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Theoretical Studies on the Isomerization of Peroxynitrite to Nitrate Mediated by Peroxynitrous Acid

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Chinese Journal of Structural Chemistry 2008年第2期27卷 171-176页

作者： LIU Yong-dong zhong Ru-Gang College of Life Science ＆ Bioengineering Beijing University of Technology Beijing 100022 China

The conversion of peroxynitrite （ONOO-） to nitrate （NO3-） mediated by peroxynitrous acid （ONOOH） has been investigated at the CCSD/6-311G（d）//B3LYP/6-31 1＋G（d,p） level. Two kinds of pathways for the title reaction were found. The results show that the energy barrier of isomerization through pathway 1 is around 25 kcal/mol in the gas phase. This value is significantly lower than that of isomerization without any catalysts. Thus, it indicates that ONOOH definitely makes the conversion from ONOO- to NO3- feasible. Although pathway 2 does not decrease the energy barrier of this isomerization, peroxynitric acid （O2NOOH） was obtained; moreover, this is a new pathway for this formation. In view of the results that peroxynitrate anion can decompose into nitrite and dioxygen, we conclude that our results are consistent with the experimental observation that nitrate, nitrite, and dioxygen are the main final products of the decay of peroxynitrite around pH 7.

关键词： peroxynitrite peroxynitrous acid isomerization DFT

Experiment of heat transfer in oscillating turbulent flow in a pipe with constant heat flux

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航空动力学报 2013年第9期28卷 1949-1955页

作者： LI Ming-zhen dong Jin-zhong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Heat transfer characteristics of oscillating turbulent air flow in a pipe heated with constant heat flux were experimentally *** experiments were performed over a range of 245.7 to 902 of the kinetic Reynolds number and 25 to 175 of the dimensionless oscillation *** effects of these two dimensionless parameters were *** results show that the cycle-averaged local Nusselt number increases with both the kinetic Reynolds number and the dimensionless oscillation *** space-cycle averaged Nusselt number also effectively increases with the kinetic Reynolds number and the dimensionless oscillation *** on the experimental data,a correlation equation of the space-cycle averaged Nusselt number for air in terms of these two dimensionless parameters has been obtained.

关键词： oscillating turbulent flow heat transfer kinetic Reynolds number Nusselt number constant heat flux

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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

Symmetry Reduction and Exact Solutions of the(3+1)-Dimensional Breaking Soliton Equation

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Communications in Theoretical Physics 2008年第10期50卷 832-840页

作者： WANG Ling dong zhong-Zhou Department of Mathematics and Computer Science Chizhou University Chizhou 247000 China Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai 200062 China Key Laboratory of Mathematics Mechanization Chinese Academy of Sciences Beijing 100080 China

By means of the generalized direct method,a relationship is constructed between the new solutions andthe old ones of the (3+1)-dimensional breaking soliton *** on the relationship,a new solution is obtainedby using a given solution of the *** symmetry is also obtained for the (3+1)-dimensional breaking *** using the equivalent vector of the symmetry,we construct a seven-dimensional symmetry algebra and getthe optimal system of group-invariant *** every case of the optimal system,the (3+1)-dimensional breakingsoliton equation is reduced and some solutions to the reduced equations are ***,some new explicitsolutions are found for the (3+1)-dimensional breaking soliton equation.

关键词： generalized direct method breaking soliton equation optimal system explicit solution

Synergistic Action of fMLP-boanmycin Combination on the Growth of Mouse Colon Carcinoma and Its Action Mechanisms

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Chinese Journal of Cancer Research 2010年第2期22卷 135-140页

作者： zhong-dong Li Yan Gao Department of Pharmacology General Hospital of PLA Air Force Beijing 100142 China

