要集中在innate immunity、c GAS-STING pathway、NF-κB、inflammation、optineurin、expression、cancer等模块。结果表明,近年来各国学者在相关领域进行了持续且深入的研究,核因子κB激活激酶在自身免疫系统、信号通路、基因表达、肿瘤防治等方面显示出巨大的科研潜力。但是学者之间、机构之间的学术合作并不紧密,今后学者应加强合作与交流,把握核因子κB激活激酶的研究热点与趋势,拓展在疾病领域中的研究范围,为进一步阐明疾病的药效机制和病理变化提供更多证据。

关键词： 4,4′,6,6′-tetra(azido)hydrazo-1,3,5-triazine   Adiabatic time-to-explosion   Combustion   High-nitrogen compounds   Thermal safety  

摘要： High-nitrogen compounds are promising energetic materials due to their high enthalpy of formation (${\Delta }_{\mathrm{f}}{H}_{\mathrm{m}}^{\theta }$) and environmentally friendly combustion products. However, the thermal decomposition kinetics, thermal safety and combustion behavior of 4,4′,6,6′-tetra(azido)hydrazo-1,3,5-triazine (TAHT) have not yet been systematically clarified.

关键词： Density functional theory   Flame retardant materials   Ionic liquids   Magnesium hydroxide nanoparticles  

摘要： In response to the growing demand for environmentally friendly and efficient flame retardants, nano-magnesium hydroxide (nano-MH) has emerged as a promising candidate due to its high thermal stability and smoke suppression properties. However, its practical application is limited by agglomeration and high loading requirements.

关键词： Keggin-型杂多阴离子   质子化结构   光谱性质   密度泛函理论   遗传算法  

摘要： Keggin-型杂多酸作为高效光催化剂在能源催化转换领域扮演重要角色.虽然在实验上利用它们较为容易实现光催化反应,然而要对相关的光催化反应机理进行原子水平细节研究仍然困难重重,在其中获得一个相对合理的催化剂团簇模型至关重要.本文利用自建的遗传算法程序并结合密度泛函理论探究Keggin-型铌杂多阴离子完全质子化团簇(H_(n+3)[PMo_(12-n)Nb_(n)O_(40)],n=1~4)的稳定几何结构与光谱性质.通过观察铌作为杂原子取代团簇表面上的钼以及质子占据对体系几何结构和光谱性质的影响,我们期望能够为基于该类团簇的光催化剂分子设计以及光催化反应机理探究提供有用信息.基于计算数据,我们发现:在优化团簇几何结构中,随着杂Nb原子数目的增多,它们在团簇骨架上的分布能展现一定的规律(倾向于离散分布或者共用O桥而成等边三角形),并且质子均倾向于与杂Nb原子(或其邻居)相联的端基O成单键.团簇体系的偶极矩从最大值出发降到最低值而后逐渐增大.这可以被归功于杂原子铌与被取代原子钼之间相对较小的电负性差异以及取代位置模式的不同.研究体系的红外(或拉曼)吸收主要分布在两个波数区间(0~1500 cm^(-1))以及(3600~4000 cm^(-1)).前者对应于团簇骨架上重原子间(桥基O-Mo,O-Nb等)或者骨架局部关联的振动模式,后者对应于端基的O-H单键的振动模式.同时,它们在1200~1500cm^(-1)波数区间展现可区分的红外吸收分布,在高波数区间Raman吸收可展现强度差异.

关键词： 1,4-butanediol   Cu catalysts   Dehydrocyclization   Spinel structure   γ-butyrolactone  

摘要： Gas-phase dehydrocyclization of 1,4-butanediol (BDO) is an environmentally benign and sustainable route for γ-butyrolactone (GBL) production. In this work, a series of Cu-M (M = Zn, Cr) catalysts was synthesized via coprecipitation and evaluated in a fixed-bed reactor for GBL yield. Under the reaction conditions of 240 °C, 0.1 MPa, and a weight hourly space velocity (WHSV) of 2 mL∙g⁻¹∙h⁻¹, 99.62% of BDO conversion, 99.72% of GBL selectivity, and 2.22 mol_GBL·g_catalyst^-1·h⁻¹ of CBL formation rate were achieved over CuZnCr-600 catalyst, which is higher than reported studies. Long-term test proved that this catalyst could operate over 100 h without any deactivation. Combined microscopic and spectroscopic analysis showed that the calcination conditions affected the surface acidity-basicity of catalysts by changing the CuO content and the strength of the Cr-O bond. The Cu-M compositions significantly influenced the morphology and the electronic properties of Cu species. The incorporation of Cr led to the formation of CuCr₂O₄ spinel structure, which not only enhanced Cu dispersion but also improved the catalysts’ resistance to sintering. The presence of Zn restrained the phase-transformation of CuCr₂O₄ from cubic to tetragonal, which ensured the reducible property of CuCr₂O₄ even under high-temperature calcination. Furthermore, modulating the calcination temperature and the Cu-M compositions maintained an optimal Cu⁺/Cu⁰ ratio under reaction conditions. All these issues contributed to the high yield of GBL and the prolonged lifetime of catalysts.

