|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Catalytic oxidation of benzene over Ce-Mn oxides synthesized by flame spray pyrolysis显示文摘Flame spray pyrolysis(FSP) was utilized to synthesize Ce-Mn oxides in one step for catalytic oxidation of benzene.Cerium acetate and manganese acetate were used as precursors.The materials synthesized were characterized using X-ray diffraction(XRD),N_2 adsorption,X-ray photoelectron spectroscopy(XPS).transmission electron microscopy(TEM),Raman spectroscopy,and Fh-temperature programmed reduction(H_2-TPR) and their benzene catalytic oxidation behavior was evaluated.Mn ions were evidenced in multiple chemical states.Crystalline Ce-Mn oxides consist of particles with size <40 nm and specific surface areas(SSA) of 20-50m^2/g.Raman spectrums and H_2-TPR results indicated the interaction between cerium and manganese oxides.Flame-made 12.5%-Ce-Mn oxide exhibited excellent catalytic activity at relatively low temperatures(T95 about 260 C) compared to other Ce-Mn oxides with different ceriumto-manganese ratios.Redox mechanism and strong interaction conform to structure analysis that Ce-Mn strong interaction formed during the high temperature flame process and the results were used to explain catalytic oxidation of benzene. | Gang Liu Renliang Yue Yi Jia Yong Ni Jie Yang Haidi Liu Zhen Wang Xiaofeng Wu Yunfa Chen | 2013 | Particuology2013,11,4: | 17 |
| 2 | Effects of cerium incorporation on the catalytic oxidation of benzene over flame-made perovskite La_(1-x)Ce_xMnO_3 catalysts显示文摘Perovskite-type La_(1-x)Ce_xMnO_3(x = 0-10%) catalysts were prepared by flame spray pyrolysis and their activities during the catalytic oxidation of benzene were examined over the temperature range of100-450℃.The structural properties and reducibility of these materials were also characterized by X-ray diffraction(XRD),N_2 adsorption/desorption,H_2 temperature-programmed reduction(H_2-TPR) and X-ray photoelectron spectroscopy(XPS).The incorporation of Ce was found to improve the benzene oxidation activity,and the perovskite in which x was 0.1 exhibited the highest activity.Phase composition and surface elemental analyses indicated that non-stoichiometric compounds were present.The incorporation of Ce had a negligible effect on the specific surface area of the perovskites and hence this factor has little impact on the catalytic activity.Introduction of Ce4^(4+) resulted in modification of the chemical states of both B-site ions and oxygen species and facilitated the reducibility of the perovskite.The surface Mn^(4+)/Mn^(3+)ratio was increased as a result of Ce^(4+) substitution,while a decrease in the surface-adsorbed O/lattice O(O_(ads)/O_(latt)) ratio was observed.The relationship between the surface elemental ratios and catalytic activity was established to allow a better understanding of the process by which benzene is oxidized over perovskites. | Gang Liu Jiaqi Li Kun Yang Wenxiang Tang Haidi Liu Jun Yang Renliang Yue Yunfa Chen | 2015 | Particuology2015,13,2: | 6 |
| 3 | Preparation and electrochemical performance of carbon-coated LiFePO4/LiMnPO4-positive material for a Li-ion battery显示文摘 | Qiangqiang Tan Bo Yan Yuxing Xu Yunfa Chen Jun Yang | 2017 | Particuology2017,15,1: | 5 |
| 4 | Discrimination of Motor Imagery Patterns by Electroencephalogram Phase Synchronization Combined With Frequency Band Energy显示文摘Central nerve signal evoked by thoughts can be directly used to control a robot or prosthetic devices without the involvement of the peripheral nerve and muscles.This is a new strategy of human-computer interaction.A method of electroencephalogram(EEG) phase synchronization combined with band energy was proposed to construct a feature vector for pattern recognition of brain-computer interaction based on EEG induced by motor imagery in this paper,rhythm and beta rhythm were first extracted from EEG by band pass filter and then the frequency band energy was calculated by the sliding time window;the instantaneous phase values were obtained using Hilbert transform and then the phase synchronization feature was calculated by the phase locking value(PLV) and the best time interval for extracting the phase synchronization feature was searched by the distribution of the PLV value in the time