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干湿交替灌溉与植物生长调节剂对水稻光合特性及内源激素的影响

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作物学报 2025年第1期51卷 174-188页

作者：赵黎明段绍彪项洪涛郑殿峰冯乃杰沈雪峰广东海洋大学滨海农业学院广东湛江524088 黑龙江省农业机械工程科学研究院绥化分院黑龙江绥化152054

为探明干湿交替灌溉与植物生长调节剂(plant growth regulators, PGRs)对水稻光合特性、内源激素及产量的影响。采用盆栽与大田相结合方式,以龙粳31为试验材料,设置轻干湿交替灌溉(MI)和重干湿交替灌溉(HI)2种灌溉处理,于分蘖盛期和剑... 详细信息

为探明干湿交替灌溉与植物生长调节剂(plant growth regulators, PGRs)对水稻光合特性、内源激素及产量的影响。采用盆栽与大田相结合方式,以龙粳31为试验材料,设置轻干湿交替灌溉(MI)和重干湿交替灌溉(HI)2种灌溉处理,于分蘖盛期和剑叶展叶期喷施已酸二乙氨基乙醇酯(diethylaminoethylcaproate,DA)、6-苄氨基腺嘌呤(6-benzylaminoadenine,BA)和BA(分蘖盛期)+DA(剑叶展叶期)3种PGRs,并设置清水对照,探究干湿交替灌溉、PGRs及互作下干物质积累、光合特性、内源激素及产量差异。结果表明,与HI相比, MI显著增加了抽穗后叶面积、叶面积指数、SPAD值及净光合速率,提高了剑叶与籽粒IAA、GA3和ZR含量,降低了ABA含量,增加了干物质积累及茎鞘物质转运能力,并在改善节间性状基础上增加了结实率、每穗粒数及粒重,增产5.30%(盆栽)和5.11%(大田)。与CK相比,喷施BA+DA显著提高了抽穗后剑叶净光合速率、干物质积累及茎鞘物质转运能力,提高了剑叶与籽粒IAA、GA3和ZR含量,增加了千粒重、结实率、收获指数、每穗粒数和粒重,增产6.60%(盆栽)和6.05%(大田),其次是BA。干湿交替灌溉与PGRs互作对叶面积指数、内源激素含量、每穗粒数及千粒重存在显著影响,其中MI×(BA+DA)处理更有助于维持抽穗后绿叶功能持续期,提高叶片SPAD值、叶面积、叶面积指数和净光合速率,增强干物质积累及茎鞘物质转运能力,提高叶片与籽粒IAA、GA3和ZR含量,促进同化物向籽粒输出,并在稳定穗数基础上增加了千粒重、每穗粒数和粒重,提高了结实率和收获指数,实现产量较其他处理及CK增幅3.17%~12.57%(盆栽)和3.14%~11.55%(大田),而HI×(BA+DA)处理可实现MI×CK产量效果。综上所述,干湿交替灌溉配合喷施BA+DA可作为本区域水稻高产高效生产环节中的一种节水化控栽培组合措施。

关键词：水稻干湿交替灌溉植物生长调节剂光合特性内源激素产量

Engineering yolk-shell CuCo_(2)S_(4)@Cu_(2)O Z-scheme nanoreactors for accelerating generation of value-added chemicals and of degradation multi-organic contaminants

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Journal of Materials Science & Technology 2023年第25期156卷 54-63页

作者： xue feng Lei Zhang College of Chemistry Liaoning University66 Chongshan Middle RoadShenyang 110036China

The synthesis of solar-driven chemical value-added products and the degradation of pollutants is a promising approach for sustainable development. However, achieving these works via photocatalysts with efficient charge-separation, photo-absorption is challenging. A yolk-shell CuCo_(2)S_(4)@Cu_(2)O Z-scheme nanoreactor (YS-CuCo_(2)S_(4)@Cu_(2) O-NR) with octahedron Cu_(2)O as the core and tubular CuCo2 S4 as the shell, has been synthesized by regulating composition and morphology. YS-CuCo_(2)S_(4)@Cu_(2)O-NR shows superior photocatalytic activities for producing H_(2) O_(2) collaborates by selective oxidation of benzyl alcohol (BA) to high value-added benzaldehyde (BAD)/utilized Fenton-like reaction to degrade multi-pollutants through space-confinement effect, reaching 80% conversion and 99% selectivity of BA, a yield of 12 mM g^(−1) for H_(2)O_(2) and above 90% degradation efficiency for multi-pollutants. A photocatalysis nanoconfinement reactor system is proposed and demonstrated by using yolk-shell to enhance the performance of the chemical reaction. Mechanism studies show that the yolk-shell provides confined space to accelerate redox reaction kinetics;while the inner void promotes light harvesting and keeps yolk Cu_(2) O from deactivation;combined with the Z-scheme charge transfer, engineering Cu^(+) /Cu^(2+) active composition, they are favorable for enhancing the H_(2) O_(2) generation and Fenton-like activity. These findings provide new opportunities for application of yolk-shell Z-scheme metal-oxide-based photocatalysts.

