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105篇 您的检索式:作者名="Yang Qingfeng"
    题名 作者 年代 出处 被引量
1Passive-source ocean bottom seismograph(OBS) array experiment in South China Sea and data quality analyses显示文摘Long-term passive source ocean bottom seismograph(OBS) observatory is challenging due to various technical difficulties. In order to gain experience in this field, and to reveal the lithospheric structure beneath the extinct ridge in the central South China Sea(SCS), we carried out a passive source OBS array experiment, which includes 18 OBSs, in the deep portion of SCS. Here we present the instrumentation, the OBS deployment and recovery of this experiment, and more importantly, the data quality evaluated by a number of approaches. Through processing and inspecting waveforms from global, regional and local earthquakes, we find that most of recovered OBSs have good data quality with discernible main phases. The ambient noise analyses of OBS recordings show that their noise is higher than the global average, and the horizontal component is noisier than the vertical, indicating current impacts on horizontal components are more severe. In the period range of 5–10 s, there is a noise notch for the SCS OBSs, and noise levels of horizontal components are comparable to the vertical. This feature, which is not seen at OBS stations in open ocean, suggests the distant sources for double frequency microseism in this marginal sea are not significant. In addition, we successfully determined the orientations for 7 OBSs by investigating their Rayleigh wave polarizations; and we demonstrated the dispersion feature of Rayleigh waves through the frequency-time analysis. Finally, we summarized lessons learned from this experiment regarding the passive source OBS investigations in SCS.Chenguang Liu Qingfeng Hua Yanliang Pei Ting Yang Shaohong Xia Mei Xue Ba Manh Le Da Huo Fang Liu Haibo Huang 2014Chinese Science Bulletin2014,59,33:11
2Palaeoecological and palaeoenvironmental significance of someimportant spores and micro-algae in Quaternary deposits显示文摘Spores of ferns and allied plants, and micro-algae frequently occur in abundance in Quaternary deposits, but their palaeoenvironmental significance is seldom evaluated. This paper presents morphological descriptions of spores of Selaginella sinensis (Desv.) Spring, 1843 (Selaginellaceae) and Ceratopteris cf. thalictroides (L.) Brongniart, 1821 (Parkeriaceae) and the algae Pediastrum boryanum (Turpin) Meneghini, 1840, P. simplex Meyen, 1829, P. integrum N geli, 1849 (all Hydrodictyaceae), Spiniferites Mantell, 1850, emend. Sarjeant, 1970 (Spiniferitaceae) and Concentricystes Rossignal, 1962, emend. Jiabo, 1978 (systematic position unclear), and discusses their occurrence in mostly Quaternary sedimentary successions. All are closely associated with aquatic habitats. Extant Selaginella sinensis often colonizes fairly wet hillsides and gaps between rocks, and shady sides of ravines and slopes; it is also found within thickets of trees and shrubs (boscages) and in forests with calcareous soils. Ceratopteris thalictroides, Pediastrum and Concentricystes inhabit freshwater lakes and both natural and artificial wetlands, such as paddy fields and ditches. Spiniferites is a salt-water genus and usually associated with the marine realm. Fossil and subfossil representatives of all of these taxa can be useful proxies of biodiversity and, therefore, also important for determining environmental conditions during the Quaternary period.TANG LingYu MAO LiMi Lü XinMiao MA QingFeng ZHOU ZhongZe YANG ChunLei KONG ZhaoChen BATTEN David J 2013Chinese Science Bulletin2013,58,25:9