domain.Finally,discrimination of motor imagery patterns was performed by the support vector machine(SVM).The results showed that the phase synchronization feature more effective in4s-7s and the correct classification rate was 91.4%.Compared with the results achieved by a single EEG feature related to motor imagery,the correct classification rate was improved by 3.5 and4.3 percentage points by combining phase synchronization with band energy.These indicate that the proposed method is effective and it is expected that the study provides a way to improve the performance of the online real-time brain-computer interaction control system based on EEG related to motor imagery. | Chuanwei Liu Yunfa Fu Jun Yang Xin Xiong Huiwen Sun Zhengtao Yu | 2017 | IEEE/CAA Journal of Automatica Sinica2017,4,3: | 3 |
| 5 | Design and fabrication of 1-D semiconductor nanomaterials for high-performance photovoltaics显示文摘To date, the cost-effective utilization of solar energy by photovoltaics for large-scale deployment remains challenging. Further cost minimization and efficiency maximization, through reduction of material consumption, simplification of device fabrication as well as optimization of device structure and geometry, are required. The usage of 1D nanomaterials is attractive due to the outstanding light coupling effect, the ease of fabrication, and integration with one-dimensional(1-D) semiconductor materials. The light absorption efficiency can be enhanced significantly, and the corresponding light-toelectricity conversion efficiency can be as high as their bulk counterparts. Also, the amount of active materials used can be reduced. This review summarizes the recent development of 1-D nanomaterials for photovoltaic applications, including the anti-reflection, the light absorption,the minority diffusion, and the semiconductor junction properties. With solid progress and prospect shown in the past 10 years, 1-D semiconductor nanomaterials are attractive and promising for the realization of high-efficiency and low-cost solar cells. | Ning Han Zaixing Yang Lifan Shen Hao Lin Ying Wang Edwin Y.B.Pun Yunfa Chen Johnny C.Ho | 2016 | Science Bulletin2016,61,5: | 3 |
| 6 | Preparation and characterization of a novel hybrid chelating material for effective adsorption of Cu(Ⅱ)and Pb(Ⅱ)显示文摘The discharge of heavy metal ions such as Cu^2+and Pb^2+poses a severe threat to public health and the environment owing to their extreme toxicity and bioaccumulation through food chains Herein, we report a novel organic–inorganic hybrid adsorbent, Al(OH)_3-poly(acrylamide dimethyldiallylammonium chloride)-graft-dithiocarbamate(APD), for rapid and effectiv removal of Cu^2+and Pb^2+. In this adsorbent, the 'star-like' structure of Al(OH)3 poly(acrylamide-dimethyldiallylammonium chloride) served as the support of dithiocarbamat(DTC) functional groups for easy access of heavy metal ions and assisted development of larg and compact floccules. The synthesized adsorbent was characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), and thermogravimetric analysis(TGA). APD was demonstrated to hav rapid adsorption kinetics with an initial rate of 267.379 and 2569.373 mg/(g·min) as well a superior adsorption capacities of 317.777 and 586.699 mg/g for Cu^2+and Pb^2+respectively. Th adsorption process was spontaneous and endothermic, involving intraparticle diffusion and chemical interaction between heavy metal ions and the functional groups of APD. To assess it versatility and wide applicability, APD was also used in turbid heavy metal wastewater, and performed well in removing suspended particles and heavy metal ions simultaneously through flocculation and chelation. The rapid, convenient and effective adsorption of Cu^2+and Pb^2+give APD great potential for heavy metal decontamination in industrial applications. | Ya Liu Peng Qian Yang Yu Bo Yu Yongliang Wang Shufeng Ye Yunfa Chen | 2018 | Journal of Environmental Sciences2018,30,5: | 2 |
| 7 | Superparamagnetic Iron Oxide is Suitable to Label Tendon Stem Cells and Track Them In Vivo with MR Imaging显示文摘 | Yunfa Yang Jianying Zhang Yongxian Qian Shiwu Dong He Huang Fernando E. Boada Freddie H. Fu James H-C. Wang | 2013 | Annals of Biomedical Engineering2013,,10: | 1 |
