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Active control of multiscale features in wall-bounded turbulence

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Acta Mechanica Sinica 2020年第1期36卷 12-21页

作者： xiaotong cui Nan Jiang Xiaobo Zheng Zhanqi Tang Department of Mechanics Tianjin UniversityTianjin300354China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin300354China School of Naval Architec.ure Ocean&civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

This study experimentally investigates the impact of a single piezoelectric(PZT)ac.uator on a turbulent boundary layer from a statistical *** working conditions of the ac.uator inc.ude a range of frequencies and *** streamwise velocity signals in the turbulent boundary layer flow are measured downstream of the ac.uator using a hot-wire *** mean velocity profiles and other basic parameters are *** results obtained by discrete wavelet decomposition indicate that the PZT vibration primarily influences the near-wall *** turbulent intensities at different scales suggest that the ac.uator redistributes the near-wall turbulent *** skewness and flatness distributions show that the ac.uator effectively alters the sweep events and reduces intermittency at smaller ***,under the impact of the PZT ac.uator,the symmetry of vibration scales’velocity signals is promoted and the struc.ural composition appears in an orderly *** distribution function results indicate that perturbation c.uses the fluc.uations in vibration scales and smaller scales with high intensity and low *** on the flatness factor,the bursting process is also *** vibrations reduce the relative intensities of the burst events,indicating that the streamwise vortices in the buffer layer experience direct interference due to the PZT control.

关键词： Turbulent boundary layer Piezoelectric ac.uator Drag reduction Discrete wavelet decomposition Bursting process

Provenance of the Late Permian Xuanwei Formation in the upper Yangtze Block: constraints from the Sedimentary Record and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1673-1686页

作者： ZHANG Yingli JIA xiaotong WANG Zongqi MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Engineering Seismology Institute of Zhejiang Province Hangzhou 310013China

Xuanwei Formation is composed of mudstone,siltstone,and sandstone,with local ***,its provenance and tectonic setting have been scarcely *** this paper,we use sedimentology,electron probe microanalysis(EPMA),and detrital zircon dating to investigate its source area and depositional tectonic *** facies assemblages indicate that it formed in alluvial fan and fluvial river sedimentary *** strata thicknesses and facies distribution indicate that the sediment supply was from the *** results of EPMA show that chromian spinels within the sediments are characterized by high cr#and varying Mg#.Discrimination plots suggest that these spinels were sourced from large igneous province(LIP)magmatic *** laser ablation inductively c.upled plasma mass spectrometry(LA-IcP-MS)u–Pb chronology of detrital zircons suggests that the sediments were derived from intermediate–acid igneous rocks dating back to 251–260?*** c.uld,therefore,conc.ude that the provenance of the Xuanwei Formation is from Emeishan basalt and synchronous felsic igneous rocks,which is consistent with the composition of the detrital *** detrital zircon dates also suggest that felsic magmatism oc.urred during the Late Permian,not after the eruption of the Emeishan *** on the sedimentary successions and provenance analysis,the tectonic setting for Xuanwei Formation deposition was a volcanic rifted margin.

关键词： Xuanwei Formation provenance analysis chromian spinel detrital zircon geochronology volcanic rifted margin

Effect of pre-calcination for modified caO-based sorbents on multiple carbonation/calcination cycles

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chinese Journal of chemical Engineering 2017年第10期25卷 1412-1421页

作者： xiaotong Liu Xiaoxun Ma Liu He Shisen Xu School of chemical Engineering Northwest University Xi'an 710069 China chemical Engineering Research center of the Ministry of Education for Advanced use Technology of Shanbei Energy Xi'an 710069 China Shaanxi Research center of Engineering Technology for clean coal conversion Xi'an 710069 China International Scientific and Technological cooperation Base for clean utilization of Hydrocarbon Resources Xi'an 710069 China china Huaneng Group clean Energy Technology Research Institute Beijing 100098 China

In the present work,the effect of pre-calcination on carbonation conversion and cyclic stability of modi fied caObased sorbent was investigated by thermogravimetric analyzer(TGA).The modi fied caO-based sorbents with caAc_2 as precursor were respectively doped with different elements(Mg,Al,ce,Zr and La).The speci fic surface area,pore volume and pore size distribution were tested by N_2 isothermal adsorption *** phase compositions of sorbents were characterized by X-ray diffraction(XRD).The results showed that the cyclic stabilities of the sorbents were improved by *** pre-calcination was conducted at 900°c for 5 h in air by the muf fle *** pre-calcination,the cyclic stabilities of sorbents c.uld be as high as 96% after 22 cycles,such as caO-Al,caO-ce and *** contact with air,the carbonation conversions of spent sorbents with pre-calcination suddenly increased by about one-sixth due to the change of channel struc.ure by *** the cyclic stability of sorbent and the durability of reactivation were related to the struc.ural stability of sample,especially the stability of mesopores between 2 nm and 5.5 *** present work also provided an easy and low-cost method for reactivating the spent caO-based sorbents.

