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植物激素对棉花蕾铃脱落的调控研究进展

作物学报 2025年第1期51卷 1-29页

作者：谢章书谢学方屠小菊刘爱玉董合忠周仲华湖南农业大学农学院/作物生理与分子生物学教育部重点实验室湖南长沙410128 中国热带农业科学院橡胶研究所海南海口571101 山东省农业科学院经济作物研究所山东济南250000

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于... 详细信息

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于乙烯和脱落酸对棉花蕾铃脱落影响的初步发现。结合其他植物的研究结果来看,蕾铃脱落似乎与生长素、赤霉素和细胞分裂素等促生长类激素的下降以及乙烯和脱落酸等抑制生长类激素的升高密切相关,激素在植物体内不仅介导新陈代谢过程,还协调着与信号通路相关的调控因子,在脱落过程中起着关键作用。本文从植物激素调控入手,综述了近年来包括脱落区形成和作用的分子调控机制以及各激素在棉花蕾铃脱落以及其他植物(生殖)器官脱落过程中的响应和调控机制等。发现目前以棉花蕾铃脱落为对象的研究非常匮乏,且多集中于少数激素对棉花生殖生长影响的有限研究,缺乏对导致蕾铃脱落的深层次机制的探究和解析。因此,未来研究方向应着重于探究棉花蕾铃脱落的遗传基础、发掘新的抗脱落基因资源和培育抗脱落棉花品种,同时加强在以棉花为模型植物下,蕾铃脱落与植物激素调节的关系研究,为提高棉花产量提供理论依据和技术支持。

关键词：棉花植物激素蕾铃脱落研究现状研究方向

Photocatalytic Synthesis of Hydrocarbon Oxygenates from C_2H_6 and CO_2 over Pd-MoO_3/SiO_2 Catalyst

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Journal of Natural Gas Chemistry 2007年第2期16卷 173-178页

作者： Xitao Wang zhong he Shunhe zhong Xiufen Xiao College of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

Pd-MoO3/SiO2 catalyst has been prepared using the method of incipient wetness impregnation. The photo absorbing behaviors and chemisorbing properties of the catalyst have been characterized by UV-vis spectra and TPD-MS experiments. The results indicated that metal Pd loaded on MoOa/SiO2 has a significant effect on the photo absorbing performance of MoOa/SiO2, and an obvious blue shift of the absorption edge is produced. Under UV irradiation, the chemisorption state of CO2 undergoes decomposing process to form CO at 481 K, and a two-site adsorption state of ethane can be formed at around 496 K. Photo-oxidation of ethane using carbon dioxide can mainly produce propanal, ethanol and acetaldehyde in the temperature range of 353-423 K. The presence of metal Pd improves the catalytic activity remarkably.

关键词： photo-catalysis carbon dioxide ethane hydrocarbon oxygenates Pd-MoOa/SiO2 catalyst

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO2 and NiMo/Al2O3 catalysts

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Frontiers of Chemical Science and Engineering 2014年第3期8卷 369-377页

作者： zhong he Xianqin WANG Department of Chemical Biological and Pharmaceutical Engineering New Jersey Institute of Technology Newark NJ 07102 USA

Abstract Catalysts Pt/TiO2 and NiMo/Al2O3 are highly active and selective for the hydrodeoxygenation of guaiacol in a fixed bed reactor at 300℃ and 7.1 MPa, leading to the hydrogenation of aromatic ring, followed by demethylation and dehydroxylation to produce cyclohexane. For a complete hydrodeoxygenation of guaiacol, metal sites and acid sites are required. NiMo/Al2O3 and Pt/ Al2O3 are more active and selective for cyclohexane formation as compared with Pt/TiO2 at 285 Al2O3 and 4 MPa. However, Pt/TiO2 is stable while the other two catalysts deactivate due to the nature and amount of coke formation during the reaction.

关键词： Pt/TiO2 NiMo/Al2O3 Pt/Al2O3 bio-oil,hydrodeoxygenation guaiacol cyclohexane

Hydrogen Bonding Effects on the Photophysical Properties of 2,3-dihydro-3-keto- 1H-pyrido[3,2,1-kl] phenothiazine

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Chinese Journal of Chemical Physics 2012年第3期25卷 254-260,373页

作者： Song-qiu Yang Guo-zhong he State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 115023 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Time-dependent density functional theory （TDDFT） and femtosecond transient absorption spectroscopy were used to investigate the photophysical properties of 2,3-dihydro-3-keto-lH- pyrido[3,2,1-kl]phenothiazine （PTZ4） and 3-keto-lH-pyrido[3,2,1-kl]phenothiazine （PTZ5）. The calculated results obtained from TDDFT suggest that the red-shifts of the absorption spectra of these two fluorophores in methanol are due to the formation of hydrogen-bonded complexes at the ground state. Four conformers of PTZ4 were obtained by TDDFT. The two fluorescence peaks of PTZ4 in tetrahydrofuran （THF） came from the ICT states of the four conformers. The fluorescence of PTZ4 in THF showed a dependence on the excitation wavelength because of butterfly bending. The excited state dynamics of PTZ4 in THF and methanol were obtained by transient absorption spectroscopy. The lifetime of the excited PTZ4 in methanol was 53.8 ps, and its relaxation from the LE state to the ICT state was completed within several picoseconds. The short lifetime of excited PTZ4 in methanol was due to the formation of out-of-plane model hydrogen bonds between PTZ4 and methanol at the excited state.