3Carbon-supported Fe/Co-N electrocatalysts synthesized through heat treatment of Fe/Co-doped polypyrrole-polyaniline composites for oxygen reduction reaction显示文摘In this paper,we synthesized cathode catalysts(PANI-PPYR,Fe/PANI-PPYR,Co/PANI-PPYR and Fe-Co/PANI-PPYR)with high performance oxygen reduction by using a simple heat treatment process.These catalysts were fabricated by directly calcining the Fe and/or Co doped polyaniline(PANI)-polypyrrole(PPYR)composites.Their electrocatalytic activity for ORR both in acidic and in alkaline media was investigated by voltammetric techniques.Among the prepared catalysts,Co/PANI-PPYR presents the most positive ORR onset potential of 0.62 V(vs.SCE)in 0.5 mol/L H2SO4 solution or?0.09 V(vs.SCE)in 1 mol/L NaOH solution.In addition,the Co/PANI-PPYR catalyst shows the largest limiting-diffusion current density for ORR,which is 4.3 mA/cm2@0.2 V(vs.SCE)in acidic and 2.3 mA/cm2@?0.3 V(vs.SCE)in alkaline media.In acidic media,a four-electron reaction of ORR on the Co/PANI-PPYR and Fe/PANI-PPYR catalysts is more dominant than a two-electron reaction.In alkaline media,however,a four-electron and a two-electron mechanisms are co-present for the ORR on all the prepared catalysts.Co/PANI-PPYR catalyst also presents good electrocatalytic activity stability for ORR both in acidic and in alkaline media.YI QingFeng ZHANG YuHui LIU XiaoPing YANG YaHui 2014Science China Chemistry2014,57,5:8
4Deformation mechanism and microstructures on polycrystalline aluminum induced by high-current pulsed electron beam显示文摘In this paper, we present an experimental investigation of deformation twinning in polycrystalline aluminum exposed to high-current pulsed electron beam (HCPEB) irradiation. The residual tensile stress with about 10 2 MPa was introduced in the irradiated surface layer. The feature characteristic irradiated with various numbers of pulses was investigated. The formation of a large number of twin bands on the surface irradiated with multiple pulses was determined. The experimental observations indicated that the deformation twinning was indeed triggered during HCPEB irradiation. It is suggested that high value of stress and strain rate induced by rapid heating and cooling due to HCPEB irradiation may cause the shifting of whole atomic planes simultaneously. Additionally, some slipping systems may be suppressed due to the geometric confinement by thinned size of surface layer, which can promote the initiation of deformation twinning.CAI Jie JI Le YANG ShengZhi WANG XiaoTong LI Yan HOU XiuLi GUAN QingFeng 2013Chinese Science Bulletin2013,58,20:7
5A naturally occurring CD8^+CD122^+ T-cell subset as a memory-like Treg family显示文摘尽管有 CD4 + CD25 + 规章的 T 房间(Tregs ) 在过去的十年期间,在他们的临床的翻译以后的进步仍然保持停滞。增长证据建议那自然地发生的 CD8 + CD122 + T 房间也是有能力的 Tregs 禁止 T 房间回答并且象 alloimmunity 一样压制 autoimmunity。事实上,他们是像记忆的 Tregs 类似于一个中央记忆 T 房间(T 厘米 ) 显型。位于他们的抑制下面的机制仍然不好被理解,尽管他们可以包括 IL-10 生产。我们最近证明了那个规划 death-1 (PD-1 ) 表达式区分在之间规章并且存储器 CD8 + CD122 + T 房间和那 CD8 + CD122 + Tregs 经历更快的 homeostatic 增长并且比常规 CD4 + CD25 + Tregs。这些调查结果可以为在诊所加速有效 Treg 治疗打开调查的一根新线。在这评论,我们在 CD8 + CD122 + Treg 在诊所研究并且讨论他们的显型,在 autoimmunity 和 alloimmunity 的镇压角色,功能的要求,行动的机制和潜在的应用。Shanshan Li Qingfeng Xie Yuqun Zeng Chuan Zou Xusheng Liu Shouhai Wu Haixia Deng Yang Xu Xian C Li Zhenhua Dai 2014Cellular & Molecular Immunology2014,11,4:6
6Molecular characteristics of the omp A gene of serotype B Chlamydia trachomatis in Qinghai Tibetan primary school students显示文摘To study the molecular characteristics of Chlamydia trachomatis, the major outer membrane protein gene(omp A) of C. trachomatis from primary school students with trachoma residing in the Qinghai Tibetan area was sequenced and compared with the same serotype in Gen Bank. In Jianshetang Primary School and Galeng Central Primary School in the Galeng Tibetan Township of Qinghai Haidong Sala Autonomous County, scraped samples were collected from the upper tarsal conjunctiva and lower conjunctival sac of both eyes of 45 students with trachoma, stored at 4°C, and transported to Beijing Tongren Hospital by air within 24 h. The samples were screened for C. trachomatis by real-time PCR. The omp A gene from the C. trachomatis-positive samples was amplified by nested PCR. The