齿面点蚀是一种典型的行星齿轮系统故障。为识别点蚀状态,本文开展动力学特性研究并提出了一种新型的评估指标。首先,虑及过渡曲线和齿间结构耦合效应,利用改进Weber法建立了精确的含点蚀故障齿轮副啮合刚度模型,并研究了故障程度对啮...齿面点蚀是一种典型的行星齿轮系统故障。为识别点蚀状态,本文开展动力学特性研究并提出了一种新型的评估指标。首先,虑及过渡曲线和齿间结构耦合效应,利用改进Weber法建立了精确的含点蚀故障齿轮副啮合刚度模型,并研究了故障程度对啮合刚度的影响规律。然后,综合考虑时变啮合刚度、静态传动误差、齿侧间隙和时变振动传递路径等多种因素构建了行星齿轮系统平移-扭转动力学模型,揭示了点蚀程度对系统动态特性的影响规律,并基于振动信号频谱特点提出了边带能量因子(Sideband Energy Factor,SEF)用于损伤评估。最后,利用实验验证了仿真模型的正确性及所提指标的有效性。展开更多
Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and...Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and efficient electron transfer.Herein,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for photo-biocatalysis.With SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic systems.Since SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.展开更多
Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.Th...Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.The dataset is first preprocessed using solo thermal encoding and normalization functions.Then the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a classifier.It is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning models.The model uses a new neural network to achieve fast and accurate network traffic intrusion detection.The model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively.展开更多
Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental protection.Dye-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocataly...Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental protection.Dye-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocatalysis),but their performances are far lower than the plant photosystems,partially because of the incompatibility between dye and the protein matrix that limits excited state electron transfer of the included dyes.Here,using ThT-insulin amyloid assembly as a model system,we proposed that increasing the dye-protein compatibility could lead to the improved photo-biocatalytic performance.A ThT derivative,ThTPD,was designed with the same electron acceptor but extended π-conjugated donor structure.When integrated into the insulin amyloid,the extended π-conjugated donor structure allowed increased binding affinity and energy with the amyloid matrix,thus better electron transport to the mediator to drive the photocatalytic reaction.Meanwhile,compared with ThT, ThTPD exhibited improved light absorption and longer excited state lifetime.The photo-biocatalytic performance of ThTPD-insulin amyloid was greatly improved as compared with that of ThT in reduced nicotinamide adenine dinucleotide(NADH) regeneration.When integrating with NADH-dependent L-glutamate reductase,the efficiency of the ThTPD-insulin amyloid hybrid was 2.8-fold higher than that of ThT in glutamate generation,showing promising feature in biocatalytic solar-to-chemical conversion.展开更多
多种真菌多糖近年来因其免疫调节活性成为保健食品领域研究的热点。本实验以食药用真菌蛹虫草提取物蛹虫草多糖(Cordyceps militaris polysaccharides,CMP)为研究材料,初步探究CMP对小鼠巨噬细胞RAW264.7免疫活性的调节机制。噻唑蓝实...多种真菌多糖近年来因其免疫调节活性成为保健食品领域研究的热点。本实验以食药用真菌蛹虫草提取物蛹虫草多糖(Cordyceps militaris polysaccharides,CMP)为研究材料,初步探究CMP对小鼠巨噬细胞RAW264.7免疫活性的调节机制。噻唑蓝实验结果显示CMP无细胞毒性,且100、200μg/mL CMP可以明显增强RAW264.7细胞活性;中性红法、Griess法和酶联免疫吸附检测结果表明25～200μg/mL的CMP以剂量依赖方式增强RAW264.7细胞吞噬活性并增加一氧化氮(nitric oxide,NO)和白介素-1β(interleukin-1β,IL-1β)分泌,肿瘤坏死因子-α(tumor necrosisfactor-α,TNF-α)的分泌呈先升高后降低的趋势,在100μg/mL时达到最高值;抑制剂中和实验结果显示当Toll样受体4(Toll-like receptors 4,TLR4)和甘露糖受体(mannose receptor,MR)受到抑制时,CMP诱导的RAW264.7免疫反应显著降低,这表明TLR4和MR均为CMP激活巨噬细胞的受体;此外,Western blot结果显示丝裂原活化蛋白激酶(mitogen-activated protein kinases,MAPK)信号通路也参与CMP诱导的RAW264.7细胞分泌NO、TNF-α和IL-1β。表明TLR4和MR/MAPK信号传导途径在CMP诱导巨噬细胞RAW264.7产生免疫应答时发挥了重要作用。展开更多
文摘齿面点蚀是一种典型的行星齿轮系统故障。为识别点蚀状态,本文开展动力学特性研究并提出了一种新型的评估指标。首先,虑及过渡曲线和齿间结构耦合效应,利用改进Weber法建立了精确的含点蚀故障齿轮副啮合刚度模型,并研究了故障程度对啮合刚度的影响规律。然后,综合考虑时变啮合刚度、静态传动误差、齿侧间隙和时变振动传递路径等多种因素构建了行星齿轮系统平移-扭转动力学模型,揭示了点蚀程度对系统动态特性的影响规律,并基于振动信号频谱特点提出了边带能量因子(Sideband Energy Factor,SEF)用于损伤评估。最后,利用实验验证了仿真模型的正确性及所提指标的有效性。
基金the financial support from the National Natural Science Foundation of China (22274102 and 22325403)the Fundamental Research Funds from Sichuan University (2022SCUNL104)the Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(2022A02)
文摘Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable energy.It is thus important to develop light antennas with both good light har-vesting and efficient electron transfer.Herein,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for photo-biocatalysis.With SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic systems.Since SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.
基金the Gansu University of Political Science and Law Key Research Funding Project in 2018(GZF2018XZDLW20)Gansu Provincial Science and Technology Plan Project(Technology Innovation Guidance Plan)(20CX9ZA072).
文摘Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection model.The dataset is first preprocessed using solo thermal encoding and normalization functions.Then the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a classifier.It is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning models.The model uses a new neural network to achieve fast and accurate network traffic intrusion detection.The model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively.
基金financial support from the National Natural Science Foundation of China(22274102 and 22001182)the Sichuan Science and Technology Program(2022ZYD0027)+1 种基金the Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(2022A02)the Fundamental Research Funds for the Central Universities。
文摘Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental protection.Dye-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocatalysis),but their performances are far lower than the plant photosystems,partially because of the incompatibility between dye and the protein matrix that limits excited state electron transfer of the included dyes.Here,using ThT-insulin amyloid assembly as a model system,we proposed that increasing the dye-protein compatibility could lead to the improved photo-biocatalytic performance.A ThT derivative,ThTPD,was designed with the same electron acceptor but extended π-conjugated donor structure.When integrated into the insulin amyloid,the extended π-conjugated donor structure allowed increased binding affinity and energy with the amyloid matrix,thus better electron transport to the mediator to drive the photocatalytic reaction.Meanwhile,compared with ThT, ThTPD exhibited improved light absorption and longer excited state lifetime.The photo-biocatalytic performance of ThTPD-insulin amyloid was greatly improved as compared with that of ThT in reduced nicotinamide adenine dinucleotide(NADH) regeneration.When integrating with NADH-dependent L-glutamate reductase,the efficiency of the ThTPD-insulin amyloid hybrid was 2.8-fold higher than that of ThT in glutamate generation,showing promising feature in biocatalytic solar-to-chemical conversion.
