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Population suppression of Bemisia tabaci （Hemiptera： Aleyrodidae） using yellow sticky traps and Eretmocerus nr. rajasthanicus （Hymenoptera： Aphelinidae） on tomato plants in greenhouses

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Insect Science 2008年第3期15卷 263-270页

作者： xi-shu gu Wen-Jun Bu Wei-Hong Xu Yi-Chuan Bai Bai-Ming Liu Tong-xian Liu Coflege of Life Science Nankai University Tianjin China Institute of Plant Protection Tianjin Academy of Agricultural Science Tianjin China Department of Entomology Texas AgriLife Research Texas A&M University System Weslaco Texas 78596 USA

We conducted three experiments for management of Bemisia tabaci （Gennadius） biotype＇ B＇ on tomatoes under greenhouse conditions：（i） vertically placing yellow sticky cards either parallel or perpendicular to tomato rows at a rate of 1 per 3-m row; （ii） releasing Eretmocerus sp. nr. rajasthanicus once at 30 adults/m2 in the high whitefly density greenhouses （〉 10 adults/plant）, or twice at 15 adults/m2 at a 5-day interval in the low whitefly density greenhouses （〈 10 adults/plant）; and （iii） using combinations of yellow sticky cards that were placed vertically parallel to tomato rows and parasitoids released once at 30/m2 in high whitefly density greenhouses or twice at 15/m2 at a 5-day interval in low whitefly density greenhouses. Our data show that yellow sticky cards trapped B. tabaci adults and significantly reduced whitefly populations on tomato. The yellow sticky cards that were placed parallel to tomato rows caught significantly more whitefly adults than those placed perpendicular to tomato rows on every sampling date. In the treatment where parasitoids were released once at 30/m2 in high whitefly density greenhouses, the number of live whitefly nymphs were reduced from 4.6/leaf to 2.9/leaf in 40 days as compared with those on untreated plants on which live whitefly nymphs increased from 4.4/leaf to 8.9/leaf. In the treatment where parasitoids were released twice at 15/m2 in low whitefly density greenhouses, the numbers of live nymphs ofB. tabaci on tomato leaves were reduced from 2.1/leaf to 1.7/leaf in 20 days as compared with those on untreated plants on which numbers of live nymphs ofB. tabaci increased from 2.2/leaf to 4.5/leaf. In the treatment of yellow sticky cards and parasitoid release once at 30/m2 in high whitefly density greenhouses, the numbers of live nymphs of B. tabaci on tomato leaves were reduced from 7.2/leaf to 1.9/leaf, and in the treatment of yellow sticky cards and parasitoid release twice at 15/m2 at a 5-day interval at low whitefly de

关键词： greenhouses parasitoids physical control sweetpotato whitefly yellowsticky cards

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Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling guo shun-xi Li Yu-Cheng Liu Yu-Long Li Wei shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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锗锡浓度对硅锗锡合金性能影响的研究

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原子与分子物理学报 2025年第5期42卷 163-174页

作者：顾永顺温淑敏内蒙古工业大学理学院呼和浩特010051

由于SiGeSn合金材料其具有高的载流子迁移率和较长的载流子寿命,并且其结构具有较高的热力学稳定性,所以在光电子领域中是一种具有非常大应用潜力的半导体材料.本文采用密度泛函理论中的广义梯度近似GGA+U的方法,构建并计算了本征半导体... 详细信息

由于SiGeSn合金材料其具有高的载流子迁移率和较长的载流子寿命,并且其结构具有较高的热力学稳定性,所以在光电子领域中是一种具有非常大应用潜力的半导体材料.本文采用密度泛函理论中的广义梯度近似GGA+U的方法,构建并计算了本征半导体Si_(96)与五组掺杂模型Si_(92)Ge_(2)Sn_(2)、Si_(88)Ge_(4)Sn_(4)、Si_(84)Ge_(6)Sn_(6)、Si_(80)Ge_(8)Sn_(8)、Si_(76)Ge_(10)Sn_(10)的电子结构及光学性质.通过对计算结果的分析可知,Ge,Sn的加入使得Si材料的带隙宽度减小,并且发生了由间接带隙向直接带隙的转变;Ge,Sn浓度最高的SiGeSn合金的形成能相对较高,稳定性相较于Ge,Sn含量低的材料较差;随着Ge,Sn掺杂浓度的提高,电子态密度图显示出越来越明显的杂化现象,并且态密度的峰值主要有Si原子的s轨道提供;Ge,Sn浓度的提高还使得SiGeSn合金的吸收系数在可见光及近红外区域内增加、反射率在可见光及以上波段范围内提高、折射率变低、消光系数曲线向红外区域移动等光学性质变化,表明可以通过调节Ge,Sn浓度来获得合适的光学特性,这为SiGeSn半导体在红外区域光电材料和器件的应用上提供了研究方向.

