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Effect of Media on the Electric Field of a Rhombic Nanostructure Array

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Chinese Physics Letters 2010年第6期27卷 217-220页

作者： ZHU Shao-li zhou wei Precision Engineering and Nanotechnology Centre School of Mechanical and Aerospace Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798

Electric field distribution is an important parameter for nanostructure arrays in nanobiosensing appfications. It can influence the sensitivity and the resolution of nanobiosensors. We focus on the effect of media on the electric field distribution of a rhombic silver nanostructure array. The finite-difference time-domain algorithm- based numerical calculation method is used to monitor the electric field distribution of the silver nanostructures when the refractive index of the medium around the nanostructure array is changed. The calculated results show that tuning the refractive index of the medium around silver can have a considerable influence on the electric field distribution in the reflection and transmission directions. This effect can be used to increase the extinction efficiency and to improve the resolution of the spectra for nanobiosensing.

关键词： ELECTRIC fields NANOSTRUCTURES RHOMBIC antennas BIOSENSORS SENSITIVITY analysis FINITE differences TIME-domain analysis NUMERICAL calculations

Screening of Amaranth Cultivars(Amaranthus mangostanus L.) for Cadmium Hyperaccumulation

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Agricultural Sciences in China 2009年第3期8卷 342-351页

作者： FAN Hong-li zhou wei Key Laboratory of Crop Nutrition and Fertilization Ministry of Agriculture~Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences Beijing 100081 P.R. China

The potential harm of soil cadmium pollution to ecological environment and human health has been increasingly widely concerned. Phytoremediation, as a kind of new and effective technology, has become an important method for cleaning up cadmium in contaminated sites. The amaranth （Amaranthus mangostanus L.） is widely distributed and has abundant varieties in China, its rapid growth and large biomass can be served as candidate for cadmium hyperaccumulators for phytoremediation. To obtain cadmium hyper-accumulator, Cd uptake in 23 amaranth cultivars from different ecological region was investigated under hydroponic culture condition. Meanwhile, pot experiment was established to probe phytoremediation potentiality of Cd contaminated soil by amaranth. Three treatment （Cd 5, 10, and 25 mg kg^-1） were imposed to red soil, yellow brown soil, and vegetable soil. The results showed that under hydroponic culture with Cd 3 mg L^-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 260 mg kg^-1, and its total cadmium uptake was the highest among various cultivars. In the treatment Cd 25 mg kg^-1, the cadmium concentration in the shoots of the cultivar Tianxingmi reached 212 mg kg^-1, while bioaccumulation factor and shoot purification rate reached 8.50 and 3.8%, respectively. Further, the total biomass and shoot biomass were not decreased significantly under Cd exposure. These results suggested that cultivar Tianxingmi is a typical Cd hyperaccumulator, and can be expected to be used in phytoremediation of Cd contaminated soil.

关键词： cadmium hyperaccumulation amaranth phytoremediation

Brassinosteroids Regulate the Differential Growth of Arabidopsis Hypocotyls through Auxin Signaling Components IAA19 and ARF7

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Molecular Plant 2013年第3期6卷 887-904页

作者： Xiao-Yi zhou li Song Hong-wei Xue National Key Laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 300 Fenglin Road 200032 Shanghai China

Brassinosteroids （BRs） are an important class of phytohormones which regulates a wide range of physiological processes. Genetic and physiological studies have revealed that BR responses usually depend on an intact auxin signaling pathway. Here, we demonstrate that high BR concentration or enhanced BR signaling induce the differential growth of etiolated hypocotyls and result in the morphological changes, while auxin-resistant mutants, msg2 （dominant mutant of IAA19） and arf7, are insensitive to the BR effect and can partially suppress the phenotype of bzrl-D （dominant mutant of BZR1 with enhanced BR signaling）. Interestingly, BZR1 protein can directly bind to the promoter regions of both IAA19 and ARFT, indicating that IAA19 and ARF7 mediate the BR-induced differential growth by serving as direct targets of BZR1. Systemic microarray analysis revealed that a number of BR-responsive genes showed reduced BR response in msg2, confirming that BR employs auxin signaling components IAA19 and ARF7 to modulate the specific downstream processes. These results provide informative clues on the crosstalk of BR-auxin signaling and the mechanisms of BR-auxin effects in regulating differential growth.

关键词： brassinosteroids (BRs) auxin IAA19 ARF7 differential growth Arabidopsis.

Layered MAP algorithm for MIMO ISI channels

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 19-23页

作者： MO Yong zhou Xing-wei li Dao-ben School of Information Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

The layered maximum a posteriori （L-MAP） algorithm has been proposed to detect signals under frequency selective fading multiple input multiple output （MIMO） channels. Compared to the optimum MAP detector, the L-MAP algorithm can efficiently identify signal bits, and the complexity grows linearly with the number of input antennas. The basic idea of L-MAP is to operate on each input sub-stream with an optimum MAP sequential detector separately by assuming the other streams are Gaussian noise. The soft output can also be forwarded to outer channel decoder for iterative decoding. Simulation results show that the proposed method can converge with a small number of iterations under different channel conditions and outperforms other sub-optimum detectors for rank-deficient channels.

