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Olive oil ameliorate allergic response in ovalbumin-induced food allergy mouse by promoting intestinal mucosal immunity
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作者 Yu Ma Ming liu +5 位作者 donghui li Jie li Zixin Guo Yunjun liu Shengnan Wan Yixiang liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期801-808,共8页
The numerous health benefits of olive oil are widely known,however,it also provides anti-allergic properties that have not yet been fully defined.In this study,the anti-allergic activity of olive oil was evaluated by ... The numerous health benefits of olive oil are widely known,however,it also provides anti-allergic properties that have not yet been fully defined.In this study,the anti-allergic activity of olive oil was evaluated by analyzing the clinical symptoms and immune-related factors in BALB/c mice that had ingested600 mg/(kg·day)olive oil for two weeks prior to the evaluation.An allergy model was subsequently constructed for analysis,the results of which showed that the olive oil reduced the scores of allergic symptoms in the mice,and up-regulated the hypothermia and the decline in the immune organ index.Moreover,fewer allergy-related cytokines and reduced intestinal inflammation was discovered in the olive oil-treated group.In addition,analysis of intestinal mucosal immune-related factors revealed that the olive oil promoted the expression of intestinal tight junction proteins(Claudin-1,Occludin,and ZO-1)and IL-22,and helped maintain the integrity of the intestinal epithelial physical barrier.Increased levels of mucin 2 andβ-defensin were also found in the intestinal mucus of the olive oil-treated mice.These findings suggest that the oral administration of olive oil effectively attenuated the ovalbumin-induced allergic immune response in the mice,and had a positive effect on intestinal epithelial mucosal immunity. 展开更多
关键词 Olive oil Ovalbumin-induced food allergy Anti-food allergy Intestinal mucosal immunization
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Enhanced activation of peroxymonosulfate by Fe/N co-doped ordered mesoporous carbon with dual active sites for efficient removal of m-cresol 被引量:1
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作者 donghui li Wenzhe Wu +6 位作者 Xue Ren Xixi Zhao Hongbing Song Meng Xiao Quanhong Zhu Hengjun Gai Tingting Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期130-144,共15页
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th... The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS. 展开更多
关键词 Degradation PEROXYMONOSULFATE Fe(II)/Fe(III)/FeN4 Ordered mesopores carbon Catalyst Radical
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Modelling the Roles of Cewebrity Trust and Platform Trust in Consumers’Propensity of Live-Streaming:An Extended TAM Method 被引量:8
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作者 donghui li Guozheng Zhang +4 位作者 Zeng Xu Yong Lan Yongdong Shi Zhiyao liang Haiwen Chen 《Computers, Materials & Continua》 SCIE EI 2018年第4期137-150,共14页
Live streaming is a booming industry in China,involving an increasing number of Internet users.Previous studies show that trust is a cornerstone to develop ecommerce.Trust in the streaming industry is different from t... Live streaming is a booming industry in China,involving an increasing number of Internet users.Previous studies show that trust is a cornerstone to develop ecommerce.Trust in the streaming industry is different from that of other e-commerce areas.There are two major dimensions of trust in the live streaming context:platform trust and cewebrity trust,which are both important for customers to adopt and reuse a specific live streaming service.We collected questionnaire data from 520 participates who have used live streaming services in China.We model the collected data and identified factors that can influence users’propensity by an extended technology acceptance model(TAM)method.According to our analysis,both cewebrity trust and platform trust will greatly influence users’intention to reuse a certain platform.Moreover,results also indicate that cewebrity trust is far more important than platform trust.These findings can lead to several management strategies to improve the adherence of users to streaming platforms. 展开更多
关键词 Live streaming extended TAM approach consumers’propensity cewebrity trust platform trust
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An overview of the geology and production of the Fuling shale gas field,Sichuan Basin,China 被引量:16
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作者 Haikuan Nie donghui li +4 位作者 Guangxiang liu Zhiyuan Lu Hu Wang Ruyue Wang Guangrong Zhang 《Energy Geoscience》 2020年第3期147-164,共18页