关键词： Octahedron yolk-shell structure catalyzer Z-scheme charge transfer H2O_(2)generation Selective oxidation of BA Fenton-like reaction

Ghost Length, Cone Length and Complete Level of DG Modules

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1279-1310页

作者： xue feng MAO Department of Mathematics Shanghai University

In this paper, we introduce a new numerical invariant complete level for a DG module over a local chain DG algebra and give a characterization of it in terms of ghost length. We also study some of its upper bounds. The cone length of a DG module is an invariaut closely related with the invariant level. We discover some important results on it.

关键词： Local chain DG algebra DG module ghost length cone length complete level

The Ext-Group of Unitary Equivalence Classes of Unital Extensions

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2329-2342页

作者： Yi feng xue Department of Mathematics East China Normal University Shanghai 200241 P. R. China

Let A be a unital separable nuclear C＊-algebra which belongs to the bootstrap category N and B be a separable stable C＊-algebra. In this paper, we consider the group Ext,（A, B） consisting of the unitary equivalence classes of unital extensions T： A→ Q（B）. The relation between Ext,（A, B） and Ext（A, B） is established. Using this relation, we show the half-exactness of Ext,（-, B） and the （UCT） for Ext,（A, B）. Furthermore, under certain conditions, we obtain the half-exactness and Bott periodicity of Extu （A, .）.

关键词： Unital extension multiplier algebra Ext-group quasi-unital ,-homomorphism

EFFECT OF TUNGSTEN ADDITION ON MECHANICAL PROPERTIES OF Fe_3Al-BASED ALLOYS

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中国有色金属学会会刊：英文版 1999年第2期9卷 88-92页

作者： feng, xue Yangshan, Sun Southeast Univ Nanjing China

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１ＩＮＴＲＯＤＵＣＴＩＯＮＩｒｏｎａｌｕｍｉｎｉｄｅｓｂａｓｅｄｏｎＦｅ３Ａｌｏｆｅｒｅｘｃｅｌｌｅｎｔｏｘｉｄａｔｉｏｎａｎｄｓｕｌｆｉｄａｔｉｏｎｒｅｓｉｓｔａｎｃｅ，ｗｉｔｈａｌｏｗｅｒｍａｔｅｒｉａｌｃｏｓｔａｎｄｄｅｎｓｉｔｙｔｈａｎｓｔ...

关键词： Fe3AlWmechanical properties

Anomalous Western Pacific Subtropical High during Late Summer in Weak La Nia Years: Contrast between 1981 and 2013

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Advances in Atmospheric Sciences 2016年第12期33卷 1351-1360页

作者： feng xue Fangxing FAN International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029

Both 1981 and 2013 were weak La Nifia years with a similar sea surface temperature （SST） anomaly in the tropical Pacific, yet the westem Pacific subtropical high （WPSH） during August exhibited an opposite anomaly in the two years. A comparison indicates that, in the absence of a strong SST anomaly in the tropics, the cold advection from Eurasian high latitudes and the convection of the western Pacific warm pool play important roles in influencing the strength and position of the WPSH in August. In August 1981, the spatial pattern of 500 hPa geopotential height was characterized by a meridional circulation with a strong ridge in the Ural Mountains and a deep trough in Siberia, which provided favorable conditions for cold air invading into the lower latitudes. Accordingly, the geopotential height to the north of the WPSH was reduced by the cold advection anomaly from high latitudes, resulting in an eastward retreat of the WPSH. Moreover, an anomalous cyclonic circulation in the subtropical western Pacific, excited by enhanced warm pool convection, also contributed to the eastward retreat of the WPSH. By contrast, the influence from high latitudes was relatively weak in August 2013 due to a zonal circulation pattern over Eurasia, and the anomalous anticyclonic circulation induced by suppressed warm pool convection also facilitated the westward extension of the WPSH. Therefore, the combined effects of the high latitude and tropical circulations may contribute a persistent anomaly of the WPSH in late summer, despite the tropical SST anomaly being weak.

