检索结果-南通市图书馆

Journal of Integrative Plant Biology 2005年第11期47卷 1345-1351页

作者： Zhi-Yong XIONG Yong liU Yong-Gang HE Yun-Chun SONG ke-xiu li Guan-Yuan HE China-UK HUST-RRes （Rothamsted Reseach UK） Genetic Engineering and Genomics Joint Laboratory Huazhong University of Science and Technology （HUST） Wuhan 430074 China key Laboratory of the Ministry of Education for Plant Developmental Biology Wuhan University Wuhan 430072 China

Knobs are blocks of heterochromatin present on chromosomes of maize （Zea mays L.） and its relatives that have effects on the frequency of genetic recombination, as well as on chromosome behavior. Knob heterozygosity and instability in six maize inbred lines and one Z. diploperennis Iltis Doebley line were investigated using the fluorescence in situ hybridization （FISH） technique with knob-associated tandem repeats （180 bp and 350 bp （TR- 1）） as probes. Signals of seven heterozygous knobs containing 180- bp repeats and of one heterozygous knob containing TR- 1 were captured in chromosomes of all materials tested according to the results of FISH, which demonstrates that the 180-bp repeat is the main contributor to knob heterozygosity compared with the TR- 1 element. In addition, one target cell with two TR- 1 signals on one homolog of chromosome 2L, which was different from the normal cells in the maize inbred line GB57, was observed, suggesting knob duplication and an instability phenomenon in the maize genome.

关键词： fluorescence in situ hybridization knob repetitive DNA sequence Zea diploperennis Z. mays.

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第5期35卷 74-84页

作者： Sheng-Jie Du xiu-Xia li Yang Tian Yuan-Yuan liu ke Jia Zhong-Zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan li Zheng-Cao li Sha-Sha Lv College of Nuclear Science and Technology Joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment key Laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

Rapid analysis of metal ions and organic compounds in strong acidic solutions by nano-ESI mass spectrometry

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 516-520页

作者： Jiaquan Xu Ting li Zhendong Yu lili Song xiu-xiu Xu Hui li Jiangxi key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China Department of Rehabilitation Medicine The First Affiliated Hospital of Nanchang UniversityNanchang 330006China

Rapid analysis of metal ions and organic compounds in strong acidic solutions is of sustainable interest in multiple ***,complicated and time-consuming pretreatments are always required for MS analysis of the compounds in strong acidic ***,it will result in a weak signal and cause serious damage to the mass ***,a simple method inherited from nano-ESI MS was developed for rapid analysis of strong acidic ***(nL)strong acidic solution was first loaded in the nano-ESI emitter,followed by evaporation to remove the H+and leave the analytes on the wall of the nano-ESI *** evaporation process can be completed within 1 min because of the extremely tiny volume(≤1 nL)of the loaded ***,the dried analytes on the wall of the nano-ESI emitter were redissolved by loading a new solvent,followed by nano-ESI MS *** using this method,metal ions and organic compounds in the strong acidic solution can be detected with low sample consumption(1 nL),high speed(limit of detection=0.2µg/L),and high accuracy(>90%).Proof-of-concept applications of the present method have been successfully achieved for the analysis of gastric juice(pH of the sample=1),monitoring reaction catalyzed by strong acid(pH of the system=0),and micro-area analysis of ores(pH of the extraction solvent=0),showing great application potential in multiple fields.

关键词： Strong acidic solutions Nano-ESI MS Rapid analysis Reaction monitoring Micro-area analysis Gastric juice analysis

Strong Edge Coloring of Outerplane Graphs with Independent Crossings

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 467-477页

作者： ke-Jie li Xin ZHANG School of Mathematics and Statistics Xidian UniversityXi’an 710071China

The strong chromatic index of a graph is the minimum number of colors needed in a proper edge coloring so that no edge is adjacent to two edges of the same *** outerplane graph with independent crossings is a graph embedded in the plane in such a way that all vertices are on the outer face and two pairs of crossing edges share no common end *** is proved that every outerplane graph with independent crossings and maximum degreeΔhas strong chromatic index at most 4Δ-6 if Δ≥4,and at most 8 ifΔ≤*** bounds are sharp.