The Fuling shale gas field in China is the largest shale gas field as well as the largest of its type discovered in any Lower Paleozoic formation.In this study,the geology and production of the upper and lower gas lay... The Fuling shale gas field in China is the largest shale gas field as well as the largest of its type discovered in any Lower Paleozoic formation.In this study,the geology and production of the upper and lower gas layers in the Fuling shale gas field are evaluated in terms of structure,shale quality,fault,initial production,and estimated ultimate recovery(EUR).The shale in the lower gas layer of the Jiaoshiba anticline is a high-quality reservoir,where the space is dominated by organic pores in kerogen,and the gas content is high.The shale gas wells reveal relatively high initial production and EUR.However,the shale in the upper gas layer of the Jiaoshiba anticline has reservoir space mainly composed of clay mineral pores and organic pores within bitumen,and the gas content is low.In terms of structure,primary gas migration may occur in the upper gas layer,resulting in free gas accumulation in the structural high,where the development effects are generally better than those in the structural low.The lower gas layer in the Pingqiao anticline,is the main interval for shale gas accumulation and development due to the high-quality shale.Under the influence of faults,the efficiency of exploration wells emplaced on top of the anticline is much lower a compared with those in the flanks.The residual synclines close to the Sichuan Basin,including the Baima and Baitao anticlines,are characterized by more recent uplifts,larger area,greater distance from the deep and large faults,and early fracture closure.Therefore,we recommend that the shale gas exploration and development should be carried out preferentially in areas close to the center of the residual synclines,featuring relatively high-pressure coefficient and moderate burial depth. 展开更多
关键词 Geologic characteristics Production features Longmaxi formation Fuling shale gas field Sichuan basin
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High-efficient solar-driven hydrogen production by full-spectrum synergistic photo-thermo-catalytic methanol steam reforming with in-situ photoreduced Pt-CuO_(x) catalyst 被引量:3
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作者 donghui li Jie Sun +1 位作者 Rong Ma Jinjia Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期460-469,I0012,共11页
Synergy between the intrinsic photon and thermal effects from full-spectrum sunlight for H_(2) production is considered to be central to further improve solar-driven H_(2) production.To that end,the photo-thermocataly... Synergy between the intrinsic photon and thermal effects from full-spectrum sunlight for H_(2) production is considered to be central to further improve solar-driven H_(2) production.To that end,the photo-thermocatalyst that demonstrates both photoelectronic and photothermal conversion capabilities have drawn much attention recently.Here,we propose a novel synergistic full-spectrum photo-thermo-catalysis technique for high-efficient H_(2) production by solar-driven methanol steam reforming(MSR),along with the Pt-Cu Oxphoto-thermo-catalyst featuring Pt-Cu/Cu_(2)O/CuO heterojunctions by Pt-mediated in-situ photoreduction of Cu O.The results show that the H_(2) production performance rises superlinearly with increasing light intensity.The optimal H_(2) production rate of 1.6 mol g^(-1) h^(-1) with the corresponding solar-to-hydrogen conversion efficiency of 7%and the CO selectivity of 5%is achieved under 15×sun full-spectrum irradiance(1×sun=1 k W m^(-2))at 180°C,which is much more efficient than the previously-reported Cu-based thermo-catalysts for MSR normally operating at 250~350°C.These attractive performances result from the optimized reaction kinetics in terms of intensified intermediate adsorption and accelerated carrier transfer by long-wave photothermal effect,and reduced activation barrier by short-wave photoelectronic effect,due to the broadened full-spectrum absorbability of catalyst.This work has brought us into the innovative technology of full-spectrum synergistic photothermo-catalysis,which is envisioned to expand the application fields of high-efficient solar fuel production. 展开更多
关键词 Solar-driven Hydrogen production Photo-thermo-catalysis Copper oxide Methanol steam reforming Reaction kinetics optimization
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Longitudinal Measurement of Hemodynamic Changes within the Posterior Optic Nerve Head in Rodent Nonarteritic Anterior Ischemic Optic Neuropathy 被引量:2
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作者 Jin Ma Ting Chen +5 位作者 Yiwei Wang Chan Zhao donghui li Meng Wang linyang Gan Yong Zhong 《Chinese Medical Sciences Journal》 CAS CSCD 2018年第4期252-259,共8页