关键词： ca O-based sorbent cyclic stability Pre-calcination Reactivation

Generalized uncertainty Inequalities on Fisher Information Associated with LcT

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Journal of Beijing Institute of Technology 2021年第3期30卷 217-227页

作者： Guanlei Xu Xiaogang Xu xiaotong Wang School of computer and Information Engineering Zhejiang Gongshang UniversityHangzhou 310018China

uncertainty principle plays an important role in multiple fields such as physics,mathem-atics,signal processing,*** linear canonical transform(LcT)has been used widely in optics and information processing and so *** this paper,a few novel uncertainty inequalities on Fisher information associated with linear canonical transform are *** newly deduced uncer-tainty relations not only introduce new physical interpretation in signal processing,but also build the relations between the uncertainty lower bounds and the LcT transform parameters a,b,c and d for the first time,which give us the new ideas for the analysis and potential *** addi-tion,these new uncertainty inequalities have sharper and tighter bounds which are the generalized versions of the traditional ***,some numeric examples are given to demon-strate the efficiency of these newly deduced uncertainty inequalities.

关键词： linear canonical transform(LcT) Fisher information uncertainty principle

Fe/N co-doped nano-TiO_(2)wrapped mesoporous carbon spheres for synergetically enhanced adsorption and photocatalysis

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Journal of Materials Science & Technology 2023年第4期135卷 54-64页

作者： xiaotong Feng Lifen Gu Naiyu Wang Qiaosheng Pu Guangli Liu Lanzhou Petrochemical Research center Petrochemical Research InstitutePetrochinaLanzhou 730060China State Key Laboratory of Applied Organic chemistry Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical engineeringLanzhou UniversityLanzhou 730000China

carbon-based adsorption and TiO_(2)-based photocatalysis are both safe and low-cost ways of pollutant *** c-TiO_(2)architec.ures can effectively improve removal ***,most of those carbon frames only acted as supporting substrates,exhibiting rather limited synergistic action from TiO_(2)and ***,Fe/N co-doped nano-TiO_(2)wrapped on mesoporous carbon spheres with a core-shell struc.ure was *** Fe,N co-doped carbon sphere with a hierarchical struc.ure im-proved the synergy of adsorption and transfer during the photocatalytic *** extra dopant,the Fe and N partly exposed on the surface realized the in-situ migrating into the TiO_(2)shell to en-hance the interface effect,which significantly promoted the photocatalytic efficiency of the ***,the photocatalytic efficiency of the composite was investigated through two typical pollu-tants under visible-light *** degradation efficiencies for rhodamine B and paraxylene were 96.2%in 60 min and 94.1%in 20 min,respectively,with the apparent rate constant of 0.045 min^(-1)and 0.049 min^(-1),8.3 and 11.4 times of that for bare TiO_(2).The composite is likely advantageous for treating diverse environmental pollutants.

关键词： Adsorption-photocatalysis Porous carbon Nano-TiO_(2) core-shell struc.ure co-doping

Genome-wide identification and in silico gene expression analysis of the related to ABI3/VP1(RAV)transcription factor family in barley(Hordeum vulgare L.)

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BIOcELL 2021年第6期45卷 1673-1685页

作者： cÜNEYT uÇARLI Department of Molecular Biology and Genetics Istanbul UniversityIstanbul34134Turkey

RAV(Related to ABI3/VP1)transcription factors are unique members of the AP2-ERF superfamily with AP2 and B3 domains and play important roles in the regulation of seed germination,plant growth,and stress *** the study,7 RAV genes,named HvRAVs,were identified in barley based on the available genome *** five of the seven HvRAVs were located on chromosome 3,HvRAV5 and HvRAV7 were located on chromosome 1 and 4,*** of the predicted HvRAVs were intron-less,except HvRAV2,which had one *** proteins have shown basic,instable,and hydrophilic *** AP2 domain specific RAYD and WLG motifs were detected in all HvRAV ***,B3 repression domain,R/KLFGV,is also found in the c-terminal of *** were found to have stress-related cis-acting elements,inc.uding MYB,MYc,and ***2 was predicted to have no GARE motifs,TATcccA or TAAcAA(G/A),and *** drought conditions,the expression level of HvRAVs did not significantly change in a drought-sensitive barley genotype,whereas HvRAV5 and HvRAV7 were dramatically down-regulated in a drought-tolerant *** of HvRAV5 was also inhibited by ***7 was strongly induced by plant pathogen *** HvRAV6 was induced by exogenous gibberellin application and during the germination ***,HvRAV6 transcript was detected higher than other HvRAVs in all stress and control conditions as well as during *** silico analyses have shown that HvRAVs play a role in response to different abiotic and biotic stresses as well as in plant ***,the extensive biological roles of HvRAV genes in plant development and in response to abiotic and biotic stresses need further investigation.