关键词： 2,3-dihydro-3-keto-lH-pyrido[3,2,1-kl]phenothiazine Time-dependent densityfunctional theory Femtosecond transient absorption spectroscopy Hydrogen bonding effect

A Self-Excitation Double Pathway Relaxation Oscillational Model of Rare-Earth-Doped Laser

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Chinese Physics Letters 1996年第4期13卷 281-284页

作者： WANG zhong-he ZHANG Guang-yin Department of Physics Nankai UniversityTianjin 300071

A self-excitation double pathway relaxation oscillation mechanism to deal with the seif-pulsing output of up conversion laser with rare-earth ions as the active material is *** reabsorption of the laser signal,which causes self-excitation of system and two-pathway transition of systepi,plays a role of adjusting Q,and causes the oscillation output of laser.A qualitative analysis to the appearance of self-pulsing output of rare-earth-doped laser is given.

关键词： oscillation excitation rare

Holocene Dune Mobility and Forcing Mechanisms at the Northern Margin of the East Asian Monsoon

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Acta Geologica Sinica(English Edition) 2013年第4期87卷 1168-1178页

作者： he zhong ZHOU Jie YANG Linhai he Hongming Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resource Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Dune fields at the northern margin of the East Asian monsoon （EAM）, are mosaics of mobile and vegetation-stabilized aeolian dunes. These sand dunes are highly sensitive to environmental change, thus the distribution and the timing of their development may provide important clues to past environmental dynamics. Due to the strong wind erosion and dune migration, long and continuous stratigraphic records are seldom preserved. Synthesizing a large body of events, ultimately producing a relatively complete and high-resolution record, may be a proper method to investigate the dune development history and climate change. In this study, we synthesized a large body of luminescence ages for aeolian deposits from the Mu Us, Otindag, Horqin dune fields at the northern margin of the EAM. The results show that these dune fields, as a whole experienced a most extensive mobility during the early Holocene, followed by a widespread shift toward limited mobility and soil development in the mid-Holocene, and widespread reactivation occurred during late Holocene. The dune developments are directly linked to the effective moisture change controlled by the EAM changes, which respond to the low latitude summer insolation variation. The increased subsidence at the margin contrary to the core EAM, the delay from the feedback of the soil-vegetation-air coupled system, the increased evaporation due to the high temperature all play partial role in the lag of the margin EAM effective moisture change to the low latitude summer insolation. The asynchronous end of the wetter mid-Holocene mainly responds to the southeastwardly shift of the precipitation belt, while the regional sensitivity, response speed and internal feedback also contributed. The correspondence between dune records and North Atlantic drift-ice records of the rapid climate changes implies a close relationship between North Atlantic climate and the frequent dune activity at the northern margin of EAM.

关键词： Holocene dune mobility luminescence dating East Asian Monsoon forcing mechanisms

Magnetometer-only linear attitude estimation for bias momentum pico-satellite

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 455-464页

作者： Ke HAN Hao WANG zhong-he JIN Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

Satellite attitude information is essential for pico-satellite applications requiring light-weight,low-power,and fast-computation *** objective of this study is to provide a magnetometer-only attitude estimation method for a low-altitude Earth orbit,bias momentum *** on two assumptions,the spacecraft spherical symmetry and damping of body rates,a linear kinematics model of a bias momentum satellite's pitch axis is derived,and the linear estimation algorithm is *** algorithm combines the linear Kalman filter(KF) with the classic three-axis attitude determination method(TRIAD).KF is used to estimate satellite's pitch axis orientation,while TRIAD is used to obtain information concerning the satellite's three-axis *** tests confirmed that the algorithm is suited to the time-varying model errors resulting from both *** estimate result keeps tracking satellite attitude motion during all damping,stable,and free rotating control *** with nonlinear algorithms,such as extended Kalman filer(EKF) and square root unscented Kalman filer(SRUKF),the algorithm presented here has an almost equal performance in terms of convergence time and estimation accuracy,while the consumption of computing resources is much lower.

关键词： Pico-satellite Attitude estimation Bias momentum Magnetometer Kalman filter(KF)

Toeplitz Operators with BMO Symbols of Several Complex Variables

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Acta Mathematica Sinica,English Series 2012年第3期28卷 599-608页

作者： zhong Hua he Guang Fu CAO School of Mathematics and Information Sciences Guangzhou University

In this note we prove that the boundedness and compactness of the Toeplitz operator on the Bergman space L2a （Bn） for several complex variables with a BMO1 symbol is completely determined by the boundary behavior of... 详细信息

关键词： Toeplitz operator Bergman space Berezin transform

Probing the new strategy for the oral formulations of taxanes:changing the method with the situation

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Chinese Journal of Natural Medicines 2021年第9期19卷 656-665页

作者： WANG he-Lin SUN Jin TIAN Chu-Tong he zhong-Gui Department of Pharmaceutics Wuya College of InnovationShenyang Pharmaceutical UniversityShenyang 110016China

The first-generation taxanes(including paclitaxel and docetaxel)are widely used for the treatment of various cancers in clinical *** the past decade,a series of new-generation taxanes have been developed which are effective in the inhibition of tumor ***,intravenous(i.v.)infusion is still the only route of administration,and may result in serious adverse reactions with respect to the utilization of Cremophor EL or Tween-80 as ***,the dosing schedule is also ***,oral administration of taxanes is urgently needed to avoid the adverse reactionss and increase dosing *** this review,we first outlined the discovery and development of taxane-based anticancer ***,we summarized the research progress on the oral formulations of taxanes and proposed some thoughts on the future development of oral taxane formulations.

关键词： Taxanes Oral delivery Oral bioavailability Anti-tumor