ObjectiveTo assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). MethodsrNAION was established with Rose Bengal a... ObjectiveTo assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). MethodsrNAION was established with Rose Bengal and argon green laser in Sprague-Dawley rats. Fundus photography and fundus fluorescein angiography (FFA) were performed to assess the dynamic changes of optic disc in morphology in 90 days and in blood perfusion in 3 hours after the induction of disease. Histological examinations were performed to evaluate the success of modeling. Thedynamic blood flow kinetics of posterior ONH in rNAION were measured by Laser Doppler Flowmetry (LDF) on the day 3, 7, 14, 21, and 40 after the disease induction. One-way ANOVA, Student'st-test and Bonferroni adjustment were used for multiple comparisons of kinetic measurements of blood flow. ResultsOptic disc edema and subsequent resolution associated with the development of optic disc pallor were observed in rNAION. FFA showed that the optic disc was hypofluorescence in the early phase and hyperfluorescence in the late phase. Histological studies suggested edema and loosened tissues of ONH, loss of retinal ganglion cells (RGCs), optic nerve substance and gliosis. Compared to the naive rats, the blood flow kinetics of posterior ONH in rNAION significant reduced at each time point after modeling (F=175.06,P<0.0001). The reductions were specifically remarkable in 14 days after the disease induction (AllP<0.01). Conclusions Continuous blood perfusion reduction was found in rNAION, with significant alteration in 14 days after disease induction. Our results provided important information for understanding the hemodynamic changes in rNAION. 展开更多
关键词 nonarteritic ANTERIOR ISCHEMIC OPTIC NEUROPATHY rat model POSTERIOR OPTIC nerve head blood flow in vivo
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Research on Data Fusion of Adaptive Weighted Multi-Source Sensor 被引量:3
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作者 donghui li Cong Shen +5 位作者 Xiaopeng Dai Xinghui Zhu Jian Luo Xueting li Haiwen Chen Zhiyao liang 《Computers, Materials & Continua》 SCIE EI 2019年第9期1217-1231,共15页
Data fusion can effectively process multi-sensor information to obtain more accurate and reliable results than a single sensor.The data of water quality in the environment comes from different sensors,thus the data mu... Data fusion can effectively process multi-sensor information to obtain more accurate and reliable results than a single sensor.The data of water quality in the environment comes from different sensors,thus the data must be fused.In our research,self-adaptive weighted data fusion method is used to respectively integrate the data from the PH value,temperature,oxygen dissolved and NH3 concentration of water quality environment.Based on the fusion,the Grubbs method is used to detect the abnormal data so as to provide data support for estimation,prediction and early warning of the water quality. 展开更多
关键词 Adaptive weighting multi-source sensor data fusion loss of data processing grubbs elimination
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An Opinion Spam Detection Method Based on Multi-Filters Convolutional Neural Network 被引量:2
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作者 Ye Wang Bixin liu +4 位作者 Hongjia Wu Shan Zhao Zhiping Cai donghui li Cheang Chak Fong 《Computers, Materials & Continua》 SCIE EI 2020年第10期355-367,共13页
With the continuous development of e-commerce,consumers show increasing interest in posting comments on consumption experience and quality of commodities.Meanwhile,people make purchasing decisions relying on other com... With the continuous development of e-commerce,consumers show increasing interest in posting comments on consumption experience and quality of commodities.Meanwhile,people make purchasing decisions relying on other comments much more than ever before.So the reliability of commodity comments has a significant impact on ensuring consumers’equity and building a fair internet-trade-environment.However,some unscrupulous online-sellers write fake praiseful reviews for themselves and malicious comments for their business counterparts to maximize their profits.Those improper ways of self-profiting have severely ruined the entire online shopping industry.Aiming to detect and prevent these deceptive comments effectively,we construct a model of Multi-Filters Convolutional Neural Network(MFCNN)for opinion spam detection.MFCNN is designed with a fixed-length sequence input and an improved activation function to avoid the gradient vanishing problem in spam opinion detection.Moreover,convolution filters with different widths are used in MFCNN to represent the sentences and documents.Our experimental results show that MFCNN outperforms current state-of-the-art methods on standard spam detection benchmarks. 展开更多
关键词 Opinion spam detection deceptive reviews deep learning convolutional neural network activation function
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Realizing compact three-dimensional charge transport networks of asymmetric electron acceptors for efficient organic solar cells 被引量:1