serotype was confirmed by National Center for Biotechnology Information(NCBI) BLAST search and homology analysis. The entire omp A gene sequence was compared with the corresponding gene sequences of serotype B strains available in Gen Bank. Of the 45 students aged 6–13 years with trachoma, 26 C. trachomatis-positive students were identified by the initial real-time PCR screening(average age,(9.09±1.63) years; sex ratio, 1.0), accounting for 57.78%(26/45). The cycle threshold values for real-time PCR were 16.79–37.77. Half(13/26) of C. trachomatis-positive students had a bacterial copy number of >105. The compliance rate of the omp A gene sequences with the C. trachomatis serotype B strains in Gen Bank was up to 99%. Two novel genetic mutations were found when the omp A gene was compared with those of the 11 serotype B strains in Gen Bank. The two non-synonymous mutations were located at(i) position 271 in the second constant domain, an adenine(A) to guanine(G) substitution(ACT?GCT), changing the amino acid at position 91 from threonine to alanine(Thr?Ala) in all 26 strains; and(ii) position 887 in the fourth variable domain, a cytosine(C) to thymine(T) substitution(GCA?GTA), changing the amino acid at residue 296 from alanine to valine(Ala?Val) in four of the 26 strains. Six mutations were identified relative to ATCC VR-573. The strains could be divided into two gene clusters according to the mutation at nucleotide position 887: CQZ-1(China Qinghai Tibetan-1) and CQZ-2(China Qinghai Tibetan-2). We thus detected two novel serotype B mutant strains of C. trachomatis among study subjects with trachoma.Xue Li Shaoya Zhang Qingfeng Liang Mei Wang Ailian Hu Xiuyuan Li Benshan Yang Mingxin Zhang Ningli Wang Xinxin Lu 2016Science China(Life Sciences)2016,59,6:6
7A phosphatidic acid-binding lncRNA SNHG9 facilitates LATS1 liquid–liquid phase separation to promote oncogenic YAP signaling显示文摘Long noncoding RNAs(lncRNAs)are emerging as a new class of important regulators of signal transduction in tissue homeostasis and cancer development.Liquid–liquid phase separation(LLPS)occurs in a wide range of biological processes,while its role in signal transduction remains largely undeciphered.In this study,we uncovered a lipid-associated lncRNA,small nucleolar RNA host gene 9(SNHG9)as a tumor-promoting lncRNA driving liquid droplet formation of Large Tumor Suppressor Kinase 1(LATS1)and inhibiting the Hippo pathway.Mechanistically,SNHG9 and its associated phosphatidic acids(PA)interact with the C-terminal domain of LATS1,promoting LATS1 phase separation and inhibiting LATS1-mediated YAP phosphorylation.Loss of SNHG9 suppresses xenograft breast tumor growth.Clinically,expression of SNHG9 positively correlates with YAP activity and breast cancer progression.Taken together,our results uncover a novel regulatory role of a tumor-promoting lncRNA(i.e.,SNHG9)in signal transduction and cancer development by facilitating the LLPS of a signaling kinase(i.e.,LATS1).Rui-Hua Li Tian Tian Qi-Wei Ge Xin-Yu He Cheng-Yu Shi Jun-Hong Li Zhen Zhang Fang-Zhou Liu Ling-Jie Sang Zuo-Zhen Yang Ya-Zhuo Liu Yan Xiong Qingfeng Yan Xu Li Huai-Qiang Ju Jian Liu Liang-Jing Wang Jian-Zhong Shao Wenqi Wang Tianhua Zhou Aifu Lin 2021Cell Research2021,31,10:6
8Does an extended mediastinal lymphadenectomy improve outcome after R0 resection in lung cancer?