关键词： outer-1-planar graph IC-planar graph strong edge coloring crossing

Priority effects of forbs arriving early:the role of root interaction and asymmetric competition

在线全文

学校读者我要写书评

暂无评论

Ecological Processes 2024年第1期13卷 53-65页

作者： Xiaohong Yan Xiliang li ke Jin Institute of Grassland Research Chinese Academy of Agricultural Sciences

Background The priority effect of plant arrival is a key driver of community assembly and ecosystem succession during the restoration of degraded plant communities. However, the significance of the arrival order of different plant functional groups and their interactions with community assemblies remains unclear. Using a phytotron experiment with three fully crossed factors, we investigated the underlying mechanisms of priority effects and their relationships with the biomass and biodiversity effects in mixed plant communities by manipulating the order of arrival of species, isolation of roots, and removal of specific *** The results showed that the strength and direction of priority effects were influenced by arrival order, root interactions, asymmetric competition among species, and their interactions. The identities of early and late-sown species also determined the magnitude of priority effects. The priority effects were stronger in grass-first(24.76%) and legume-first communities(24.48%) than in forb-first communities. The pot biomass of the different priority treatments was highest in grass-first(5.85 g), followed by legume-first(3.94 g) and forb-first(2.48 g). The order of arrival in the mixture significantly affected the net biodiversity effects(P lies. In addition, the importance of the priority effect of forbs sown first is related to community assembly, which may be a key determinant in successfully establishing a highly diverse community in the early stages of restoration. Species with weak competition should be considered in the early stage of community ass

关键词： Community assembly Order of arrival Overyielding Plant functional group Root isolation

Preparation of entangledW states based on the cavity QED system

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第9期33卷 290-296页

作者： ke li Jun-Long Zhao Department of Physics Shanghai Second Polytechnic UniversityShanghai 201209China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China

We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)*** to the most current fusion schemes which are conditioned on the case where one particle can be extracted from each initial W state to the fusion process,our scheme will access one or two particles from each W *** on the atom–cavity-field detuned interaction,three jWin+m+t states can be generated from the jWin,jWim,and jWit states with the help of two auxiliary atoms,and three jWin+m+t+q states can be generated from jWin,jWim,jWit,and a jWiq state with the help of three auxiliary *** the numerical simulations of the resource cost of fusing three small-size W states based on the previous schemes,our fusion scheme seems to be more *** QLF fusion scheme can be generalized to the case of fusing k different or identical particle W ***,with no qubit loss,it greatly reduces the number of fusion steps and prepares W states with larger particle numbers.

关键词： W state detuned interaction state fusion cavity quantum electrodynamics

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第1期43卷 236-246页

作者： lin Yang Zhong Zhang Chao-Nan Zhang xiu-li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第1期38卷 42-53页

作者： liU Lei liU Jian-cheng li Xin XU li-xin ZHANG xiu-zhan State key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi YU Wan-li WANG Pi-guang QU Yang DU xiu-li key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

CYP2E1-dependent hepatotoxicity and oxidative damage after ethanol administration in human primary hepatocytes

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2005年第29期11卷 4530-4535页

作者： lie-Gang liu Hong Yan Ping Yao Wen Zhang li-Jun Zou Fang-Fang Song ke li xiu-Fa Sun Department of Nutrition and Food Hygiene School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To observe the relationship between ethanol-induced oxidative damage in human primary cultured hepatocytes and cytochrome P450 2E1 （CYP2E1） activity, in order to address if inhibition of CYP2E1 could attenuate ethanol- induced cellular damage. METHODS： The dose-dependent （25-100 mmol/L） and time-dependent （0-24 h） exposures of primary human cultured hepatocytes to ethanol were carried out. CYP2E1 activity and protein expression were detected by spectrophotometer and Western blot analysis respectively. Hepatotoxicity was investigated by determination of lactate dehydrogenase （LDH） and aspartate transaminase （AST） level in hepatocyte culture supernatants, as well as the intracellular formation of malondialdehyde （MDA）. RESULTS： A dose-and time-dependent response between ethanol exposure and CYP2E1 activity in human hepatocytes was demonstrated. Moreover, there was a time-dependent increase of CYP2E1 protein after 100 mmol/L ethanol exposure. Meanwhile, ethanol exposure of hepatocytes caused a time-dependent increase of cellular MDA level, LDH, and AST activities in supernatants. Furthermore, the inhibitor of CYP2E1, diallyl sulfide （DAS） could partly attenuate the increases of MDA, LDH, and AST in human hepatocytes. CONCLUSION： A positive relationship between ethanolinduced oxidative damage in human primary cultured hepatocytes and CYP2E1 activity was exhibited, and the inhibition of CYP2E1 could partly attenuate ethanol-induced oxidative damage.

关键词： Ethanol CYP2E1 Oxidative damage, Human primary hepatocytes