Objective： The inhibitory action of fMLP-boanmycin （BAM） combination on the growth of mouse colon carcinoma and its action mechanisms were observed in order to provide experimental proof for probing novel regimen of chemotactic modulation in combination with chemotherapy in the treatment of cancer. Methods： Cytotoxicity of BAM-fMLP combination to tumor cells was determined by MTT assay in vitro. Antitumor activity of BAM-fMLP combination was assessed in mice subcutaneously transplanted colon carcinoma 26. The amount of superoxide anion （O2 ·^-）released from fMLP stimulated macrophages was determined by NBT assay. The amount of nitric oxide （NO） was indirectly determined by Griess method. Results： BAM-fMLP combination had no synergistic effect on tumor cells（CDI〉0.85）, but BAM at the doses of 10μg/ml, 30μg/ml and 100μg/ml in combination with fMLP at the concentration 20μg / ml exhibited synergistic effect on tumor cells in the presence of macrophages（CDI〈0.75）, fMLP inhibited the growth of colon carcinoma 26 by 50.0% when it at dose of 1 mg/mouse was administered peritumorally. BAM （1 mg/kg, intraperitoneally, three times） alone and BAM - fMLP combination inhibited the growth of colon carcinoma 26 by 38.6% and 78.4%, respectively （CDI=0.71） on day 12. The amount of O2 ·^- released from fMLP 4.6×10^-7 mol/L （0.2μg/ml） stimulated macrophages which were treated by BAM in vitro increased significantly（P〈0.01）, fMLP 2.3×10^-6 mol/L （1μg/ml） could not stimulate macrophages to release NO, but may stimulate macrophages treated with BAM 10μg/ml and 100μg/ml to release NO significantly（P〈0.01）. Conclusion： The inhibitory action of fMLP-boanmycin combination on the growth of mouse colon carcinoma have synergism, which may associate with the increase of O2 ·^- and NO released by macrophages. Chemotactic modulation in combination with chemotherapy may be a novel regimen in the treatment of cancer.

关键词： Chemotactic peptide fMLP Boanmycin Colon carcinoma

Mutual Neutralization of Na^(+)/O^(-) Ions in Slow Collisions

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Chinese Physics Letters 1996年第2期13卷 93-96页

作者： ZHOU Xiao-xin dong Chen-zhong Department of Physics Northwest Normal UniversityLanzhou 730070

The mutual neutralization cross sections of Na^(+)/O^(-) ions at low energy have been calculated by using the multichannel LandaZener *** asymptotic method is used for estimating tBe coupling matrix elements between tbe ionic and covalent states at the crossing points of diabatic potential *** results of calculation are compared with available experimental data.

关键词： theory. mutual asymptotic

Thickening-upward cycles in deep-marine and deep-lacustrine turbidite lobes:examples from the Clare Basin and the Ordos Basin

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Journal of Palaeogeography 2020年第2期9卷 216-231页

作者： Lei-Fu Zhang Da-zhong dong PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China School of Geological Sciences University College DublinDublin 4Ireland National Energy Shale Gas Research(Experiment)Center Langfang 065CX)7Hebei ProvinceChina CNPC Key Laboratory of Unconventional Oil and Gas Langfang 065007Hebei ProvinceChina

Deep-marine and deep-lacustrine reservoirs have been targets for conventional and unconventional oil and gas exploration and development for decades. Thickening-upward cycles in the deep-marine Carboniferous Ross Sandstone Formation outcrops in western Ireland and the deep-lacustrine Triassic Yanchang Formation outcrops in southeast Ordos Basin have been investigated and correlated in this study. Typical thickening-upward cycles consisting of, from bottom to top:(1) laminated shales/shales with interbedded siltstone beds;(2) interbedded sandstones/siltstones and mudstones;(3) structureless massive sandstones, are well recognized in these outcrops and are interpreted as turbidite lobes. A continuously prograding lobe-element model is proposed to explain the repeated stacking of thickening-upward cycles. Thickening-upward cycles developed within deep-marine and deeplacustrine environments are highly comparable in many aspects, such as sedimentary structures, sheet-like geometries and amalgamation features. A frequent and strong degree of amalgamation is developed within the massive sandstone at the top of each thickening-upward cycle, suggesting a layer-by-layer depositional *** observations and comparison with deep-marine counterparts support the occurrence of turbidity flows in the Yanchang Formation, Ordos Basin.

