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温度与光周期对樟子松实生苗针叶抗寒性的影响 被引量:10
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作者 王爱芳 张钢 +1 位作者 魏士春 崔同祥 《中国农学通报》 CSCD 2007年第2期156-161,共6页
为了研究温度和光周期对樟子松(Pinus SylvestrisL.var.mongolicaLitv.)抗寒发育的影响及两因子对抗寒性的影响是否呈加性,本实验对秋季停长了的2年生樟子松实生苗进行了4个不同温度+光周期处理:长光周期高温(16h/8h,15℃)(LDHT),长光... 为了研究温度和光周期对樟子松(Pinus SylvestrisL.var.mongolicaLitv.)抗寒发育的影响及两因子对抗寒性的影响是否呈加性,本实验对秋季停长了的2年生樟子松实生苗进行了4个不同温度+光周期处理:长光周期高温(16h/8h,15℃)(LDHT),长光周期低温(16h/8h,3℃)(LDLT),短光周期高温(8h/16h,15℃)(SDHT),短光周期低温(8h/16h,3℃)(SDLT)。处理时间为3个月。每隔2或3周取一次样,共取样5次。每次取样分别用电导法(EL)、褐变法(VSD)和荧光法(CF)测定针叶的抗寒性。结果表明:在给定的光周期与温度条件下,针叶的抗寒性达到相应的抗寒性固定水平;经不同处理的2年生樟子松苗其针叶抗寒锻炼速率不同,但不支持加性理论;三种方法测定的针叶的抗寒性有差异,但有较高的相关性。 展开更多
关键词 樟子松实生苗针叶 温度 光周期 抗寒 加性影响
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复发事件下一类加性乘性转移模型p阶矩指数稳定性 被引量:1
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作者 杜彦斌 戴家佳 金君 《应用数学学报》 CSCD 北大核心 2018年第5期642-652,共11页
复发事件数据频繁的出现在纵向研究中,本文基于生物医学中的单类型复发事件数据,提出了一类加性乘性转移模型,该模型包含了一些重要的半参数模型.同时,模型允许协变量具有加性和乘性的影响,且加性影响随时间而变化.利用广义估计方程的思... 复发事件数据频繁的出现在纵向研究中,本文基于生物医学中的单类型复发事件数据,提出了一类加性乘性转移模型,该模型包含了一些重要的半参数模型.同时,模型允许协变量具有加性和乘性的影响,且加性影响随时间而变化.利用广义估计方程的思想,对模型中未知参数和非参数函数进行了估计,并证明了所得估计的相合性和渐近正态性.最后,用数值模拟的方法验证了所提估计的可行性. 展开更多
关键词 复发事件数据 影响 转移模型 估计方程
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Layered double hydroxide-like Mg_3Al_(1–x)Fe_x materials as supports for Ir catalysts: Promotional effects of Fe doping in selective hydrogenation of cinnamaldehyde 被引量:4
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作者 Weiwei Lin Haiyang Cheng +3 位作者 Xiaoru Li Chao Zhang Fengyu Zhao Masahiko Arai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第5期988-996,共9页
Supported Ir catalysts were prepared using layered double hydrotalcite‐like materials,such as Mg3Al1-xFex,containing Fe and Al species in varying amounts as supports.These Ir catalysts were applied for the selective ... Supported Ir catalysts were prepared using layered double hydrotalcite‐like materials,such as Mg3Al1-xFex,containing Fe and Al species in varying amounts as supports.These Ir catalysts were applied for the selective hydrogenation of cinnamaldehyde(CAL).When x was changed from 0(Ir/Mg3Al)to 1(Ir/Mg3Fe),the rate of CAL hydrogenation reached a maximum at approximately x=0.25,while the selectivity to unsaturated alcohol,i.e.,cinnamyl alcohol,monotonously increased from 44.9%to 80.3%.Meanwhile,the size of the supported Ir particles did not change significantly with x,remaining at 1.7-0.2 nm,as determined by transmission electron microscopy.The chemical state of Ir and Fe species in the Ir/Mg3Al1-xFex catalysts was examined by temperature programmed reduction by H2 and X‐ray photoelectron spectroscopy.The surface of the supported Ir particles was also examined through the in‐situ diffuse reflectance infrared Fourier‐transform of a probe molecule of CO.On the basis of these characterization results,the effects of Fe doping to Mg3Al on the structural and catalytic properties of Ir particles in selective CAL hydrogenation were discussed.The significant factors are the electron transfer from Fe2+in the Mg3Al1–xFex support to the dispersed Ir particles and the surface geometry. 展开更多