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作者 Jinlong Cai Yiwei Fu +6 位作者 Chuanhang Guo donghui li liang Wang Chen Chen Dan liu Wei li Tao Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第2期508-517,共10页
Asymmetry has been demonstrated an effective approach in recent years to tune the structural and energetic orders of nonfullerene electron acceptors(NFAs)to prepare efficient organic solar cells(OSCs).In this article,... Asymmetry has been demonstrated an effective approach in recent years to tune the structural and energetic orders of nonfullerene electron acceptors(NFAs)to prepare efficient organic solar cells(OSCs).In this article,five asymmetric NFAs,namely C9BTP-BO-Th Cl-2F,C9BTP-BO-Cl-2F,C9BTP-BO-2Cl-2F,C7BTP-BO-2Cl-2F and C5BTP-BO-2Cl-2F possessing varied asymmetric end-groups and alkyl chains are synthesized to tune the charge transport networks formed within these NFAs.We found that the enhanced planarity in the asymmetric NFA can facilitate closerπ-πstacking distance in either the A-to-A or A-toD type NFA dimers,whilst the larger dipole moment can promote the formation of three-dimensional(3D)charge transport networks among NFAs.Taking those advantages,C7BTP-BO-2Cl-2F exhibit a compact 3D honeycomb network with a high packing coefficient of 72.1%and molecular packing density of 0.48 g/cm^(3),contributing to a superior power conversion efficiency of 18.0%when employing PM6 as the donor,with an open-circuit voltage of 0.85 V,short-circuit current of26.7 m A cm^(-2)and fill factor of 79.3%.Our work provides guidelines in engineering the end group and side chains of asymmetric NFAs to achieve compact charge transport networks for high efficiency OSCs. 展开更多
关键词 organic solar cells asymmetric non-fullerene electron acceptor PLANARITY dipole moment charge transport networks
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Large-Scale KPI Anomaly Detection Based on Ensemble Learning and Clustering 被引量:1
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作者 Ji Qian Fang liu +2 位作者 donghui li Xin Jin Feng li 《Journal of Cyber Security》 2020年第4期157-166,共10页
Anomaly detection using KPI(Key Performance Indicator)is critical for Internet-based services to maintain high service availability.However,given the velocity,volume,and diversified nature of monitoring data,it is dif... Anomaly detection using KPI(Key Performance Indicator)is critical for Internet-based services to maintain high service availability.However,given the velocity,volume,and diversified nature of monitoring data,it is difficult to obtain enough labelled data to build an accurate anomaly detection model for using supervised machine leaning methods.In this paper,we propose an automatic and generic transfer learning strategy:Detecting anomalies on a new KPI by using pretrained model on existing selected labelled KPI.Our approach,called KADT(KPI Anomaly Detection based on Transfer Learning),integrates KPI clustering and model pretrained techniques.KPI clustering is used to obtain the similarity of different KPI data's distribution,and applied transfer knowledge from source dataset to the target dataset by model pretrained technique.In our evaluation using real-world KPIs from large Internet-based services,the clustering algorithm used to detect various KPI curve pattern achieve the best classification effect and accuracy More importantly,further evaluation on 30 KPIs shows that KADT can significantly reduce the time overhead of the model training with little loss of accuracy. 展开更多
关键词 Anomaly detection time series clustering transfer learning
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Heating induced aggregation in non-fullerene organic solar cells towards high performance
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作者 Baocai Du Renyong Geng +7 位作者 Wenliang Tan Yuchao Mao donghui li Xue Zhang Dan liu Weihua Tang Wenchao Huang Tao Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期131-137,共7页
Molecular ordering within the photoactive layer plays a crucial role in determining the device performance of organic solar cells(OSCs).However,the simultaneous molecular ordering processes of polymer donors and non-f... Molecular ordering within the photoactive layer plays a crucial role in determining the device performance of organic solar cells(OSCs).However,the simultaneous molecular ordering processes of polymer donors and non-fullerene acceptors(NFAs)during solution casting usually bring confinement effect,leading to insufficient structural order of photovoltaic components.Herein,the molecular packing of mINPOIC NFA is effectively formed through a heating induced aggregation strategy,with the aggregation of PBDB-T,which has a strong temperature dependence,is retarded by casting on a preheated substrate to reduce its interference toward m-INPOIC.A sequent thermal annealing treatment is then applied to promote the ordering of PBDB-T and achieve balanced aggregation of both donors and acceptors,resulting in the achievement of a maximum efficiency of 13.9% of PBDB-T:m-INPOIC binary OSCs.This work disentangles the interactions of donor polymer and NFA during the solution casting process and develops a rational strategy to enhance the molecular packing of NFAs to boost device performance. 展开更多