关键词： Barley RAV AP2 domain B3 domain AP2/ERF family cis-acting elements

Whole-genome RNAi screen identifies methylation-related genes influencing lipid metabolism in caenorhabditis elegans

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Journal of Genetics and Genomics 2018年第5期45卷 259-272页

作者： xiaotong Zhu Yangli Liu Hong Zhang Pingsheng Liu National Laboratory of Biomacromolecules CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China university of chinese Academy of Sciences Beijing 100049China

Lipid droplets （LDs） are highly conserved multifunctional cellular organelles and aberrant lipid storage in LDs can lead to many metabolic diseases. However, the molecular mechanisms governing lipid dynamic changes remain elusive, and the high-throughput screen of genes influencing LD morphology was limited by lacking specific LD marker proteins in the powerful genetic tool caenorhabditis elegons. In this study, we established a new method to conduct whole-genome RNAi screen using LD resident protein DHS-3 as a LD marker, and identified 78 genes involved in significant LD morphologic changes. Among them, mrhf-1, as well as a series of methylation-related genes, was found dramatically influencing lipid metabolism. SREBP-1 and ScD1 homologs in c. elegans were involved in the lipid metabolic change of rnthf-1（RNAi） worms, and the regulation of ATGL-1 also contributed to it by decreasing triacylglycerol （TAG） hydrolysis. Overall, this study not only identified important genes involved in LD dynamics, but also provided a new tool for LD study using c. elegans, with implications for the study of lipid metabolic diseases.

关键词： Lipid droplet c.elegans RNAi screen Lipid metabolism One-carbon metabolism

Sources and Deficiency Diseases of Mineral Nutrients in Human Health and Nutrition:A Review

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Pedosphere 2014年第1期24卷 13-38页

作者： u.c.GuPTA S.c.GuPTA Agriculture and Agri-canada canada Crops and Livestock Research Centre The Department of Plastic Surgery Loma Linda University

Mineral nutrients are fundamentally metals and other inorganic compounds. The life cycle of these mineral nutrients begins in soil, their primary source. Soil provides minerals to plants and through the plants the minerals go to animals and humans; animal products are also the source of mineral nutrients for humans. Plant foods contain almost all of the mineral nutrients established as essential for human nutrition. They provide much of our skeletal struc.ure, e.g., bones and teeth. They are critical to c.untless body processes by serving as essential co-factors for a number of enzymes. Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption. Though mineral nutrients are essential nutrients, the body requires them in small, precise amounts. We require them in the form found in crops and they can be classified into three different categories： major, secondary, and micro or trace minerals. This classification is based upon their requirement rather than on their relative importance. Major minerals such as potassium （K） and phosphorus （P） are required in amounts of up to 10 g d-1. The daily requirement of secondary and micro minerals ranges from 400 to 1 500 mg d-1 and 45 ~tg d-1 to 11 mg d-1, respectively. To protect humans from mineral nutrient deficiencies, the key is to consume a variety of foods in modest quantities, such as different whole grains, low fat dairy, and different meats, vegetables and fruits. For insurance purposes, a supplement containing various mineral nutrients can be taken daily.

关键词： deficiency diseases deficiency symptoms origin recommended daily dose toxicity

Effect of benzaldehyde on the electrodeposition and corrosion properties of Ni–W alloys

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1060-1066页

作者： u.Pramod Kumar c.Joseph Kennady Department of chemistry Karunya Institute of Technology and SciencesKarunya NagarCoimbatore 641114Tamil NaduIndia

The effect of different concentrations of benzaldehyde on the electrodeposition of Ni–W alloy coatings on a mild steel substrate from a citrate electrolyte was investigated in this study. The electrolytic alkaline bath(p H 8.0) contained stoichiometric amounts of nickel sulfate, sodium tungstate, and trisodium citrate as precursors. The corrosion resistance of the Ni–W-alloy-coated specimens in 0.2 mol/L H2SO4 was studied using various electrochemical techniques. Tafel polarization studies reveal that the alloy coatings obtained from the bath containing 50 ppm benzaldehyde exhibit a protection efficiency of 95.33%. The corrosion rate also decreases by 21.5 times compared with that of the blank. A higher charge-transfer resistance of 1159.40 ?·cm2 and a lower double-layer capacitance of 29.4 μF·cm-2 further confirm the better corrosion resistance of the alloy coating. X-ray diffraction studies reveal that the deposits on the mild steel surface are consisted of nanocrystals. A lower surface roughness value(Rmax) of the deposits is confirmed by atomic force microscopy.

关键词： nickel–tungsten alloys benzaldehyde electrodeposit