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FRACTAL ANALYSIS OF CATALYST NiO/α-Al2O3

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Journal of Energy Chemistry 1995年第4期 434-438页

作者： ZHOU Yong-Chao yu hua-Gen wang hua-Ming CHENG Ji-yuanChengdu Institute of Organic Chemistry, Academia Sinica Chengdu, Sichuan 610015

We found that the Freundlich formula H=kCcan be used todescribe the isothermal adsorption curve of support α-AlOwith fractalstructures in nickel nitrate *** n is relative to the surface fractaldimension D of α-AlO.

关键词： fractal adsorption dimension catalyst NiO/α-Al2O3

Brain-derived neurotrophic factor inducing angiogenesis through modulation of matrix-degrading proteases

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Chinese Medical Journal 2006年第7期119卷 589-595页

作者： SUN Chun-yan HU yu wang hua-fang HE Wen-juan wang Ya-dan WU Tao Institute of Hematology Union Hospital Tongji Medical CollegeHuazhong University of Science and Technology Wuhan 430022China

Background Recent studies have proved that brain-derived neurotrophic factor （BDNF） possesses angiogenic activity in vitro and in vivo. However, the proangiogenic mechanism of BDNF has not yet been provided with enough information. To explore the proangiogenic mechanism of BDNF, we investigated the effects of BDNF on extracellular proteolytic enzymes, including matrix metalloproteinases （MMPs） and serine proteases, particularly the urokinase-type plasminogen activator （uPA）-plasmin system in human umbilical vein endothelial cells （HUVECs） model.Methods Tube formation assay was performed in vitro to evaluate the effects of BDNF on angiogenesis. The HUVECs were treated with various concentrations of BDNF （25-400 ng/ml） for different （6-48 hours）, reverse transcriptase-polymerase chain reaction （RT-PCR） was used to assay MMP-2, MMP-9, TIMP-1, and TIMP-2 mRNA in HUVECs, and the conditioned medium was analyzed for MMP and uPA activity by gelatin zymography and fibrin zymography, respectively, uPA, plasminogen activator inhibitor （PAI）-1, tissue inhibitors of metalloproteinase （TIMP）-1, and TIMP-2 were quantified by western blotting analysis.Results BDNF elicited robust and elongated angiogeneis in two-dimensional cultures of HUVECs in comparison with control. The stimulation of serum-starved HUVECs with BDNF caused obvious increase in MMP-2 and MMP-9 mRNA expression and induced the pro-MMP-2 and pro-MMP-9 activation without significant differences in proliferation. However, BDNF had no effect on TIMP-1 and TIMP-2 production. BDNF increased uPA and PAI-1 production in a dose-dependent manner. Maximal activation of uPA and PAI-1 expression in HUVECs was induced by 100 ng/ml BDNF, while effects of 200 ng/ml and 400 ng/ml BDNF were slightly reduced in comparison with with those of 100 ng/ml. Protease activity for uPA was also increased by BDNF in a dose-dependent manner. BDNF also stimulated uPA and PAI-1 production beyond that in control cultures in a time-dependent man

关键词： brain-derived neurotrophic factor angiogenesis extracellular proteolytic enzyme

STUDY ON TPR OF NICKEL OXIDE CATALYSTS CALCINED AT HIGH TEMPERATURES

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Journal of Energy Chemistry 1995年第1期 113-118页

作者： GAO Xiang CHENG Ji-yuanFU Xi-yu wang hua-MingChengdu Institute of Organic Chemistry, Academia Sinica Chengdu,Sichuan 610015

TPR technique has been used, to investigate the reducibilities of three types of nickel oxide catalysts calcined in air between 650℃and 1050℃: NiO/Al2O3, NiO/MgAl2O4and NiO/(CaO, MgO) · A12O3· xSiO2. The results indicate that the TPR peaks of all the catalysts were shifted toward high temperature and peak areas were gradually reduced with increasing calcination temperature. Particularly, the main TPR peaks almost disappeared at 1050℃-It was also observed that NiO/(CaO, MgO)· Al2O3 · xSiO2 catalyst was the easiest to be reduced of these catalysts, and there was a small shoulder peak before the main peak for each catalyst. Examination of these catalysts by XPS showed that there were two forms of nickel oxides on support surface .