关键词 Organic solar cells Non-fullerene acceptor Heating induced aggregation
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Identifying extracerebellar characteristics in a large cohort of 319 Chinese patients with spinocerebellar ataxia type 3
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作者 donghui li Jinyang Yu +4 位作者 Chenhao Zhu Yichu Du Yin Ma Yi Dong Zhiying Wu 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第17期2131-2133,共3页
To the Editor:Spinocerebellar ataxia type 3(SCA3)is the predominant subtype,representing 48-73%of all SCAs in the Chinese population.[1]It primarily manifests as progressive ataxia,characterized by unsteady gait,dysar... To the Editor:Spinocerebellar ataxia type 3(SCA3)is the predominant subtype,representing 48-73%of all SCAs in the Chinese population.[1]It primarily manifests as progressive ataxia,characterized by unsteady gait,dysarthria,and limb clumsiness,due to cerebellar and interconnected gray matter damage.Notably,extracerebellar features such as extrapyramidal and oculomotor abnormalities,and spasticity,often remain underrecognized.This complexity can lead to misdiagnosis,underscoring the necessity for a more comprehensive understanding of both cerebellar and extracerebellar symptoms. 展开更多
关键词 representing CEREBELLAR predominant
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LIMITED MEMORY BFGS METHOD FOR NONLINEAR MONOTONE EQUATIONS 被引量:3
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作者 Weijun Zhou donghui li 《Journal of Computational Mathematics》 SCIE EI CSCD 2007年第1期89-96,共8页
In this paper, we propose an algorithm for solving nonlinear monotone equations by combining the limited memory BFGS method (L-BFGS) with a projection method. We show that the method is globally convergent if the eq... In this paper, we propose an algorithm for solving nonlinear monotone equations by combining the limited memory BFGS method (L-BFGS) with a projection method. We show that the method is globally convergent if the equation involves a Lipschitz continuous monotone function. We also present some preliminary numerical results. 展开更多
关键词 Limited memory BFGS method Monotone function Projection method.
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Excellent magnetic softness-magnetization synergy and suppressed defect activation in soft magnetic amorphous alloys by magnetic field annealing 被引量:1
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作者 Qiang Luo donghui li +5 位作者 Mingjuan Cai Siyi Di Zhengguo Zhang Qiaoshi Zeng Qianqian Wang Baolong Shen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第21期72-82,共11页
Fe-based amorphous alloys with high saturation magnetic flux density(B_(s))are increasingly attractive from both scientific and technological points of view,however,they usually suffer from the trade-off between magne... Fe-based amorphous alloys with high saturation magnetic flux density(B_(s))are increasingly attractive from both scientific and technological points of view,however,they usually suffer from the trade-off between magnetization and softness.In this work,we explore the soft magnetic properties(SMPs),magnetic and atomic structures,and defect activation during creep deformation of as-quenched and annealed Fe_(82.65-x)Co_(x)Si_(2)B_(14)Cu_(1.35)(x=0-20)amorphous alloys(AAs).Improved magnetic softness-magnetization synergy has been realized in all these alloys by field annealing.Particularly,superb SMPs with superhigh B_(s) of 1.86 T,low coercivity of 1.2 A/m and high effective permeability of 16300 are obtained in the Fe_(66.65)Co_(16)Si_(2)B_(14)Cu_(1.35) AA.The locally regularized arrangement of domains,homogenized structure with less structural/magnetic defects and suppressed crystal-like ordering by field annealing contribute synergistically to the superb SMPs.Besides,the relaxation time spectra obtained from creep deformation indicate less liquid-like and solid-like defects activated in the field-annealed AA,which is correlated with the structural homogenization and superb SMPs.This work provides new and comprehensive insight into the interplay among external field,heterogeneous structure,SMPs and defect activation of Fe-based AAs,and offers a promising pathway for softening amorphous alloys with high Bs. 展开更多
关键词 Fe-based amorphous alloy Soft magnetic performance Magnetic field annealing Heterogeneous structure Defect activation
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Aeroelastic Properties and Nonlinear Vibration Control of a Simply-Supported Lattice Sandwich Beam Embedded with Nitinol-Steel Wire Ropes 被引量:1