关键词： Thickening-upward cycle Deep-marine turbidite Deep-lacustrine turbidite Yangchang Formation Ordos Basin Kilbaha Bay

Effects of Vegetation Succession on Soil Fertility Within Farming-Plantation Ecotone in Ziwuling Mountains of the Loess Plateau in China

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Agricultural Sciences in China 2010年第10期9卷 1481-1491页

作者： LIANG Jian WANG Xiao-an YU zhong-dong dong zhong-min WANG Jin-cheng School of Life Sciences Shaanxi Normal University Xi'an 710062 P.R.China College of Forestry Northwest A&F University Yangling 712100 P.R. China Department of Biology Saint Mary 's University Halifax B3H 3C3 Canada

To further understand the relationship between vegetation succession and soil fertility within farming-plantation ecotone in Ziwuling Mountains of the Loess Plateau, nine kinds of widely distributed communities at different succession stages were selected, and the effects of vegetation succession on soil fertility were studied through the methods of comparing two hierarchical clustering （similarity index： B） and other multivariate analysis. The results showed that：（i） the similarity in clustering pattern of nine communities which classified by plant species and soil nutrients respectively showed a trend of B ^-overall plant-soil0-10cn〉B^-overall plant-soil 10-20 cm 〉B^- overall plant-soil 20-40 cm, and for the top soil, it showed a trend of B^- grass-soil 0-10 cm 〉 B^-shrub-soil 0-10 cm 〉 Btree-soil0-10 cm; （ii） soil fertility increased during the succession process from abandoned land to forest community, and the soil fertility of forest community showed an increased order of coniferous forest →mixed forest →broadleaf forest; （iii） during the process of vegetation succession, the variation of topsoil fertility was higher than that of the subsurface soil （coefficient of variation： CV0-10 cm 〉CV 10-20 cm 〉 CV20-40 cm）, and when the succession developed into the stages of shrub and forest communities, the top soil fertility had been improved significantly; and （iv） for the subsurface soil of the communities at the advanced succession stages, the soil fertility also increased to some extent. Our results suggested that the method of comparing two hierarchical clustering reflected the similarity level of different cluster patterns, therefore, it was helpful to study the relationship between vegetation succession and soil fertility. There was a corresponding relationship between the change process of soil fertility from the top soil to subsurface soil and the process of vegetation succession from the early stages to the advanced stage. The differentiations of soil fertil

关键词： vegetation succession soil fertility vegetation-soil communities multivariate statistical analysis LoessPlateau

Control of cotton pests and diseases by intercropping:A review

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Journal of Integrative Agriculture 2021年第12期20卷 3089-3100页

作者： CHI Bao-jie ZHANG dong-mei dong He-zhong Cotton Research Center Shandong Academy of Agricultural SciencesJinan 250100P.R.China College of Life Sciences Shandong Normal UniversityJinan 250014P.R.China College of Agronomy Hebei Agricultural UniversityBaoding 071000P.R.China

Cotton(Gossypium hirsutum L.)is a globally important crop that is often damaged by pests and *** cotton pests and diseases management is dependent on chemical *** chemical pesticides are usually effective,long-term application of these pesticides often leads to increased insecticide resistance in the pests,fewer natural enemies,reduced natural control,and a degraded *** of increased environmental awareness and the need for sustainable cotton production,the control of cotton pests and diseases using biological means like intercropping is increasingly receiving *** of cotton with other crops can often boost the total yield and output of the intercropping system and provide significant economic benefits without sacrificing cotton *** also increases the number of natural enemies,and reduces the occurrence of cotton pests and diseases by altering the ecological structure and environmental conditions in the ***-based intercropping is an effective strategy to reduce the competition between cotton and grain or other economic crops for arable *** is also an important way to increase the populations of natural enemies in cotton fields for the management of pests and ***,inappropriate intercropping can also increase labor requirements and even result in inadequate control of pests and *** review focuses on the performance and the mechanisms of intercropping for reducing cotton pests and disease as well as on the effective management of intercropping *** risks and limitations,as well as the study approaches needed and the prospects of intercropping for the control of cotton pests and diseases,are also *** information is intended to aid researchers and growers in designing economically viable and ecologically friendly pest and disease management strategies that will reduce the use of chemicals and the cost of cotton production.

关键词： cotton-based intercropping pest management risk and limitation