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聚氨酯包膜型缓释肥对婺城地区双季稻产量及化肥利用率的影响

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浙江农业科学 2024年第3期65卷 521-524页

作者：蒋敏华丁懿李宽孟浩然潘奕旻张超金华市婺城区植物保护和耕肥管理站浙江金华321025

依托测土配方技术,根据土壤供肥能力、水稻需肥规律及目标产量等,采取以土定产、以产定肥、施用缓释肥等原则,在制定科学合理的施肥方案基础上,探究聚氨酯包膜型缓释肥对婺城地区双季稻产量及化肥利用率的影响。试验结果显示,早稻全肥... 详细信息

依托测土配方技术,根据土壤供肥能力、水稻需肥规律及目标产量等,采取以土定产、以产定肥、施用缓释肥等原则,在制定科学合理的施肥方案基础上,探究聚氨酯包膜型缓释肥对婺城地区双季稻产量及化肥利用率的影响。试验结果显示,早稻全肥处理目标产量为6000.0 kg·hm^(-2),实际产量为6405.0 kg·hm^(-2),化肥利用率分别为氮44.9%、磷25.2%、钾49.1%;晚稻全肥处理目标产量为8250.0 kg·hm^(-2),实际产量为8707.5 kg·hm^(-2),化肥利用率分别为氮43.6%、磷27.8%、钾51.6%。聚氨酯包膜型缓释肥是一种优良的缓释肥,施用聚氨酯包膜型缓释肥双季稻氮磷钾平均利用率分别达44.3%、26.5%和50.4%,建议施用聚氨酯包膜型缓释肥替代普通复合肥。

关键词：双季稻缓释肥化肥利用率

有机缓释肥施用化肥减量减次对婺城地区晚稻产量的影响

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浙江农业科学 2024年第2期65卷 258-261页

作者：蒋敏华丁懿孟浩然李宽张超潘奕旻金华市婺城区植物保护和耕肥管理站浙江金华321025

本试验在常规施肥的基础上,通过施用有机缓释肥进行等氮、减氮及减少施用次数试验,探究有机缓释肥减量减次对婺城地区晚稻生产的影响。试验结果显示,与常规处理相比,有机等氮处理晚稻增产显著,有机减N 20%处理晚稻小幅增产,而有机减N 20... 详细信息

本试验在常规施肥的基础上,通过施用有机缓释肥进行等氮、减氮及减少施用次数试验,探究有机缓释肥减量减次对婺城地区晚稻生产的影响。试验结果显示,与常规处理相比,有机等氮处理晚稻增产显著,有机减N 20%处理晚稻小幅增产,而有机减N 20%不追处理晚稻产量略有下降,有机减N 40%处理晚稻产量则出现大幅降低。有机缓释肥是一种优良的缓释肥,对于婺城区水稻种植,可施用有机缓释肥替代普通平衡型复合肥,施用方式为一基一追,可比常规施肥减少一次追肥,达到省时省工的目的,也可适当减少肥料投入,达到减量增效的目的。另外,施用有机缓释肥也可采用一次性基施施肥方式,此方式不建议减肥,同时应及时关注水稻长势,如果水稻后期出现脱肥现象,应及时追肥。

关键词：婺城晚稻有机缓释肥产量

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Effective Increase of Crystal Area during Sublimation Growth of 6H-SiC by Using the Cone-shaped Baffle

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Journal of Materials Science & Technology 2007年第5期23卷 685-688页

作者： Shouzhen jiang Xiangang XU Xiaobo HU Juan LI Xiufang CHEN minhua jiang State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China College of Physics and Electronics Shandong Normal University Jinan 250014 China

A novel design of crucible is proposed in this paper for the growth of SiC crystals. The relation between grown crystal shape and temperature distribution in a growth chamber was discussed. It is pointed out that the crystal shape had a close relationship with temperature distribution. The calculations suggested that the radial temperature field of the growing crystal became homogenous by setting up the cone-shaped baffle in the growth chamber. By modifying the crucible design and temperature distribution in the growth chamber, it is possible to enhance the enlargement of crystal, and also possible to keep grown surface flat.

关键词： 6H-SIC Sublimation method Simulation Temperature distribution

Hydrochloric Acid-Promoted Synthesis of cBN via Hydrothermal Route

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Journal of Materials Science & Technology 2007年第6期23卷 768-770页

作者： Haihui jiang Kai LI Ligang GAI Qilong WANG Deliang CUI minhua jiang State Key Lab of Crystal Materials Shandong University Jinan 250100 China School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China School of Chemical Engineering Shandong Institute of Light Industry Jinan 250353 China

Single phase crystalline cubic boron nitride （cBN） with high yield was prepared by hydrothermal route at low temperature, using hydrochloric acid （HCI） as the promoter. The promotion effect of HCI on the synthesis... 详细信息

关键词： Hydrochloric acid-promoted Cubic boron nitride Hydrothermal route

Synthesis of High Purity SiC Powder for High-resistivity SiC Single Crystals Growth