关键词： Nonrecurrent orbit   Hausdorff Dimension   Hausdorff Dimension   (-beta)-Transformation  

摘要： We investigate the size of the set of beta > 1 for which the orbits of 1 are nonrecurrent under the (-beta)-transformation T-beta. We prove that the set of beta > 1 with sup(n >= 1)T(-beta)(2n-1)(1) < 1 has Lebesgue measure 0. By constructing fractal sets in a neighborhood of an algebraic number beta > 1, we show that the set {beta is an element of (1,root 5 + 1/ 2) :sup(n >= 1)T(-beta)(n)(1) < 1} is of full Hausdorff dimension. The result of this paper significantly extends the related known result of beta-transformation and that of T-beta for beta >= root 5+1/ 2.

关键词： Atom probe tomography   Bubbles   CLF-1 steel   Cold work   Irradiation hardening   Nano-sized oxide particles   ODS steel  

摘要： Both uniformly dispersed nano-oxide particles and dislocations introduced by cold work are key approaches to enhancing the irradiation tolerance of materials. This study systematically investigates the irradiation responses of China Low-Activation Ferrite steel (CLF-1) steels (with 0 % and 10 % cold-work reductions, denoted as CW 0 % and CW 10 %) and oxide dispersion-strengthened (ODS) steel under sequential H⁺-(Fe²⁺+He⁺) irradiation at 350 °C and 450 °C. Microstructural evolution, including bubbles and dislocation loops, was characterized via transmission electron microscopy (TEM). And atom probe tomography (APT) elucidated the configuration of nano-sized oxide particles in ODS steel. At both irradiation temperatures, CW 10 % exhibited an increase in the number density of dislocation loops and bubbles but a decrease in average size compared to CW 0 %, attributed to the enhanced defect sinks induced by cold work. The analysis results of ODS steel based on APT indicate that the average size and number density of oxide particles are significantly dependent on the irradiation temperature, and the aggregation of Cr element was found in the oxide particles at both irradiation conditions, with slightly elevated levels observed at 450 °C compared to 350 °C. Notably, CW 10 % and ODS steel demonstrated comparable irradiation hardening resistance, rationalized by the similar strength of the primary sinks they introduced individually. The contributions of dislocation loops, bubbles, oxide particles, and dislocation lines to irradiation hardening are quantified using the Dispersed Barrier Hardening (DBH) model and Friedel-Kroupa-Hirsch (FKH) model. These results demonstrate that dislocations introduced by controlled cold working and dispersed nanoscale oxide particles of tailored size and density exert a comparable effect in mitigating irradiation hardening, which offers different promising pathways to improve the irradiation tolerance of advanc

关键词： 1,2-pentanediol   Catalytic hydrocracking   Furfural   Membrane dispersed microreactor  

摘要： The conventional production of 1,2-pentanediol (1,2-PeD) from fossil fuels suffers from high energy consumption and significant environmental pressure. Therefore, developing efficient catalysts to enable the hydrolytic hydrogenation of biomass-derived furfural (FF) is an urgent requirement for obtaining a green alternative. In this work, a membrane dispersion microreactor was successfully employed to incorporate Ce into a Cu-based catalyst for the catalytic hydro conversion of FF to 1,2-PeD. The optimum process conditions were determined by orthogonal reaction: 170 ℃, 6 MPa, 5.5 h. Under these conditions, FF was completely converted with the selectivity increased to 44%, resulting in a yield 2.2 times higher than that obtained with the undoped Ce catalyst. Furthermore, the catalyst exhibited excellent stability with no significant activity loss after five cycles of use. The characterization results show that the introduction of Ce significantly improved the dispersion of the active components, effectively suppressed the agglomeration of Cu particles, and increased the specific surface area of the catalysts; the calcination temperature changes the number of basic sites on the surface of the catalyst and affects the mode of adsorption of the intermediate furfuryl alcohol (FFA), thus affecting the catalyst performance.

关键词： OME   POMDME   MBMS   Flow reactor   Low-temperature oxidation   Kinetic modeling   NTC  

摘要： This study investigates the oxidation of three oxymethylene ethers (OME_1–3) in a new elevated-pressure laminar plug-flow reactor, utilizing electron-ionization molecular-beam mass spectrometry. Experiments were conducted at an absolute pressure of 5 bar to mimic conditions more relevant to combustion systems but still allowing for the exploration of reaction kinetics and pathways in a controlled environment. The experimental work is supported by kinetic modeling using our in-house DLR Concise mechanism to gain deeper insights into OME_1-3 combustion chemistry and highlight the controlling pathways. Kinetic modeling with two additional literature mechanisms was also employed to complement the findings. The measurements at constant carbon flow and similar conditions enable a systematic analogy among the three studied OMEs. The results reveal preferred formation of small C₁–C₂ hydrocarbons and oxygenates such as formaldehyde and methyl formate as combustion intermediates. Formation of methanol and formic acid was also observed during oxidation of all three OMEs, but the latter in significantly higher concentrations for both longer-chain OMEs. OME₁ shows only low reactivity in the low-temperature chemistry (LTC) regime, while the two larger OMEs have a higher reactivity in the LTC regime and also show a negative temperature coefficient behavior at the studied conditions. In line with previous reactor studies at atmospheric pressure, the reactivity of OME₂ and OME₃ is also similar at 5 bar, but is clearly distinguishable from OME₁. This work not only enhances our understanding of the fundamental chemistry underlying the oxidation mechanisms of OMEs, but also underscores their potential as cleaner fuel alternatives.