显示文摘Objective: This retrospective study was conducted to investigate the impact of more extended mediastinal lymphadenectomy on the outcome of lung cancer patients treated with R0 resection.Methods: During the investigation period, 325 lung cancer cases were enlisted and 278 cases entered the analysis. The patients were divided into Control group(n=116) and Research group(n=162) according to the different extents of mediastinal lymph node clearance at different time periods. Three major parameters were retrospectively assessed to compare the quality of surgical care: extent of lymph node clearance, resection volume, and postoperative recovery process and common complications. Comparison of the outcome between two groups was carried out.Results: Research group showed a significant quality improvement of lymphadenectomy, such as more mediastinal node stations investigated(more than 3 N2 stations investigated: Research group, 90.7% vs. Control group, 55.2%; P=0.001) and more nodes collection(total nodes 26.1±10.0 vs. 19.1±8.3, P=0.000; N2 nodes 15.5±7.2 vs. 9.8±5.6, P=0.000). However, overall survival(OS) and disease-free survival(DFS) were not significantly different either between two groups(5-year OS: Control group, 56.4±4.6% vs. Research group, 62.6±4.3%; P=0.271) or between subgroups from stage I to IIIa. TNM stage and histology were significant factors associated with OS and DFS in multivariate analysis; extent of mediastinal lymphadenectomy was not associated with OS or DFS.Conclusions: More radical mediastinal lymphadenectomy may not lead to an improved oncological outcome for lung cancer treated with R0 resection.Nan Wu Shi Yan Chao Lv Shaolei Li Yuan Feng Yuzhao Wang Jia Wang Qingfeng Zheng Yue Yang 2014Chinese Journal of Cancer Research2014,26,2:5
9Sonication-assisted dispersion of carbon nanotubes in aqueous solutions of the anionic surfactant SDBS:The role of sonication energy显示文摘Sonication is a powerful technique to promote the dispersion of carbon nanotubes(CNTs) and enhance their solubility;this is necessary for CNT applications,especially in the biochemical and biomedical fields.In this study,batch experiments were conducted to evaluate the role of sonication energy on the dispersion of CNTs in the presence of a widely used anionic surfactant,sodium dodecylbenzene sulfonate(SDBS).It was observed that the concentration of dispersed CNTs in the SDBS solution depended on the sonication energy,but not the sonication time or output power of the sonicator alone.The amount of dispersed CNTs was positively correlated with the concentrations of SDBS and CNTs,and the length of the CNTs.The promotion of oxygen-containing functional groups on the dispersed CNTs was observed at relatively low sonication energies.The optimal energy,i.e.the minimum energy supplied by sonication to achieve a saturated suspension of dispersed CNTs in the SDBS solution,was CNT diameter-dependent,because of the larger vdW forces between tubes of smaller diameter.An exponential decay curve was constructed for the optimal energy values as a function of the outer CNT diameter,to assist in determining the energy needed to disperse CNTs.YANG Kun YI ZiLi JING QingFeng YUE RenLiang JIANG Wei LIN DaoHui 2013Chinese Science Bulletin2013,58,18:5
10Multimetallic AuPd@Pd@Pt core-interlayer-shell icosahedral electrocatalysts for highly efficient oxygen reduction reaction显示文摘Incorporating Pt with core metals into Pt-based core-shell catalysts is regarded as a promising strategy to substantially enhance the catalytic properties towards oxygen reduction reaction(ORR) in fuel cells due to the synergetic effect between distinct metals. In this wok, ultrathin Pt skins with two atomic layers were epitaxially coated on as-prepared icosahedral Au_50Pd_50, Au_60Pd_40 and Au_66Pd_34 nanocrystal seeds,which are constructed with alloyed cores and Pd shells with different thickness. Through electron microscopic characterizations, Pd interlayers with tunable thickness of 3, 6, and 12 atomic layers can be found in the Au_66Pd_34@Pt, Au_60 Pd_40@Pt and Au_50Pd_50@Pt icosahedra, respectively. These icosahedral Au Pd@Pd@Pt nanocrystals show substantially enhanced activities and durabilities in electrocatalytic measurements towards ORR compared to Au_75Pd_25@Pt icosahedra without Pd interlayer and commercial Pt/C catalysts. Specifically, Au_60Pd_40@Pt icosahedra with 6 atomically thick Pd interlayer display the best electrocatalytic performances, whose mass activities before and after durability tests of 50,000 cycles are11.6 and 30.2 times, respectively, as high as that of the commercial Pt/C.Qingfeng Xu Wenlong Chen Yucong Yan Zhemin Wu Yi Jiang Junjie Li Ting Bian Hui Zhang Jianbo Wu Deren Yang 2018Science Bulletin2018,63,8:5