| 8 | Characterization of MHC class Ⅱ A genes in Hainan Eld's deer(Cervus eldi hainanus)显示文摘The major histocompatibility complex(MHC) genes play pivotal roles in the immune system of vertebrates against antigens.They are also significant indicators of genetic structure,and are vital to species-level population viability analyses and disease risk assessments.In this study,two DRA and two DQA sequences were isolated from Hainan Eld's deer(Cervus eldi hainanus) using rapid amplification of cDNA ends(RACE) and single-strand conformation polymorphism-heteroduplex(SSCP-HD) analysis.Nucleotide sequence analysis revealed large differences between the two DQA sequences,especially in their exon 2 regions,but only minimal differences between the variants of the DRA gene.Comparison of the predicted amino acid sequences of the Ceel-MHC class Ⅱ A variants with those from six other species revealed that these molecules share high homology among ruminants.A phylogenetic tree of four class Ⅱ A sequences from Hainan Eld's deer and the other species placed the newly identified DQA and DRA genes on two distinct branches(100%-supportively),and further divided the two DQA sequences into 98%-supportive DQA1 and 99%-supportive DQA2 clusters,respectively.Therefore,this study identified monomorphic Ceel-DQA1 and Ceel-DQA2 genes,and one dimorphic Ceel-DRA gene from Hainan Eld's deer. | LIU HongYi YANG HaiQiong GE YunFa | 2013 | Chinese Science Bulletin2013,58,17: | 1 |
| 9 | Epoxy/α-alumina nanocomposite with high electrical insulation performance显示文摘An experimental study was conducted to improve the electrical insulation of epoxy resin. The effects of boehmite, γ-alumina and α-alumina nanoparticles on the volume resistivity, dielectric strength and glass transition temperature of epoxy nanocomposites were investigated. The results showed that α-alumina nanoparticles displayed obvious advantages in enhancing electrical insulation performance of epoxy nanocomposites, compared to boehmite and γ-alumina nanoparticles. The direct current volume resistivity and breakdown strength of epoxy nanocomposite with 2.0 wt% α-alumina nanoparticles was improved to 2.2 × 10^(18)Ω cm and76.1 kV mm^(-1) respectively. And these improved values of electrical insulation properties are much higher than these of epoxy nanocomposites reported in previous studies. The main reason of these improvements may be that the epoxy/α-alumina interaction zone was enhanced by crosslink. | Yun Chen Donghai Zhang Xiaofeng Wu Haosheng Wang Chong Zhang Wei Yang Yunfa Chen | 2017 | Progress in Natural Science:Materials International2017,27,5: | 1 |
| 10 | Cenozoic Ephedraceae adaptation to global cooling in northwestern China显示文摘Ephedraceae has been applied largely as a drought indicator to reconstruct Cenozoic paleoenvironment and paleoclimate. However, temperature indication of Ephedraceae has been largely ignored. Here, we provide a record of Ephedraceae percentage spanning from the Early Eocene to Middle Miocene (52-17 Myr B.P.) in the Xining Basin, northeastern Tibetan Plateau. This record is comparable to a compiled Cenozoic Ephedraceae record from five other basins in northwestern China. Both records show Ephedraceae percentages were high during the Early Eocene, and decreased gradually from the Middle Eocene to Late Oligocene, then maintained a stable level since the Late Oligocene. By comparing these two Ephedraceae records with the marine oxygen isotope record, we discuss the variation of Ephedraceae percentage in Middle Cenozoic in response to global temperature change. Ephedraceae percentage was high in the Early Paleogene, associated with subtropical or tropical vegetation types in a global greenhouse climate, and decreased in Early Oligocene, associated with global cooling, suggesting that Ephedraceae is warm-tolerant during the Paleogene. The low Ephedraceae percentages in the Late Oligocene and Miocene were uncoupled with global warming, which may imply that Ephedraceae began to adapt to a eurythermic climate in the inland desert environment of western China. Such adaptation may be a response to the high topography of the Tibetan Plateau. | YunFa Miao XiaoLi Yan YaJun Shao Bao Yang | 2011 | Research in Cold and Arid Regions2011,3,5: | 1 |