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Journal of Materials Science & Technology 2007年第1期23卷 118-122页

作者： Li WANG Xiaobu HU Xiangang XU Shouzheng jiang Lina NING minhua jiang State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

High purity silicon carbide （SIC） powder was synthesized in-situ by chemical reaction between silicon and carbon powder. In order to ensure that the impurity concentration of the resulting SiC powder is suitable for high-resistivity SiC single crystal growth, the preparation technology of SiC powder is different from that of SiC ceramic. The influence of the shape and size of carbon particles on the morphology and phase composition of the obtained SiC powder were discussed. The phase composition and morphology of the products were investigated by X-ray diffraction, Raman microspectroscopy and scanning electron microscopy. The results show that the composition of resulting SiC by in-situ synthesis from Si/C mixture strongly depends on the nature of the carbon source, which corresponds to the particle size and shape, as well as the preparation temperature. In the experimental conditions, flake graphite is more suitable for the synthesis of SiC powder than activated carbon because of its relatively smaller particle size and flake shape, which make the conversion more complete. The major phase composition of the full conversion products is β-SiC, with traces of α-SiC. Glow discharge mass spectroscopy measurements indicated that SiC powder synthesized with this chemical reaction method can meet the purity demand for the growth of high-resistivity SiC single crystals.

关键词： Activated carbon Flaky graphite Particle size SiC powder High purity

Investigation of the 6H-SiC (0001) surface by AFM

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Journal of University of Science and Technology Beijing 2008年第5期15卷 654-658页

作者： Shouzhen jiang Guangwei Yu Yingmin Wang Xiaobo Hu Xiangang Xu minhua jiang State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China College of Physics and Electronics Shandong Normal University Jinan 250014 China

Micropipe and step structures on 6H-SiC （0001） surface were investigated by an atomic force microscopy （AFM）. On the facet,all micropipes examined are the origins of spiral steps,indicating that dislocations intersect the surface at these points. Micropipes are empty-core super-dislocations as originally described by Frank. The micropipe radius increases with the square of the dislocation Burgers vector. From the center to the periphery,step structures change with different surface inclinations. Regular step is observed within the central faceted area. Step bunching and atomically rough surfaces are observed within the peripheral convex area. If the inclination with respect to the （0001） plane is large enough,step bunching of 15R-SiC can be observed.

关键词： atomic force microscopy micropipes step bunching polytypes

A NEW NONLINEAR OPTICAL MATERIAL-ORGANOMETALLIC COMPLEX TRIALLYLTHIOUREA MERCURY CHLORIDE

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Chinese Physics Letters 1990年第7期7卷 334-336页

作者： YUAN Duorong ZHANG Nan TAO Xutang XU Dong jiang minhua Institute of Crystal Materials Shandong UniversityJinan 250100

Tri-allylthiourea mercury chloride(ATMC),an organometallic complex,is a new nonlinear optical material with high second harmonic generation(SHG)*** SHG effect of ATMC is three times as large as that of urea *** single crystal of 15×15×10mm^(3) has been *** studies of crystal growth,structure,and general properties have been carried *** results show that organometallic complexes are promising nonlinear optical materials for wide applications.

关键词： effect crystal nonlinear

Fine Machining of Large-Diameter 6H-SiC Wafers

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Journal of Materials Science & Technology 2006年第5期22卷 681-684页

作者： Xiufang CHEN Juan LI Deying MA Xiaobo HU Xiangang XU minhua jiang State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

Three main machining processes of large-diameter 6H-SiC wafers were introduced in this paper. These processes include cutting, lapping and polishing. Lapping causes great residual stresses and deep damage layer which can be reduced gradually with subsequent polishing processes. Surfaces prepared by mechanical polishing （MP） appeared a large number of scratches with depth of 5-8 nm. These scratches can be effectively removed by chemo-mechanical polishing （CMP）. After CMP. extremely smooth and low damage layer surface with roughness Ra=0.3 nm was obtained. Atomic force microscopy （AFM） and optical microscopy were used to observe the surface morphology of samples and a high resolution X-ray diffractometer （HRXRD） was used for the crystal lattice perfection of the subsurface region. Changes of surface residual stresses during machining processes were investigated by HRXRD.

关键词： 6H-SiC Chemo-mechanical polishing (CMP) Roughness

2H-SiC Dendritic Nanocrystals In Situ Formation from Amorphous Silicon Carbide under Electron Beam Irradiation

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Journal of Rare Earths 2006年第Z1期24卷 54-55页

作者： Li Xianxiang Hu Xiaobo jiang Shouzheng Dong Jie Xu Xiangang jiang minhua State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

Under electron beam irradiation,the in-situ formation of 2H-SiC dentritic nanocrystals from amorphous silicon carbide at room temperature was *** homogenous transition mainly occurs at the thin edge and on the surface of specimen where the energy obtained from electron beam irradiation is high enough to cause the amorphous crystallizing into 2H-SiC.

关键词： electron beam irradiation 2H-SiC dendritic nanocrystal amorphous silicon carbide