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作者 Yewei Zhang Xichao Chen +1 位作者 donghui li Jian Zang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2022年第5期755-764,共10页
As a novel vibration absorber,Nitinol-steel wire rope(NiTi-ST)has rarely been studied on vibration suppression for lattice sandwich beams in supersonic airflow.In this paper,NiTi-ST with nonlinear stiffness and hyster... As a novel vibration absorber,Nitinol-steel wire rope(NiTi-ST)has rarely been studied on vibration suppression for lattice sandwich beams in supersonic airflow.In this paper,NiTi-ST with nonlinear stiffness and hysteretic damping is embedded in a lattice sandwich beam to control the beam's vibration.The nonlinear restoring and hysteretic damping force of NiTi-ST are treated as polynomials.The dynamic equation is established based on Hamilton's principle.The amplitude responses of the beam with different NiTi-ST configurations are calculated.The vibration-suppression effects and energy dissipation of lattice sandwich beam with different NiTi-ST configurations under different air velocities are also compared.The frequency-domain and time-domain methods are used to analyze the structural aeroelastic properties.Simulation results show that the use of NiTi-ST can significantly suppress excessive vibration of a lattice sandwich beam in supersonic airflow. 展开更多
关键词 Lattice sandwich beam Nonlinear vibration control Nitinol-steel wire rope Supersonic airflow
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Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts:preparation and catalytic activity
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作者 Qing YE donghui li +3 位作者 Jun ZHAO Jiansheng ZHAO Tianfang KANG Shuiyuan CHENG 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第4期497-504,共8页
Au-supported 13X-type zeolite(Au/13X)was synthesized using a common deposition-precipitation(DP)method with a solution of sodium carbonate as a precipitate agent.Further testing was conducted to test for catalytic oxi... Au-supported 13X-type zeolite(Au/13X)was synthesized using a common deposition-precipitation(DP)method with a solution of sodium carbonate as a precipitate agent.Further testing was conducted to test for catalytic oxidation of CO.A study was conducted on the effects of different preparation conditions(i.e.,chloroauric acid concentration,solution temperature,pH of solution,and calcinations temperature)on Au/13X for CO oxidation.In respect to the catalytic activity,the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction,TEM and XPS.The activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid concentration.From XRD results,a higher chloroauric acid concentration induced larger gold nanoparticles,which resulted in lower catalytic activity.Results revealed that higher temperatures induced higher Au loading,homogeneous deposit,and smaller gold clusters on the support of 13X,resulting in higher CO activity.Furthermore,a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or 9.This may be a result of an effective exchange between Au(OH)_(2)Cl_(2)^(-)and Au(OH)_(3)Cl^(-)on specific surface sites of zeolite under the pH’s 5 and 6.The sample calcined at 300℃showed the highest activity,which may be due to the sample’s calcined at 200℃inability to decompose completely to metallic gold while the sample calcined at 400℃had larger particles of gold deposited on the support.It can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5×10^(-3)mol·L^(-1)gold solution pH of 6,solution temperature of around 90℃,and a calcination temperature of 300℃provides optimum catalytic activity for CO oxidation. 展开更多
关键词 13X-type zeolite CO oxidation gold solution pH calcination temperature
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CONVERGENCE OF THE CYCLIC REDUCTION ALGORITHM FOR A CLASS OF WEAKLY OVERDAMPED QUADRATICS
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作者 Bo Yu donghui li Ning Dong 《Journal of Computational Mathematics》 SCIE CSCD 2012年第2期139-156,共18页
In this paper, we establish a convergence result of the cyclic reduction (CR) algorithm for a class of weakly overdamped quadratic matrix polynomials without assumption that the partial multiplicities of the nth lar... In this paper, we establish a convergence result of the cyclic reduction (CR) algorithm for a class of weakly overdamped quadratic matrix polynomials without assumption that the partial multiplicities of the nth largest eigenvalue are all equal to 2. Our result can be regarded as a complement of that by Guo, Higham and Tisseur [SIAM J. Matrix Anal. Appl., 30 (2009), pp. 1593-1613]. The numerical example indicates that the convergence behavior of the CR algorithm is largely dictated by our theory.Mathematics subject classification: 15A24, 15A48. 展开更多
关键词 Weakly overdamped quadratics Cyclic reduction Doubling algorithm.