| 11 | Relationships between modern pollen and vegetation and climate on the eastern Tibetan Plateau显示文摘The Tibetan Plateau ecosystem is fragile and sensitive to climate change. Understanding the relationships between modern pollen and the vegetation and climate of the region is critical for the evaluation of ecological processes.Here, we explore modern pollen assemblages of typical land-cover types at a large spatial scale by analyzing 36surface samples from the southeastern Tibetan Plateau, supplemented by typical desert, desert-steppe, and steppe meadow transition data selected from the Chinese Surface Pollen Database, giving a total of 75 samples. We used redundancy analysis(RDA) to explore the responses of vegetation in the assemblages to regional climate. Our results show that pollen assemblages generally reflect the vegetation composition: assemblages from alpine meadow samples are dominated by Cyperaceae, Asteraceae, Rosaceae, and Polygonaceae;alpine shrublands mainly comprise Fabaceae, Rosaceae, Ericaceae, and Quercus(Q. spinosa);and coniferous forest surface samples mainly comprise Picea, Abies, Pinus, and Betulaceae. Our RDA shows that mean annual precipitation(MAP) is the main meteorological factor affecting the pollen assemblage and vegetation type;MAP positively correlates with percentages of Cyperaceae, Poaceae, Rosaceae, and Asteraceae, and negatively correlates with percentages of Chenopodiaceae, Ephedraceae, Nitraria, and Tamaricaceae. The ratio of Artemisia to Chenopodiaceae is a useful indicator to distinguish temperate desert from other land-cover types on the Tibetan Plateau, while the ratio of Cyperaceae + Asteraceae to Artemisia + Chenopodiaceae can be used to distinguish arid desert from other landcover types, and may provide a useful altitude index for the eastern Tibetan Plateau. | Lin Lin YunFa Miao YongTao Zhao Dong Yang Gen Wang | 2023 | Research in Cold and Arid Regions2023,15,2: | 0 |
| 12 | XIAP expression and its predictive significance of prognosis in stage IIB osteosarcomas显示文摘Objective: To evaluate X-linked inhibitor of apoptosis protein (XIAP) expression in biopsy specimens from the patients with stage IIB osteosarcomas before chemotherapy to study XIAP expression and its predictive significance of prognosis in stage IIB osteosarcomas. Methods: The expression of XIAP was retrospectively detected by SP immunohistochemistry in 31 cases biopsy specimens from stage IIB osteosarcomas before chemotherapy, and the relationship between XIAP expression and clinicopathologic features of the patients with stage IIB osteosarcomas was analyzed. Results: The osteo-sarcoma specimens showed strong cell nucleus immunoreaction of XIAP while normal bone specimens showed weak. High XIAP positive expression independently predicted the patient’s poor outcome and had no relationship with clinicopathologic variables such as age, gender, location, tumor size, rate of tumor necrosis to preoperative chemotherapy, local recurrence (P > 0.05). Significant correlations were found between high XIAP expression and metastasis (P = 0.022), and also between high XIAP expression and final survival (P = 0.011). Conclusion: XIAP plays an important role in the development of stage IIB osteosarcomas and XIAP expression of biopsy specimens before chemotherapy can be seen as a promising prognostic marker in early predicting the outcome of patients suffering from stage IIB osteosarcomas. | Yunfa Yang Hong DU Pin Huang Jianwei Wang Guangming Zhang Zhonghe Xu | 2008 | The Chinese-German Journal of Clinical Oncology2008,7,7: | 0 |
| 13 | East Asian monsoon intensification promoted weathering of the magnesium-rich southern China upper crust and its global significance显示文摘The Oligocene-Miocene boundary Asian climatic reorganization linked to the northward migration of the East Asian monsoon into subtropical China is a potentially important but poorly constrained atmospheric CO_(2) consumption process.Here,we performed a first-order estimate of the CO_(2) consumption induced by silicate chemical weathering and organic carbon burial in subtropical China related to this climatic reorganization.Our results show that an increase in long-term CO_(2 )consumption by silicate weathering varies from 0.06×10^(12)to 0.87×10^(12)mol yr^(-1)depending on erosion flux