关键词 Ir catalyst Layered double hydroxide Fe doping Support effect Selective hydrogenation CINNAMALDEHYDE
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浅议国内纯苯市场发展现状 被引量:1
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作者 潘项 《中国经贸》 2016年第13期191-191,共1页
随着2014年国际原油的断崖式下跌,国内纯苯进入了低价时代。通过分析近年来国内纯苯市场现状、变化趋势、价格走势以及加氢苯的影响性,找出纯苯市场的运行规律,并对未来纯苯市场的供需状况及运行趋势做出分析和预测。
关键词 纯苯市场 变化趋势 氢苯影响
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Research of Influence of Steam Contact Heating on Thermal Stability of a Wall of Glass Canning Jar
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作者 Yakov G. Verkhivkert Ella I. Altman 《Journal of Environmental Science and Engineering(B)》 2012年第3期293-298,共6页
One of ways of intensification of process of manufacture of heterogeneous tinned products of fruits and vegetables is the use of sated water steam (Patent of USSR No. 500792). This process at application as consumer... One of ways of intensification of process of manufacture of heterogeneous tinned products of fruits and vegetables is the use of sated water steam (Patent of USSR No. 500792). This process at application as consumer glass container for such products is especially effective. However, there are some questions which are connected with thermal influence on glass container at realization of such heating. The given research is devoted as the decision of practical questions arising at process engineers. 展开更多
关键词 FRUITS VEGETABLES glass canning jar heat water steam.
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Effect of Ammonia on the Performance of Catalysts for Selective Hydrogenation of 1-Methylnaphthalene 被引量:4
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作者 Ge Panzhu Ren Liang +1 位作者 Gao Xiaodong Li Dadong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期1-7,共7页
The effect of ammonia on the catalytic performance for 1-methylnaphthalene(1-MN) selective hydrogenation saturation was studied with Co-Mo/γ-Al_2O_3, Ni-W/γ-Al_2O_3, Ni-Mo/γ-Al_2O_3, and Ni-Mo-W/γ-Al_2O_3 catalyst... The effect of ammonia on the catalytic performance for 1-methylnaphthalene(1-MN) selective hydrogenation saturation was studied with Co-Mo/γ-Al_2O_3, Ni-W/γ-Al_2O_3, Ni-Mo/γ-Al_2O_3, and Ni-Mo-W/γ-Al_2O_3 catalysts. The results indicated that Ni-Mo-W/γ-Al_2O_3 catalyst exhibited the best performance for saturation of 1-MN. The introduction of NH3 remarkably inhibited the hydrogenation of 1-MN in the dynamic control area, but it had no effect in the thermodynamic control area. Besides, the mono-aromatics selectivity on the Ni-Mo-W and Ni-Mo catalysts was enhanced. However, it had little effect on the Ni-W and Co-Mo catalysts. 展开更多
关键词 1-methylnaphthalene(1-MN) selectivity hydrogenation catalyst hydrogenation saturation
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基于UKF的雷达和机载ESM扩维跟踪 被引量:6
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作者 张翔宇 王国宏 +1 位作者 王娜 张静 《国外电子测量技术》 2011年第9期30-32,39,共4页
为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标... 为有效提高异类传感器融合跟踪的效果,提出了一种基于UKF的雷达和机载ESM扩维跟踪算法。首先将目标和机载ESM的状态信息组合起来,形成一个高维的状态向量,从而有效抑制滤波中GPS定位误差所带来的影响;接着在此基础上采用UKF来实现目标的定位跟踪,以求进一步减小扩维后线性化误差加大等问题的影响。仿真结果表明,该算法可更好地实现对目标的定位跟踪。 展开更多
关键词 不敏卡尔曼滤波 扩维跟踪 雷达
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