关键词： SiGeSn 电子特性光学性质

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Palladium-Catalzyed Atroposelective 16-Membered Macrocyclization: Total Synthesis of lsoplagiochin D

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Chinese Journal of Chemistry 2020年第10期38卷 1081-1085页

作者： Junwei xi Zhenhua gu Hefei National Laboratory for Physical Sciences ot the Microscale and Department of ChemistryUniversity of Science and Technology of China96 Jinzhai RoodHefeiAnhui 230026China Center for Excellence in Molecular Synthesis of CAS HefeiAnhui 230026China

Summary of main observation and conclusion Isoplagiochin D is a ring-strained macrocyclic bisbibenzylis,which showed stable axial chirality in one biaryl structure,and semistable axial chirality in the other biaryl *** reported here an unprecedented example for the catalytically asymmetric synthesis of ring-strained atropisomers via Pd-catalyzed macrocyclization between benzyl halides and *** newly developed Pd-catalyzed asym-metric macrocyclization protocol enabled us a quick synthesis of isoplagiochin D in a highly enantioselective manner.

关键词： cyclization benzyl catalyzed

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Modified bottleneck-based heuristic for large-scale job-shop scheduling problems with a single bottleneck

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Journal of Systems Engineering and Electronics 2007年第3期18卷 556-565页

作者： Zuo Yan gu Hanyu xi Yugeng Inst. of Automation Shanghai Jiaotong Univ. Shanghai 200240 P. R. China

A modified bottleneck-based （MB） heuristic for large-scale job-shop scheduling problems with a welldefined bottleneck is suggested, which is simpler but more tailored than the shifting bottleneck （SB） procedure. In this algorithm, the bottleneck is first scheduled optimally while the non-bottleneck machines are subordinated around the solutions of the bottleneck schedule by some effective dispatching rules. Computational results indicate that the MB heuristic can achieve a better tradeoff between solution quality and computational time compared to SB procedure for medium-size problems. Furthermore, it can obtain a good solution in a short time for large-scale jobshop scheduling problems.

关键词： job shop scheduling problem bottleneck shifting bottleneck procedure.

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Raster-scanning Donut simplifies MINFLUX and provides alternative implement on other scanning-based microscopes

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Light(Science & Applications) 2022年第10期11卷 2271-2275页

作者： xinzhu Xu shu Jia Peng xi Department of Biomedical Engineering College of Future TechnologyPeking UniversityBeijing 100871China Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory UniversityAtlantaGeorgia 30332USA UTS-SUStech Joint Research Centre for Bio-medical Materials&Devices Department of Biomedical EngineeringCollege of EngineeringSouthern University of Science and TechnologyShenzhenGuangdong 518055China National Biomedical Imaging Center Peking UniversityBeijing 100871China

A donut excitation moves around a single molecule with a zigzag configuration lattice by *** a method implemented in scanning fluorescence microscopy simplifies the conventional MINFLUX *** of hollow zero-intensity excitation,single-pixel detection,time-correlated single photon counting,and drift stabilization,the system achieves localization precision and resolution very close to conventional MINFLUX theoretically and *** averaged high-SNR reference,and pixel-registered intensity from a single molecule is essential to reconstruct localization in maximum likelihood *** performance reaching nearly conventional MINFLUX's,the proposed raster-scanning MINFLUX can inspire researchers expertized in STED or confocal setup to quickly transform to MINFLUX and develop for further exploring on bio-specimens or optical applications.

关键词： scanning excitation stabilization

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Synthesis and Properties of Reversible Disulfide Bond-based Self-healing Polyurethane with Triple Shape Memory Properties

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Chinese Journal of Polymer Science 2019年第11期37卷 1119-1129页

作者： Han Jia Kun Chang shu-Ying gu Department of Polymeric Materials School of Materials Science and Engineering Tongji University Shanghai 201804 China Key Laboratory of Advanced Civil Engineering Materials Ministry of Education Tongji University Shanghai 201804 China

A reversible disulfide bond-based self-healing polyurethane with triple shape memory properties was prepared by chain extending of random copolymer poly(lactide-co-caprolactone)(PCLA), hexamethylene diisocyanate (HDI), polytetrahydrofuran (PTMEG), and 4,4,-aminophenyl disulfide. The chemical structures were characterized using 1H nuclear magnetic resonance (^1H-NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC). The thermal properties, selfhealing properties, triple-shape memory effect, and quantitative shape memory response were evaluated by differential scanning calorimetry (DSC), tensile tests, two-step programming process thermal mechanical experiments, and subsequent progressive thermal recovery. The self-healing mechanism and procedures were investigated using polarizing optical microscopy (POM) and an optical profiler. It was concluded that self-healing properties (up to 60%) and triple-shape memory properties around 35 and 50℃(with shape fixation ratios of 94.3% and 98.3%, shape recovery ratios of 76.6% and 85.1%, respectively) were integrated to the shape memory polyurethane. As-prepared polyurethane is expected to have potential applications in multi-shape coatings, films, and step-by-step deploying structures.