reconstructions,with an~50%contribution of Mg-silicate weathering since the late Oligocene.The organic carbon burial flux is approximately 25%of the contemporary CO_(2) consumption by silicate weathering.The results highlight the significant role of weathering of the Mg-rich upper continental crust in East China,which would contribute to the rapid decline in atmospheric CO_(2) during the late Oligocene and the Neogene rise in the seawater Mg content.If this climatic reorganization was mainly induced by the Tibetan Plateau uplift,our study suggests that the growth of the Himalayan-Tibetan Plateau can lead to indirect modification of the global carbon and magnesium cycles by changing the regional hydrological cycle in areas of East Asia that are tectonically less active. | Yibo YANG Albert GALY Xiaomin FANG Christian FRANCE-LANORD Shiming WAN Rongsheng YANG Jian ZHANG Ran ZHANG Song YANG Yunfa MIAO Yudong LIU Chengcheng YE | 2021 | Science China Earth Sciences2021,64,7: | 0 |
| 14 | Talcum-doped composite separator with superior wettability and heatproof properties for high-rate lithium metal batteries显示文摘Separator is supposed to own outstanding thermal stability,superior wettability and electrolyte uptake,which is essential for developing high-rate and safe lithium metal batteries(LMBs).However,commercial polyolefin separators possess poor wettability and limited electrolyte uptake.For addressing this issue,we put forward a composite separator to implement above functions by doping layered-silicate(talcum)into polyvinylidene fluoride(PVDF).With significant improvement of electrolyte absorption benefiting from the strong adsorption energy values(-1.64-1.70 eV)between talcum and the electrolyte in lithium metal batteries,PVDF/Talcum(PVDF/TM)composite separator owns a small contact angle and superior electrolyte uptake.PVDF/TM composite separator with 10 wt%talcum(T-10)owns a tiny contact angle of 8°,while those of polypropylene(PP)and PVDF are 48°and 20°with commercial electrolyte.Moreover,the addition of thermotolerant talcum endows the T-10 composite separator with great thermostability,whose thermal shrinkage is only 5.39%at 150°C for 0.5 h.The cell with LiFeO4cathode and the T-10 composite separator reaches 91.7 m Ah/g in discharge capacity at 4.8 m A/cm^(2)(10 C),far superior to that with pure PVDF separator(56.3 m Ah/g)and PP(51.4 m Ah/g). | Mengqiu Yang Yuanpeng Ji Yunfa Dong Botao Yuan Liwei Dong Yuanpeng Liu Sue Hao Chunhui Yang Xiaoqiang Wu Qingquan Kong Jiecai Han Weidong He | 2023 | Chinese Chemical Letters2023,34,1: | 0 |
| 15 | Scalable fabrication of graphene-assembled multifunctional electrode with efficient electrochemical detection of dopamine and glucose显示文摘Conventional glassy carbon electrodes(GCE)cannot meet the requirements of future electrodes for wider use due to low conductivity,high cost,non-portability,lack of flexibility.Therefore,cost-effective and wearable electrode enabling rapid and versatile molecule detection is becoming important,especially with the ever-increasing demand for health monitoring and point-ofcare diagnosis.Graphene is considered as an ideal electrode due to its excellent physicochemical properties.Here,we prepare graphene film with ultra-high conductivity and customize the 3-electrode system via a facile and highly controllable laser engraving approach.Benefiting from the ultra-high conductivity(5.65×10^(5)S·m^(−1)),the 3-electrode system can be used as multifunctional electrode for direct detection of dopamine(DA)and enzyme-based detection of glucose without further metal deposition.The dynamic ranges from 1–200μM to 0.5–8.0 mM were observed for DA and glucose,respectively,with a limit of detection(LOD)of 0.6μM and 0.41 mM.Overall,the excellent target detection capability caused by the ultra-high conductivity and ease modification of graphene films,together with their superb mechanical properties and ease of mass-produced,provides clear potential not only for replacing GCE for various electrochemical studies but also for the development of portable and highperformance electrochemical wearable medical devices. | Xiaodong Ji Xin Zhao Zixin Zhang Yunfa Si Wei Qian Huaqiang Fu Zibo Chen Zhe Wang Huihui Jin Zhugen Yang Daping He | 2023 | Nano Research2023,16,5: | 0 |