11Atomistic Surface Passivation of CH_(3)NH_(3)PbI_(3) Perovskite Single Crystals for Highly Sensitive Coplanar-Structure X-Ray Detectors显示文摘Organic-inorganic halide perovskites(OIHPs)are recognized as the promising next-generation X-ray detection materials.However,the device performance is largely limited by the ion migration issue of OIHPs.Here,we reported a simple atomistic surface passivation strategy with methylammonium iodide(MAI)to remarkably increase the ion migration activation energy of CH_(3)NH_(3)PbI_(3)single crystals.The amount of MAI deposited on the crystal surface is finely regulated by a self-assemble process to effectively suppress the metallic lead defects,while not introducing extra mobile ions,which results in significantly improved dark current stability of the coplanar-structure devices under a large electric field of 100Vmm^(-1).The X-ray detectors hence exhibit a record-high sensitivity above 700,000μC Gy^(-1)_(air) cm^(-2)under continuum X-ray irradiation with energy up to 50 keV,which enables an ultralow X-ray detection limit down to 1.5 nGy_(air)s^(-1).Our findings will allow for the dramatically reduced X-ray exposure of human bodies in medical imaging applications.Yilong Song Liqi Li Weihui Bi Mingwei Hao Yifei Kang Anran Wang Zisheng Wang Hanming Li Xiaohui Li Yanjun Fang Deren Yang Qingfeng Dong 2020Research2020,,1:5
12Interaction mechanism of the interface between a deep buried sand and a paleo-weathered rock mass using a high normal stress direct shear apparatus显示文摘In order to evaluate the feasibility of safe mining close to the contact zone under reduced security coal pillar conditions at a coal mine in eastern China, the interaction mechanism of the interface between deep buried sand and a paleo-weathered rock mass was investigated in the laboratory by direct shear testing. A DRS-1 high pressure soil shear testing machine and orthogonal design method were used in the direct shear tests. Variance and range methods were applied to analyze the sensitivity of each factor that has an influence on the mechanical characters of the interface. The test results show that the normal pressure is the main influencing factor for mechanical characteristics of the interface, while the lithological characters and roughness are minor factors; the shear stress against shear displacement curve for the interface shows an overall hyperbola relationship, no obvious peak stress and dilatancy was observed.When the normal pressure is 6 MPa, the shear strengths of interfaces with different roughness are basically the same, and when the normal pressure is more than 8 MPa, the larger the roughness of the interface, the larger will be the shear strength; the shear strength has a better linear relationship with the normal pressure, which can be described by a linear Mohr–Coulomb criterion.Bai Hanying Li Wenping Ding Qingfeng Wang Qiqing Yang Dongdong 2015International Journal of Mining Science and Technology2015,25,4:4
13Fargeted elimination of mutant mitochondria DNA in MELAS-iPSCs by mitoTALENs显示文摘Yi Yang Han Wu Xiangjin Kang Yanhui Liang Ting Lan Tianjie Li Tao Tan Jiangyun Peng Quanjun Zhang Geng An Yali Liu Qian Yu Zhenglai Ma Ying Lian Boon Seng Soh Qingfeng Chen Ping Liu Yaoyong Chen Xiaofang Sun Rong Li Xiumei Zhen Yang Yu Xiaoping Li Yong Fan 2018Protein & Cell2018,9,3:4
14Characteristics of pathogenic microorganisms found in 99 cases of conjunctivitis from the Qinghai Tibetan area显示文摘Dear Editor,Morbidity associated with conjunctivitis is higher in developing countries,particularly among children,because of the poorer standards of living(Azari and Barney,2013;Yetman and Coody,1997).Presently,little is known regarding the microorganisms that cause conjunctivitis in the remote area of Chinese Tibet.In particular,it is difficult to monitor and control the occurrence of conjunctivitis in children from this area.Conjunctivitis has two forms:acute and chronic.Benshan Yang Xiuyuan Li Qingfeng Liang Shaoya Zhang Shijing Deng 2016Science China(Life Sciences)2016,59,6:4