关键词： TPR nickel oxide catalyst calcination

Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： Yan-Heng yu Sai wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

Biological Evaluation of α-TCP/TTCP Composite Bone Cement

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Journal of Wuhan University of Technology(Materials Science) 2002年第3期17卷 35-38页

作者：戴红莲 WuhanUniversityofTechnology

tricalcium phosphate(α TCP)/tetracalcium phosphate(TTCP) composite bone cement had good hydration *** our system,α TCP/TTCP powder mixture was mixed with water at a powder/liquid (P/L) ratio of 1.50g·mL -1 .The setting time could be adjusted,the maximum compressive strength was 45.36MPa,and the hydration product was hydroxyapatite (HAP).In vitro biological simulated experiments indicate that α TCP/TTCP bone cement has α certain *** hardened product is mainly HAP after soaking in simulated body fluid (SBF) for 10 *** results of in vitro test and animal experiments and SEM analyses show that no local or general toxicity response,no muscle stimulation,no haemolysis,no cruor,no inflammatory reaction and no exclusion response are caused by α TCP/TTCP cement, which can be contributed to bone tissue spreading and impinging.α TCP/TTCP cement hydrated and hardened continually in *** materials fused with host bone together with implanting time ***,it is believed that α TCP/TTCP composite bone cement has a high biocompatibility and bioactivity,a certain biodegradation and good osteogenesis as well.

关键词： α-TCP/TTCP bone cement biocompatibility bioactivity

SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis

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Computers, Materials & Continua 2025年第1期82卷 1417-1437页

作者： Hongxing wang Xilai Ju hua Zhu huafeng Li State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Computer Science and Engineering Nanyang Technological UniversitySingapore639798Singapore

Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain ***,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis ***,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault ***,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative *** complexity results in high computational costs and limited industrial *** tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault ***,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration ***,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global ***,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and *** study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.

关键词： CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis

EFFECT OF Y2O3 ON THE PROPERTY OF NiO/Al2O3 CATALYST FOR PARTIAL OXIDATION OF METHANE

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Journal of Energy Chemistry 1994年第4期 453-458页

作者： GAO Xiang CHENG Ji-yuan FU Xi-yu wang hua-Ming YAO Ruo-BingChengdu Institute of Organic Chemistry, Academia Sinica Chengdu, Sichuan 610015

The effects of YOon the property of NiO/AlOcatalyst forcatalytic partial oxidation of methane were investigated in a continuous flowfixed bed reactor（20 mm i.d.,860 mm long）.The catalysts werecharacterized by XRD and pore *** comparison,similar studieswere carried out for the catalysts loaded with Zr or W *** results showthat different additives and impregnating methods could greatly affect thedispersion of component *** catalytic activity,the selectivity to CO andthe stability are improved because of the less facile interation between thesupport and nickel oxide,greater surface area and better dispersion of metalNi for NiO/AlOcatalyst modified by YO.

关键词： NiO EFFECT OF Y2O3 ON THE PROPERTY OF NiO/Al2O3 CATALYST FOR PARTIAL OXIDATION OF METHANE COI XRD Al

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： yu‑Ze wang yu‑Chang wang Ting‑Ting Liu Quan‑Liang Zhao Chen‑Sha Li Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Effects of grinding environment and lattice impurities on spodumene flotation

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Transactions of Nonferrous Metals Society of China 2019年第7期29卷 1527-1537页

作者： Guang-li ZHU yu-hua wang Xu-ming wang Jan D. MILLER Dong-fang LU Xia-yu ZHENG yue-hao ZHAO Hai-tao ZHENG School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China College of Mines and Earth Sciences University of UtahSalt Lake City 84112USA

The effect of grinding on the spodumene flotation was investigated. The flotation response of spodumene ground by different mills was different, due to the variation of metal ions on spodumene surfaces caused by grinding environments and/or impurities. The samples were subjected to acid pickling treatment to remove most of the metal ions from the surfaces, and then all samples showed the same poor flotation response, which confirmed the significance of surface metal ions. Metal ion impurities may come from both grinding environments and lattice substitutions in spodumene. Density functional theory (DFT) calculation revealed that Fe and Ca could exist as lattice substitutions on the spodumene surface while Mg substitution is unlikely to occur. Furthermore, Fe is considered to be active site for the absorption of sodium oleate on the spodumene surface. Morphology analysis showed differences in particle size and shape for samples ground by different mills, resulting in different amounts of exposed surfaces. The particle size, cleavage characteristics caused by grinding environments, and metal ion impurities originated from grinding and isomorphous substitutions, play significant roles in the chemisorption of collector on the spodumene surface.

关键词： grinding lattice substitution metal ion impurities density functional theory (DFT) calculation spodumene cleavage flotation