关键词： western Pacific subtropical high late summer tropical circulation high latitude circulation warm pool convection

Phase Transition of the Pacific Decadal Oscillation and Decadal Variation of the East Asian Summer Monsoon in the 20th Century

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Advances in Atmospheric Sciences 2016年第3期33卷 330-338页

作者： Xiao DONG feng xue International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences

This paper focuses on the relationship between the phase transition of the Pacific decadal oscillation （PDO） and decadal variation of the East Asian summer monsoon （EASM） in the twentieth century. The first transition occurred in the 1940s, with an enhanced SST in the North Pacific and reduced SST in the tropical eastern Pacific and South Indian Ocean. In agreement with these SST changes, a higher SLP was found in most parts of the Pacific, while a lower SLP was found in the North Pacific and most parts of the Indian Ocean. In this case, the EASM was largely enhanced with a southerly anomaly in the lower troposphere along the east coast of China. Correspondingly, there was less rainfall in the Yangtze River valley and more rainfall in northern and southern China. An opposite change was found when the PDO reversed its phase in the late 1970s. In the tropical Indian Ocean and western Pacific, however, the SST was enhanced in both the 1940s and 1970s. As a result, the western Pacific subtropical high （WPSH） tended to extend westward with a larger magnitude in the 1970s. The major features were reasonably reproduced by an atmospheric general circulation model （IAP AGCM4.0） prescribed with observed SST and sea ice. On the other hand, the westward extension of the WPSH was exaggerated in the 1970s, while it was underestimated in the 1940s. Besides, the spatial pattern of the simulated summer rainfall in eastern China tended to shift southward compared with the observation.

关键词： Pacific decadal oscillation East Asian summer monsoon western Pacific subtropical high IAP AGCM4.0

Microstructure of ferrospheres in fly ashes: SEM, EDX and ESEM analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1595-1600页

作者： Qing-feng xue Sheng-gao LU Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition College of Environmental and Resource Sciences Zhejiang University Hangzhou 310027 China

Ferrospheres in fly ashes from a coal-fired power plant were extracted by a magnetic separation technique and their microstructure was studied by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and environmental scanning electron microscopy (ESEM). Ferrospheres in fly ashes show significant iron enrichment compared to their respective fly ashes. Iron oxides in ferrospheres mainly occur as minerals magnetite (Fe3O4) and hematite (α-Fe2O3), which are derived mainly from the decomposition and oxidation of iron-bearing minerals in coal during combustion. EDX data indicate that ferrospheres also contain Si, S, Al and Ca resulting from quartz, mullite, anhydrite and amorphous materials. A large percentage of ferrospheres are commonly 5～50 μm in size. The microstructure of ferrospheres includes smooth, polygonal, dendritic, granular and molten drop characteristics. SEM coupled with EDX provided fast and accurate results of the microstructure and chemical composition of ferrospheres, and helped us to assess environmental issues related to the disposal and utilization of fly ashes.

关键词： Fly ash Ferrosphere Microstructure Scanning electron microscopy (SEM)

Sample Generation for Security Region Boundary Identification Based on Topological Features of Historical Operation Data

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1087-1095页

作者： Xiaokang Wu Wei Xu feng xue College of Energy and Electrical Engineering Hohai UniversityNanjingChina NARI Group Corporation NanjingChina State Grid Electric Power Research Institute NanjingChina

Since the scale and uncertainty of the power system have been rapidly increasing,the computation efficiency of constructing the security region boundary(SRB)has become a prominent *** on the topological features of historical operation data,a sample generation method for SRB identification is proposed to generate evenly distributed samples,which cover dominant security *** boundary sample pair(BSP)composed of a secure sample and an unsecure sample is defined to describe the feature of *** resolution,sampling,and span indices are designed to evaluate the coverage degree of existing BSPs on the SRB and generate samples closer to the *** on the feature of flat distribution of BSPs over the SRB,the principal component analysis(PCA)is adopted to calculate the tangent vectors and normal vectors of ***,the sample distribution can be expanded along the tangent vector and corrected along the normal vector to cover different security ***,a sample set is randomly gen-erated based on the IEEE standard example and another new sample set is generated by the proposed *** results indicate that the new sample set is closer to the SRB and covers different security modes with a small calculation time cost.

关键词： Clustering analysis principal component analysis(PCA) sample generation security region boundary(SRB)