15Roles of intracellular fibroblast growth factors in neural development and functions显示文摘Fibroblast growth factors (FGFs) can be classified as secretory (FGF1-10 and FGF15-23) or intracellular non-secretory forms (FGF11-14). Secretory forms of FGF and their receptors are best known for their regulatory roles in cell growth, differentiation and morphogenesis in the early stages of neural development. However, the functions of intracellular FGFs remain to be explored. FGF12 and FGF14 are found to interact with voltage-gated sodium channels, and regulate the channel activity in neurons. FGF13 is expressed in primary sensory neurons, and is colocalized with sodium channels at the nodes of Ranvier along the myelinated afferent fibers. FGF13 is also expressed in cerebral cortical neurons during the late developmental stage. A recent study showed that FGF13 is a microtubule-stabilizing protein required for regulating the neuronal development in the cerebral cortex. Thus, non-secretory forms of FGF appear to have important roles in the brain, and it would be interesting to further investigate the functions of intracellular FGFs in the nervous system and in neural diseases.ZHANG Xu BAO Lan YANG Liu WU QingFeng LI Shuai 2012Science China(Life Sciences)2012,55,12:4
16Effect of chronic corticosterone-induced depression on circadian rhythms and age-related phenotypes in mice显示文摘Disrupted circadian rhythms are a recognized effect of depression,and our previous article demonstrated an association between depression and premature aging,but the underlying mechanisms are not well understood.In the present study,we used a mouse model of chronic corticosterone (CORT)-treated depression to elucidate a mechanism by which depression may be associated with the circadian clock and mediate age-related phenotypes.Mice received a daily injection of 20 mg/kg CORT for 21 consecutive days,and the depression-like behaviors of mice were identified by the sucrose intake test,tail suspension test and open field test.Our findings indicated that CORT injection may be correlatedwith the circadian clock by impairing circadian rhythms or shifting the phase values of clock genes.We also showed that CORT-treated mice exhibited a significant gradual reduction in body weight gain with increased oxidative stress, including reduced activity of antioxidant-related enzymes,reduced glutathione:glutathione disulfide ratio and cytochrome (Cyt)-C level,and elevated reactive oxygen species content.Moreover, chronic CORT injection affected inflammatory responses,the production of mitochondrial ATP and telomere shortening,which may be associated with the Sirtuin 3 (SIRT3)signaling pathway. Additionally,chronic CORT injection disrupted the circadian rhythms of some indexes of aging phenotypes and altered the phase values of these indexes.Our findings suggest that psychologically stressful conditions such as depression are linked to changes in circadian rhythms and agerelated phenotypes.Lingyan iVla Qichen Shen Song Yang Xiaoxian Xie Qingfeng Xiao Chuanan Yu Lisha Cao Zhengwei Fu 2018Acta Biochimica et Biophysica Sinica2018,50,12:4
17Obacunone activates the Nrf2-dependent antioxidant responses显示文摘Xu, Shengmei Chen, Weimin Xie, Qingfeng Xu, Yang 2016Protein & Cell2016,7,9:4