关键词： MIMO L-MAP Bahl-Cocke-Jelinek-Raviv (BCJR) algorithm soft-in soft-out

Impact of supercritical adsorption mechanism on research of hydrogen carrier

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Chinese Science Bulletin 2007年第8期52卷 1146-1152页

作者： SUN Yan zhou li SU wei zhou YaPing Adsorption Laboratory of the Key State Laboratory of Chemical Engineering Tianjin University Tianjin 300072 China

Hydrogen storage receives the worldwide attention due to its importance in sustainable energy and the solution of greenhouse *** provides an efficient way to compress gases and,therefore, has been applied to the development of hydrogen storage ***,hydrogen is a super- critical gas at the temperature of engineering interest and follows a different adsorption mechanism compared to the sub-critical *** present work shows why only monolayer coverage mechanism functions at above-critical temperatures and what consequences will result in the application study. Although there are pros and cons to this point of view,understanding the adsorption mechanism is,in- deed,essential for the research of hydrogen storage method since it claims that any storage material based on adsorption will not satisfy the practical need of on board storage no matter how novel the material is.

关键词：超临界吸附机制氢能载体储氢材料

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(Technological Sciences) 2024年第5期67卷 1443-1457页

作者： zhou QianQian wei YueGuang zhou YiChun YANG li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

The 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-YSZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-YSZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-YSZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

Studies on the Crystal Structure and Photoluminescence of a Mercury(Ⅱ)Complex Based on a Novel Pyridine ligand

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1029-1032页

作者： WU Jie-Ying zhou Wen li wei-Jie zhou Hong-Ping TIAN Yu-Peng Department of Chemistry Key Laboratory of Functional Inorganic Materials Chemistry of Anhui Province Anhui University Hefei 230039 China

A novel mercury（H） complex HgL2Br2 was prepared from HgBr2 and the organic ligand 2-（N-methyl-N-（4-（（E）-2-（pyridine-4-yl）vinyl）phenyl）amino）ethanol （L）. The ligand was synthesized and then characterized by FT-IR spectroscopy, tH NMR, mass spectrum and elemental analysis, while the single-crystal diffraction data of the complex were collected on a Siemens Smart CCD diffractometer. The complex crystallizes in triclinic space group PI with a = 5.367（5）, b = 12.466（5）, c = 23.945（5） A, α = 90.812（5）, β = 96.318（4）, γ = 96.093（5）°, Z = 2, Dc = 1.817 ***3,μ = 7.395 mm^-1, S = 0.825, and the final R= 0.0396. The Hg（Ⅱ） ion in the distorted tetrahedral mercury（Ⅱ） complex C32H36HgBr2N4O2 is coordinated by two N atoms from the two ligands together with two bromide ions. Solid-state emission of the ligand and its complex has been investigated at room temperature.

关键词： mercury(Ⅱ) complex single-photon fluorescence crystal structure

Sesquiterpenes and polyphenols with glucose-uptake stimulatory and antioxidant activities from the medicinal mushroom Sanghuangporus sanghuang

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Chinese Journal of Natural Medicines 2021年第9期19卷 693-699页

作者： ZHANG Jin-Jin CHEN Bao-Song DAI Huan-Qin REN Jin-wei zhou li-wei WU Sheng-Hua liU Hong-wei State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Savaid Medical School University of Chinese Academy of SciencesBeijing 100049China Department of Biology National Museum of Natural ScienceTaichung 40453TaiwanChina

A chemical investigation on the fermentation products of Sanghuangporus sanghuang led to the isolation and identification of fourteen secondary metabolites(1-14)including eight sesquiterpenoids(1-8)and six polyphenols(9-14).Compounds1-3 were sesquiterpenes with new structures which were elucidated based on NMR spectroscopy,high resolution mass spectrometry(HRMS)and electronic circular dichroism(ECD)*** the isolates were tested for their stimulation effects on glucose uptake in insulin-resistant HepG2 cells,and cellular antioxidant *** 9-12 were subjected to molecular docking experiment to primarily evaluate their anti-coronavirus(SARS-CoV-2)*** a result,compounds 9-12 were found to increase the glucose uptake of insulin-resistant HepG2 cells by 18.1%,62.7%,33.7%and 21.4%at the dose of 50μmol·L^(-1),*** 9-12 also showed good cellular antioxidant activities with CAA_(50)values of 12.23,23.11,5.31 and 16.04μmol·L^(-1),*** docking between COVID-19 M^(pro)and compounds 9-12 indicated potential SARS-CoV-2 inhibitory activity of these four *** work provides new insights for the potential role of the medicinal mushroom *** as drugs and functional foods.

关键词： Sanghuangporus sanghuang Sesquiterpenoids Polyphenols Glucose-uptake stimulation Cellular antioxidant activity Anti-coronavirus activity

A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： wei-lin Huang Yan-Xin zhou Yang zhou wei-Jie liu Ji-Dong li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction