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水稻氧力粉包膜直播技术
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作者 李维华 《四川气象》 1997年第3期49-50,共2页
达川地区是农业大区,农业生产长期沿用传统耕作方法,其生产力较低,水稻采用氧力粉包膜直播法,不仅利于机械化操作,减轻劳动强度,而且由于氧力粉的效用,使之苗齐、苗壮,根系发达,有效稳多,从而达到稳产高产的目的。
关键词 水稻 包膜 直播 生育特征 播种
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小麦粉面包烘烤品质指标的研究 Ⅰ.逐步回归分析筛选关键性指标 被引量:4
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作者 赵友梅 许自成 《河南工业大学学报(自然科学版)》 CAS 1989年第2期80-87,共8页
本实验应用逐步回归方法研究了河南50个小麦品种(系)的面包烘烤品质各指标间的关系,结果表明:面包评分、体积和比容均是评价面包品质优劣的综合性指标。和体积,比容相比较,以面包评分和烘烤品质各指标建立的回归方程具有更高的F值,复相... 本实验应用逐步回归方法研究了河南50个小麦品种(系)的面包烘烤品质各指标间的关系,结果表明:面包评分、体积和比容均是评价面包品质优劣的综合性指标。和体积,比容相比较,以面包评分和烘烤品质各指标建立的回归方程具有更高的F值,复相关系数也较高。用面包评分代表面包烘烤品质可能较体积和比容更可靠更稳定。面包评分可看作是评价值和粉力二者综合作用的结果。 展开更多
关键词 逐步回归 评分 体积 比容 评价值 粉力 沉淀值 高分子量麦谷蛋白亚基组成得分
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高强力再生胶粉在全钢载重子午线轮胎胎侧胶中的应用
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作者 单振 刘强 +1 位作者 周丽君 吴霞 《橡胶科技》 2015年第3期31-34,共4页
研究高强力再生胶粉在全钢载重子午线轮胎胎侧胶中的应用。结果表明,添加5份高强力再生胶粉对全钢载重子午线轮胎胎侧胶的性能无不良影响,且能降低轮胎的生产成本。
关键词 高强再生胶 全钢载重子午线轮胎 胎侧胶
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明胶粉喷雾干燥工艺的研究 被引量:1
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作者 张业聪 付丽红 《中国皮革》 CAS 北大核心 2008年第5期6-9,17,共5页
利用正交试验的极差分析法,对明胶粉喷雾干燥工艺进行了研究。以明胶液浓度、进料量、进口温度和抽风量作为考察因素,以明胶粉冻力、黏度、得率及水分作为考察指标,优选出最佳喷雾干燥条件。结果表明,各因素对明胶粉冻力的影响次序... 利用正交试验的极差分析法,对明胶粉喷雾干燥工艺进行了研究。以明胶液浓度、进料量、进口温度和抽风量作为考察因素,以明胶粉冻力、黏度、得率及水分作为考察指标,优选出最佳喷雾干燥条件。结果表明,各因素对明胶粉冻力的影响次序为:进料量〉明胶液浓度〉抽风量〉进口温度;对明胶粉黏度的影响次序为:抽风量〉进料量〉明胶液浓度〉进口温度,对明胶粉得率和水分的影响次序均为:明胶液浓度〉进料量〉抽风量〉进口温度。最佳工艺条件:明胶液浓度5%~6%、进料量18mL/min、进口温度170—175℃、抽风量35~37m^3/h。 展开更多
关键词 喷雾干燥 明胶 黏度 水分 得率
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Properties of Self-recoverable Mechanoluminescence Phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) and Its Information Encryption Application
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作者 ZHANG Ting WANG Zhijun +3 位作者 WANG Dawei ZHAO Jinxin YANG Zhiping LI Panlai 《发光学报》 EI CAS CSCD 北大核心 2024年第9期1445-1455,共11页
A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)... A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)∶Eu^(3+)can produce red mechanoluminescence,and importantly,it shows good repeatability.The mechanoluminescence of Ca_(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge carriers stored in the traps,which can be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment tests.The mechanoluminescence color can be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter writing.The encryption scheme for secure communication was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption performance.The results suggest that the mechanoluminescence phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optical information encryption. 展开更多
关键词 PHOSPHOR MECHANOLUMINESCENCE self-recoverable information encryption
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基板晶体学特征对镀层相结构及抗粉化性能的影响
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作者 邓永刚 潘恩宝 +1 位作者 李云龙 邸洪双 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2018年第8期1127-1131,1136,共6页
为了改善合金化镀锌板镀层的抗粉化性能,研究了基板晶体学特征对合金化镀层相结构及抗粉化性能的影响.结果表明:γ织构增加基板成型性的同时抑制镀层内裂纹源的萌生;板面织构(111)-(113)-(313)//RP(轧面)在镀锌过程中,抑制ζ相的生成,... 为了改善合金化镀锌板镀层的抗粉化性能,研究了基板晶体学特征对合金化镀层相结构及抗粉化性能的影响.结果表明:γ织构增加基板成型性的同时抑制镀层内裂纹源的萌生;板面织构(111)-(113)-(313)//RP(轧面)在镀锌过程中,抑制ζ相的生成,促进δ相的生成;板面织构(001)-(101)//RP促进ζ相的生成.在合金化退火过程中镀锌板ζ相转变为δ相,最后变为Γ相,导致镀层内产生不同相结构,进而影响镀层的抗粉化性能和与基板之间的黏附力.此外,增加基板上{113}〈110〉体积分数与{111}〈110〉体积分数的比值,更有利于镀层内非基面织构的生成,增加合金化镀层的塑性.另外,基板表面的大、小角度晶界的体积分数也是影响镀层相结构的主要因素. 展开更多
关键词 合金化镀锌层 晶体学特征 化抗 镀层相结构
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面粉流变特性汇总表
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《河南农业》 1995年第6期36-36,共1页
关键词 流变特性 样品 吸水率 峰值时间 稳定时间 延伸性 抗延性 粉力
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Influence of the boundary effect on the mechanical response test of pavement cushion under the wetting effect of silt
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作者 Luo Qiqi Yu Qian +3 位作者 Zhang Sheng Ma Xinyan Ye Xinyu Du Yinfei 《Journal of Southeast University(English Edition)》 EI CAS 2024年第3期266-274,共9页
Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the... Through a self-developed model test system,the mechanical properties of silt and the deformation characteristics of airport runways were investigated during the period of subgrade wetting.Based on the test results,the reliability of the numerical simulation results was verified.Numerical models with different sizes were established.Under the same cushion parameter and loading width ranges,the effects of the cushion parameters and loading conditions on the mechanical responses of the cushion before and after subgrade wetting were analyzed.The results show that the internal friction angles of silt with different wetting degrees are approximately 34°.The cohesion is from 8 to 44 kPa,and the elastic modulus is from 15 to 34 MPa.Before and after subgrade wetting,the variation rates of the cushion horizontal tensile stresses with the same cushion parameters and loading width ranges are different under the influence of boundary effects.After subgrade wetting,the difference in the variation rates of the cushion horizontal tensile stresses under the same cushion parameter range decreases compared with that before subgrade wetting;however,this difference increases under the same loading width range.Before and after subgrade wetting,the influence of the boundary effect on the mechanical response evaluation of the cushion is not beneficial for optimizing the pavement design parameters.When the cushion thickness is more than 0.25 m,the influence of the boundary effect can be disregarded. 展开更多
关键词 pavement cushion silt subgrade WETTING boundary effect mechanical response
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Vitality and storage condition of Syringa pollen 被引量:6
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作者 周莉 罗凤霞 +1 位作者 代力民 张惠华 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期67-70,共4页
The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The result... The fresh pollen vitality, the effect of different storage conditions on the pollen vitality, and the difference of vitality among the species of seven species of Syringa were determined in Shenyang, China. The results indicated that the pollen vi-tality (81.5%) of Syringa villosa was the highest among the seven tested species, followed by S. microphylla and S. meyeri, and that of S. oblata var. affinis was the lowest. The low temperature was the best condition for storage of pollen of Syringa, and the most proper temperature for the storage was 0-2 癈. The storability of S. microphylla was the best of all, and it could be stored over 60 days at the temperature of 0-2 癈, next was S. villosa and S. meyeri. 展开更多
关键词 SYRINGA POLLEN VITALITY Storage condition
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Kinetics of SiO_2 leaching from Al_2O_3 extracted slag of fly ash with sodium hydroxide solution 被引量:12
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作者 王若超 翟玉春 +1 位作者 宁志强 马培华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1928-1936,共9页
Kinetics of SiO2 leaching from Al2O3 extracted slag of fly ash with sodium hydroxide solution was studied.The effect of leaching temperature,mass ratio of NaOH to SiO2 and stirring speed on SiO2 leaching rate was inve... Kinetics of SiO2 leaching from Al2O3 extracted slag of fly ash with sodium hydroxide solution was studied.The effect of leaching temperature,mass ratio of NaOH to SiO2 and stirring speed on SiO2 leaching rate was investigated.The results show that increasing leaching temperature,mass ratio of NaOH to SiO2 and stirring speed increases SiO2 leaching rate.The SiO2 leaching rate is 95.66%under the optimized conditions.There are two stages for the SiO2 leaching process,and the leaching reaction is very rapid in the first stage but quite slow in the second stage.The whole leaching process follows the shrinking core model,and the outer diffusion of no product layer is the rate-controlling step.The activation energies of the first and second stages are calculated to be8.492 kJ/mol and 8.668 kJ/mol,respectively.The kinetic equations of the first and the second stages were obtained,respectively. 展开更多
关键词 fly ash LEACHING KINETICS SIO2
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Study on the Flowering Biological Characteristics of Prunus domestica × armeniaca 被引量:1
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作者 魏雅君 李雯雯 +5 位作者 冯贝贝 徐业勇 王明 杨红丽 牛莹莹 廖康 《Agricultural Science & Technology》 CAS 2016年第3期577-583,共7页
[Objective] The aims of this study were to understand the flowering biological characteristics of Prunus domestica ×armeniaca and analyze its differences with other apricot varieties and plum varieties. [Method] ... [Objective] The aims of this study were to understand the flowering biological characteristics of Prunus domestica ×armeniaca and analyze its differences with other apricot varieties and plum varieties. [Method] Taking three varieties of Prunus domestica ×armeniaca as the research object, the phenophase of blooming,morphology characteristics of floral organs and development characteristics of floral organs were observed, pollen amount, pollen viability and stigma receptivity were measured. [Result] The results showed that three varieties of Prunus domestica×armeniaca were in blossom in early April, the florescence were relatively late for 8-12 d comparing with the varieties of apricot, the florescence were relatively similar to the P. domestica L. Morphology characteristics of floral organs of three varieties of Prunus domestica×armeniaca had few differences, were relatively similar to two varieties of plum, and they all had high percent of middle-style and long-style flower.The pollen amount of three varieties of Prunus domestica ×armeniaca had a little differences comparing with two varieties of plum, but were lower than three varieties of apricot. There were some differences in pollen viability, the germination percentage of pollen of ‘Konglongdan' was relatively high, was 51.6%; The pollen amount of ‘Fengweihuanghou' was relatively high, was 880.8 per anther; ‘Weidi' had fewer pollen amount, and the pollen viability was just 2.1%; Three varieties of Prunus domestica ×armeniaca all had strong stigma receptivity on the bloom day, and the stigma receptivity continued exist until the day that 5 days after blooming. [Conclusion] The florescence of three varieties of Prunus domestica ×armeniaca were relatively concentrated, and the rate of pistil abortion was lowest, the variation intensity of stigma receptivity and sustainable time of three varieties of Prunus domestica×armeniaca almost had a little differences comparing with a variety of plum, but slightly more than three varieties of apricot. 展开更多
关键词 Prunus domestica×armeniaca Blooming phenophase Floral organs Pollen viability Stigma receptivity
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Thermodynamic consistent phase field model for sintering process with multiphase powders 被引量:1
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作者 张瑞杰 陈忠伟 +1 位作者 方伟 曲选辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期783-789,共7页
A thermodynamic consistent phase field model is developed to describe the sintering process with multiphase powders. In this model, the interface region is assumed to be a mixture of different phases with the same che... A thermodynamic consistent phase field model is developed to describe the sintering process with multiphase powders. In this model, the interface region is assumed to be a mixture of different phases with the same chemical potential, but with different compositions. The interface diffusion and boundary diffusion are also considered in the model. As an example, the model is applied to the sintering process with Fe-Cu powders. The free energy of each phase is described by the well-developed thermodynamic models, together with the published optimized parameters. The microstructure and solute distribution during the sintering process can both be obtained quantitively. 展开更多
关键词 phase field model SINTERING multiphase powder THERMODYNAMICS
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Optimization of Fermentation Conditions of Acid Resistant α-amylase Producing Strain 被引量:2
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作者 刘雅琴 乌日娜 段金华 《Agricultural Science & Technology》 CAS 2010年第8期73-76,共4页
[Objective] The aim was to optimize the fermentation conditions of acid resistant α-amylase producing strain. [Method] Based on the selection of an acid resistant α-amylase producing strain,the fermentation conditio... [Objective] The aim was to optimize the fermentation conditions of acid resistant α-amylase producing strain. [Method] Based on the selection of an acid resistant α-amylase producing strain,the fermentation conditions including C,N contents and initial pH of culture medium,seed age,inoculum size,rotation speed of shake flask and fermentation temperature were optimized. [Result] The optimum fermentation conditions for acid resistant α-amylase producing strain were:seed age 14 h,inoculum size 8%,initial pH 5.5,fermentation temperature 35 ℃,rotation speed 150 r/min,the volume of inoculum broth 25 ml,C content 1.0% and N content 0.5%. [Conclusion] Under the optimum fermentation conditions,α-amylase activity reached 31.4 U/ml,which was 65.3 % higher than that before optimization. 展开更多
关键词 ALPHA-AMYLASE Enzyme activity FERMENTATION Optimization
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Existing state of potassium chloride in agglomerated sintering dust and its water leaching kinetics 被引量:8
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作者 彭翠 郭占成 张福利 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1847-1854,共8页
In order to examine the leaching rate of potassium chloride from the sintering dust by water,surface morphology and inner structure of the dust,especially the existing state of potassium chloride,were observed by scan... In order to examine the leaching rate of potassium chloride from the sintering dust by water,surface morphology and inner structure of the dust,especially the existing state of potassium chloride,were observed by scanning electron microscopy(SEM) and linear scanning technique via energy dispersive spectroscopy(EDS).The characterization shows that the sintering dusts are mostly porous composites or agglomerates of the fine dust particles with size less than 10 μm,and the potassium chloride and sodium chloride particles are partly covered by other water insoluble matters in the dust which consist of elements iron,calcium and etc.Exposure of potassium chloride in the agglomerated dust matrix of this kind suggests that the leaching can be simply perceived as the dissolution of water soluble matters in the dust.On-line monitor of specific electrical conductivity of the leaching system verifies the prediction that leaching kinetics of potassium chloride from the sintering dust fits dissolution model well.Leaching equilibrium can be reached within 5 min with potassium leaching ratio more than 95%. 展开更多
关键词 potassium chloride sintering dust LEACHING KINETICS surface exposure
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Invention and Utilization of Glutinous Sorghum Male Sterile Line 45A with High Starch and High Combining Ability 被引量:1
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作者 丁国祥 赵甘霖 +2 位作者 陈国民 倪先林 刘天朋 《Agricultural Science & Technology》 CAS 2015年第3期486-492,共7页
45A is a glutinous sorghum male sterile line with high starch and high combining ability bred by Rice and Sorghum Institute of Sichuan Academy of Agricultural Sciences in 1998, it is a coeno-species taking non-glutino... 45A is a glutinous sorghum male sterile line with high starch and high combining ability bred by Rice and Sorghum Institute of Sichuan Academy of Agricultural Sciences in 1998, it is a coeno-species taking non-glutinous maintainer line TL169-239B which bred by Tieling Institute of Agricultural Sciences in 1991 as the female parent and glutinous maintainer line72B bred by the authors' institute as the male parent, then, based on the backcross breeding between glutinous single plant chosen from F2 segregation population and Tx623A. There are ten hybrid sorghum varieties which already have been examined and approved by national and above provincial(municipal) level units; the patent of this breeding method has been authorized (the patent number: ZL 2012 1 0129155.6); 45A is protected by the Right of New Varieties of Plants, MOA, P.R. China (the variety right number: CNA20090576.1). In this paper, the breeding process of 45A and the characteristics of 45A sterile line and its hybrid sorghum were summed up, what's more, the technical key points of high-yielding breed of 45A and the production of hybrid sorghum seeds were introduced, to provide data for further popularizing the sterile line. 展开更多
关键词 SORGHUM Male sterile line STARCH Combining ability Glutinous Invention: Utilization
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Water leaching kinetics and recovery of potassium salt from sintering dust 被引量:10
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作者 詹光 郭占成 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3770-3779,共10页
Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that t... Surface morphology and inner structure of the dust were observed by ICP-AES, SEM-EDS and XRD to examine the strengthening measures of leaching potassium salt from the sintering dust by water. The results showed that the main component of the sintering dust was iron-oxygen compound, with KCl adsorbed on its surface. Leaching experiments showed that the KCl in the ESP dust could be separated and recovered by water leaching and fractional crystallization. The yield of K-Na vaporized crystalline salt was 18.56%, in which the mass fractions of KCl, NaCl, CaSO4 and K2SO4 were about 61.21%, 13.40%, 14.62%and 10.86%, respectively. The leaching kinetics of potassium salt from the sintering dust fits the external diffusion model well. The leaching speed and the leaching rate of the potassium salt can be increased by increasing the leaching temperature, strengthening the stirring speed and increasing the liquid-solid ratio. 展开更多
关键词 potassium salt sintering dust leaching kinetics intensified leaching
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LOESCHE磨液压系统的原理 被引量:2
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作者 刘宁昌 程福安 《新世纪水泥导报》 CAS 2008年第5期5-9,共5页
立磨运行中,磨辊非为自然状态施加粉磨力,而是依靠液气弹性杠杆系统作用,既保证施加一定(大小可调)的粉磨力,又使磨辊像悬挂在一个弹簧上,能够适应料床不同厚度的变化,将磨机运行时产生的振动能量最大程度地吸收,同时使粉磨力基本保持不... 立磨运行中,磨辊非为自然状态施加粉磨力,而是依靠液气弹性杠杆系统作用,既保证施加一定(大小可调)的粉磨力,又使磨辊像悬挂在一个弹簧上,能够适应料床不同厚度的变化,将磨机运行时产生的振动能量最大程度地吸收,同时使粉磨力基本保持不变,保证粉磨过程的连续稳定,并且便于自动实现磨机启停过程的升降辊功能。针对粉磨不同性质的物料,通过调节液压系统设定不同的粉磨力和弹性刚度,以使磨机(生产线)能够适应粉磨不同的物料,处于最佳粉磨状态。 展开更多
关键词 液压 弹性 刚度
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Structural and mechanical properties of CuZr/AlN nanocomposites 被引量:1
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作者 谷曼 吴玉程 +1 位作者 焦明华 黄新民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期380-384,共5页
Powder metallurgy method was used to prepare copper alloy nanocomposites (CuZr/AlN) with high strength and conductivity. Optical microscopy, high-resolution transmission electron microscopy and other methods were ad... Powder metallurgy method was used to prepare copper alloy nanocomposites (CuZr/AlN) with high strength and conductivity. Optical microscopy, high-resolution transmission electron microscopy and other methods were adopted to study the impact of different sintering technologies on the structural and mechanical properties as well as the impact of solution and aging treatments on the mechanical properties of CuZr/AlN. The result shows that the specimen has a dense structure, and the size of the crystal grain is around 0.2 μm. The Brinell hardness of the specimen increases with the increase in re-pressing pressure and sintering temperature. The Brinell hardness of specimen also increases with the increase in zirconium content. However, above 0.5%(mass fraction) of zirconium content, the Brinell hardness of the nanocomposites is reduced. The buckling strength of the specimens increases with the increase in re-pressing pressure and sintering temperature. The buckling strength is the highest when the zirconium content is 0.5%. The Brinell hardness is lower after solution and aging treatments at 900 ℃. The Brinell hardness of the CuZr/AlN series specimen after the aging treatment at 500 ℃ or 600 ℃ increases. The specimen was also over aged at 700 ℃. 展开更多
关键词 CuZr/AlN nanocomposites powder metallurgy mechanical properties
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Study on Starch Properties of Rice Enriched with Resistant Starch 被引量:1
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作者 林静 孙宝霞 +3 位作者 方先文 王艳平 张所兵 汪迎节 《Agricultural Science & Technology》 CAS 2014年第3期355-358,378,共5页
This study aimed to compare starch properties among rice germplasms with different contents of resistant starch. Rice germplasms with significant differ- ences in resistant starch content were screened by the rice ger... This study aimed to compare starch properties among rice germplasms with different contents of resistant starch. Rice germplasms with significant differ- ences in resistant starch content were screened by the rice germplasm resource project team in Jiangsu Academy of Agricultural Sciences, to analyze the differences in RVA eigenvalues and starch crystal thermodynamic properties using differential scanning calorimeter (DSC). The result showed that three rice materials with high contents of resistant starch exhibited low breakdown viscosity and high setback vis- cosity; three rice materials with low contents of resistant starch exhibited high breakdown viscosity and low setback viscosity. Significant differences were observed in RVA eigenvalues and starch crystal thermodynamic properties among rice germplasms with different contents of resistant starch, which provided new indices for breeding functional rice cultivars with high resistant starch content. 展开更多
关键词 RICE Resistant starch RVA eigenvalue Starch crystal thermodynamics
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Changes of Granule Structure and Enzyme Hydrolysability of Starch in Upper Flue-cured Tobacco Leaves During Bulk Flue-curing 被引量:2
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作者 贺帆 王涛 +5 位作者 田斌强 宋朝鹏 史龙飞 徐成龙 詹军 宫长荣 《Agricultural Science & Technology》 CAS 2012年第12期2642-2647,共6页
[Objective] This study aimed to investigate the changes of granule struc- ture, characteristic and related enzymatic activity of starch in upper flue-cured tobac- co leaves during bulk flue-curing process, to provide ... [Objective] This study aimed to investigate the changes of granule struc- ture, characteristic and related enzymatic activity of starch in upper flue-cured tobac- co leaves during bulk flue-curing process, to provide theoretical basis for reasonably regulating the starch content in upper flue-cured tobacco leaves and improving the quality of upper flue-cured tobacco leaves. [Method] Changes of amylase activity, enzyme hydrolysability and granule structure of starch in upper flue-cured tobacco leaves were studied during flue-curing process using conventional physical and chemical analysis and SEM. [Result] During the flue-curing process, the starch con- tent of tobacco leaves changed greatly at yellowing stage, and the activity of amy- lase presented the double-peak curve. The SEM observation results showed that most of the starch granules in fresh tobacco leaves were spheroidal and long cylin- drical, while some individuals were in irregular shape, with obvious groove-like in- vagination and layered structure on granule surface; during the flue-curing process, a large amount of starch granules showed layered structure on the surface at yellow- ing stage, and the long cylindrical starch granules were reduced greatly; at the end of flue-curing, there were barely any long cylindrical starch granule in flue-cured to- bacco leaves. Average long-axis-diameter of starch granules in fresh tobacco leaves was 3.21 μm, showing an overall gradually increasing trend during the flue-curing process, which was significantly enhanced at 38 and 42 ℃. The diameter of starch granules increased by more than 60% at the end of 42 ℃ and there was no re- markable difference after 47 ℃. During the flue-curing process, enzyme hydrolysabil- ity of starch in flue-cured tobacco leaves first increased, reached a peak at 38 ~C, and then decreased. [Conclusion] During the bulk flue-curing, the yellowing stage is the critical period for starch content, granule structure and characteristic changes of flue-cured tobacco leaves, it is of positive effects to improve the quality of upper flue-cured tobacco leaves by regulating the flue-curing conditions at yellowing stage. 展开更多
关键词 Flue-cured tobacco Bulk flue-curing Starch Granule structure Enzyme hydrolysability
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