18Superior performance and high service stability for Ge Te-based thermoelectric compounds显示文摘GeTe-based compounds have been intensively studied recently due to their superior thermoelectric performance,but their real applications are still limited so far due to the drastic volume variation that occurs during the rhombohedral–cubic phase transition,which may break the material or the material/electrode interface during service.Here,superior performance and high service stability for GeTe-based thermoelectric compounds are achieved by co-doping Mg and Sb into GeTe.The linear coefficient of thermal expansion before phase transition is greatly improved to match that after phase transition,yielding smooth volume variation around the phase transition temperature.Likewise,co-doping(Mg,Sb)in GeTe successfully tunes the carrier concentration to the optimal range and effectively suppresses the lattice thermal conductivity.A peak z T of 1.84 at 800 K and an average z T of 1.2 in 300–800 K have been achieved in Ge0.85Mg0.05Sb0.1Te.Finally,a Ni/Ti/Ge0.85Mg0.05Sb0.1Te thermoelectric uni-leg is fabricated and tested,showing quite good service stability even after 450 thermal cycles between 473 K and 800 K.This study will accelerate the application of GeTe-based compounds for power generation in the mid-temperature range.Tong Xing Qingfeng Song Pengfei Qiu Qihao Zhang Xugui Xia Jincheng Liao Ruiheng Liu Hui Huang Jiong Yang Shengqiang Bai Dudi Ren Xun Shi Lidong Chen 2019National Science Review2019,6,5:4
19Ordered mesoporous NiFe_2O_4 with ultrathin framework for low-ppb toluene sensing显示文摘Highly sensitive and selective detection against specific target gases,especially at low-ppb(part per billion)level,remain a great number of challenges in gas sensor applications.In this paper,we first present an ordered mesoporous NiFe_2O_4 for highly sensitive and selective detection against low-ppb toluene.A series of mesoporous NiFe_2O_4 materials were synthesized by templating from mesoporous silica KIT-6 and its framework thickness was reduced from 8.5 to 5 nm by varying the pore size of KIT-6 from 9.4 to 5.6 nm,accompanied with the increase of the specific surface area from 134 to 216 m^2g^(-1).The ordered mesoporous NiFe_2O_4 with both ultrathin framework of 5 nm and large specific surface area of up to 216 m^2g^(-1)exhibits a highest response(R_(gas)/R_(air)-1=77.3)toward 1,000 ppb toluene at 230℃ and is nearly 7.3 and 76.7 times higher than those for the NiFe_2O_4 replica with thick framework and its bulk counterpart respectively,which also possesses a quite low limit of detection(<2 ppb),and good selectivity.Xiaoyong Lai Kun Cao Guoxin Shen Ping Xue Dan Wang Fang Hu Jianli Zhang Qingfeng Yang Xiaozhong Wang 2018Science Bulletin2018,63,3:3
20Growth of ultra-dense MoS_(2) nanosheets on carbon fibers to improve the mechanical and tribological properties of polyimide composites显示文摘To enhance the interface bonding of polyimide(PI)/carbon fiber(CF)composites,CFs were functionalized by introducing a polydopamine(PDA)transition layer,whose active groups provide absorption sites for the growth of molybdenum disulfide(MoS_(2))nanosheets and improve the bonding strength with PI.Uniform and dense MoS_(2) nanosheets with thicknesses of 30–40 nm on the surface of the PDA@CF were obtained via a subsequent hydrothermal method.As a result,the interface between the CF and the PI matrix becomes more compact with the help of the PDA transition layer and MoS_(2) nanosheets.This is beneficial in forming PI/CF–MoS_(2) composites with better thermal stability,higher tensile strength,and enhanced tribological properties.The lubricating and reinforcing effects of the hybrid CF–MoS_(2) in the PI composite are discussed in detail.The tensile strength of the PI/CF–MoS_(2) composite increases by 43%,and the friction coefficient and the wear rate reduce by 57%and 77%,respectively,compared to those of the pure PI.These values are higher than those of the PI/CF composites without MoS_(2) nanosheets.These results indicate that the CF–MoS_(2) hybrid material can be used as an additive to improve the mechanical and tribological properties of polymers.Jin YANG Qingfeng XIAO Zhe LIN Yong LI Xiaohua JIA Haojie SONG 2021Friction2021,9,5:3
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