关键词： Self-healing Reversible disulfide bond Triple shape memory Polyurethane

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Study of parametric roll in oblique waves using a three-dimensional hybrid panel method

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Journal of Hydrodynamics 2020年第1期32卷 126-138页

作者： Min gu shu-xia Bu Jiang Lu Jiangsu Key Laboralory of Green Ship Technology China Ship Scientific Research CenterWiuxi 214082.China

A reliable numerical tool for the prediction of the parametric roll is important in the development of the second generation intact stability *** main difficulty of the prediction of the parametric roll comes from the significant coupling of the roll with other motions,especially the heave and pitch *** this paper,the numerical method for determining the parametric roll is studied and the results are benchmarked against the model test ***,a 3 degrees-of-freedom(DOF)time domain hybrid panel method is validated by experimental data in regular oblique waves and irregular head ***,the verified 3D O F method is extended to a fully coupled 6 DOF method with the course ***,taking the C11 containership as the test case,the parametric roll in oblique waves is computed,and the effects of the surge,sway and yaw motions on the parametric roll are evaluated with the developed mathematical *** results show that the effects of the surge and sway motions on the parametric roll is insignificant,while the effects of the yaw motion are more *** results of the roll amplitudes and the standard deviation of the roll angles show that the model based on 3 DOF gives relatively conservative results,and can be directly used for the stability assessment of the parametric roll.

关键词： 6DOF mathematical model irregular oblique waves second generation intact stability in IMO

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On the anomalous low-resistance state and exceptional Hall component in hard-magnetic Weyl nanoflakes

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 107-113页

作者： QingQi Zeng GangXu gu Gang Shi JianLei Shen Bei Ding shu Zhang XueKui xi Claudia Felser YongQing Li EnKe Liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Department of Physics and Astronomy University of CaliforniaLos Angeles 90095USA Max Planck Institute for Chemical Physics of Solids Dresden D-01187Germany Songshan Lake Materials Laboratory Dongguan 523808China

Magnetic topological materials, which combine magnetism and topology, are expected to host emerging topological states and exotic quantum phenomena. In this study, with the aid of greatly enhanced coercive fields in high-quality nanoflakes of the magnetic Weyl semimetal Co_(3)Sn_(2)S_(2), we investigate anomalous electronic transport properties that are difficult to reveal in bulk Co_(3)Sn_(2)S_(2) or other magnetic materials. When the magnetization is antiparallel to the applied magnetic field, the low longitudinal resistance state occurs, which is in sharp contrast to the high resistance state for the parallel case. Meanwhile, an exceptional Hall component that can be up to three times larger than conventional anomalous Hall resistivity is also observed for transverse transport. These anomalous transport behaviors can be further understood by considering nonlinear magnetic textures and the chiral magnetic field associated with Weyl fermions, extending the longitudinal and transverse transport physics and providing novel degrees of freedom in the spintronic applications of emerging topological magnets.

关键词： hard-magnetic material magnetic Weyl semimetal magnetoresistance Hall effect

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Effect of Trace Addition of Ceramic on Microstructure Development and Mechanical Properties of Selective Laser Melted AlSi10Mg Alloy

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 56-68页

作者： Yuxin Li Dongdong gu Han Zhang Lixia xi College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Selective laser melting(SLM)is an emerging additive manufacturing technology for fabricating aluminum alloys and aluminum matrix ***,it remains unclear how to improve the properties of laser manufactured aluminum alloy by adding ceramic reinforcing *** the effect of trace addition of TiB2 ceramic(1%weight fraction)on microstructural and mechanical properties of SLM-produced AlSi10Mg composite parts was *** densification level increased with increasing laser power and decreasing scan speed.A near fully dense composite part(99.37%)with smooth surface morphology and elevated inter-layer bonding was successfully obtained.A decrease of lattice plane distance was identified by X-ray diffraction with the laser scan speed decreased,which implied that the crystal lattices were distorted due to the dissolution of Si and TiB2 particles.A homogeneous composite microstructure with the distribution of surface-smoothened TiB2 particles was present,and a small amount of Si particles precipitated at the interface between reinforcing particles and *** contrast to the AlSi10Mg alloy,the composites showed a stabilized microhardness distribution.A higher ultimate tensile strength of 380.0 MPa,yield strength of 250.4 MPa and elongation of 3.43%were obtained even with a trace amount of ceramic *** improvement of tensile properties can be attributed to multiple mechanisms including solid solution strengthening,load-bearing strengthening and dispersion *** research provides a theoretical basis for ceramic reinforced aluminum matrix composites by additive manufacturing.

关键词： Selective laser melting TiB2 Aluminum matrix composites Mechanical properties Strengthening mechanism

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