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Satellite remote sensing of atmospheric particulate matter mass concentration:Advances,challenges,and perspectives
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作者 Ying Zhang Zhengqiang li +15 位作者 Kaixu Bai Yuanyuan Wei Yisong Xie Yuanxun Zhang Yang Ou Jason Cohen Yuhuan Zhang Zongren Peng Xingying Zhang Cheng Chen Jin Hong Hua Xu Jie Guang Yang Lv Kaitao li donghui li 《Fundamental Research》 CAS 2021年第3期240-258,共19页
Mapping the mass concentration of near-surface atmospheric particulate matter(PM)using satellite observations has become a popular research niche,leading to the development of a variety of instruments,algorithms,and d... Mapping the mass concentration of near-surface atmospheric particulate matter(PM)using satellite observations has become a popular research niche,leading to the development of a variety of instruments,algorithms,and datasets over the past two decades.In this study,we conducted a holistic review of the major advances and challenges in quantifying PM,with a specific focus on instruments,algorithms,datasets,and modeling methods that have been developed over the past 20 years.The aim of this study is to provide a general guide for future satellite-based PM concentration mapping practices and to better support air quality monitoring and management of environmental health.Specifically,we review the evolution of satellite platforms,sensors,inversion algorithms,and datasets that can be used for monitoring aerosol properties.We then compare various practical methods and techniques that have been used to estimate PM mass concentrations and group them into four primary categories:(1)univariate regression,(2)chemical transport models(CTM),(3)multivariate regression,and(4)empirical physical approaches.Considering the main challenges encountered in PM mapping practices,for example,data gaps and discontinuity,a hybrid method is proposed with the aim of generating PM concentration maps that are both spatially continuous and have high precision. 展开更多
关键词 Satellite remote sensing Particulate matter Aerosol optical depth Air quality monitoring Environmental modeling
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深冷处理对低碳高合金马氏体轴承钢力学性能及组织的影响 被引量:17
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作者 李东辉 李志敏 +3 位作者 肖茂果 李绍宏 赵昆渝 杨卯生 《材料研究学报》 EI CAS CSCD 北大核心 2019年第8期561-571,共11页
利用洛氏硬度计、X射线衍射仪、扫描电子显微镜及透射电子显微镜等研究了低碳高合金马氏体轴承钢深冷处理后的硬度变化及组织演化。结果表明:深冷处理促使部分残留奥氏体转变为马氏体,导致深冷处理后实验钢的硬度较淬火态硬度有所升高... 利用洛氏硬度计、X射线衍射仪、扫描电子显微镜及透射电子显微镜等研究了低碳高合金马氏体轴承钢深冷处理后的硬度变化及组织演化。结果表明:深冷处理促使部分残留奥氏体转变为马氏体,导致深冷处理后实验钢的硬度较淬火态硬度有所升高。经深冷处理后实验钢在0~100 h回火过程中的硬度均比未深冷处理实验钢的硬度高。深冷处理促使钢中碳原子偏聚并在回火过程中以碳化物的形式析出,与未经深冷处理的实验钢相比,经深冷处理的实验钢回火后马氏体基体中的含碳量更低,表明实验钢经深冷处理后在回火过程中析出更多的碳化物。透射电镜分析表明,实验钢在回火过程中析出的大量弥散分布的纳米级M2C和M6C型碳化物是实验钢长时间回火后保持高硬度的主要原因。 展开更多
关键词 金属材料 高合金钢 深冷处理 碳化物 残留奥氏体
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Optimum design and experiment of composite leaf spring landing gear for electric aircraft 被引量:3
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作者 donghui li Zhenwei FAN +2 位作者 Yewei ZHANG Jian ZANG Fengtian YANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第10期2649-2659,共11页
The composite leaf spring landing gear of an electric aircraft is optimized.With the strength and workability as constraints and the minimum structural weight as an objective,the two-stage optimization of the leaf spr... The composite leaf spring landing gear of an electric aircraft is optimized.With the strength and workability as constraints and the minimum structural weight as an objective,the two-stage optimization of the leaf spring landing gear with glass fiber unidirectional prepreg is carried out using a genetic algorithm,namely,the optimization of continuous thickness of layup,and the optimization of the layup sequence and discrete thickness.In the optimization process,the ground loads are calculated according to the structural stiffness of each chromosome,thus the stiffness constraints are relaxed,and the optimization results are compared with those using stiffness constraints.The static experiment verification reveals that the numerical simulation and experimental results are consistent,that is,the optimized leaf spring meets the strength requirements.The results show that the leaf spring landing gear based on two-stage optimization method achieves the objective of weight reduction. 展开更多
关键词 Composite materials Genetic algorithm Laminate optimization Landing gear Static experiment
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