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装配生产线的平衡问题研究 被引量:28
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作者 杜运普 杨月新 《机械设计与制造》 2003年第2期104-106,共3页
讨论了装配过程中的生产平衡问题,介绍了最大候选原则和分级位置权(RPW)法2种装配线平衡的人工方法,结合实例介绍了2种方法在装配线平衡问题上的应用,并对比分析了2种不同方法分配装配作业的装配线效率。
关键词 装配生产线 装配周期 平衡延迟 最大候选 rpw 分级位置权
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The Role of Mineral and Natural Oils in Integration with Inorganic Salts and Some Insecticides in Suppressing the Invasion of the Red Palm Weevil Rhynchophorus ferrugineus (RPW) Affecting Date Palms with Estimation of Its Residues in the Resulting Date Fruits
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作者 Mohammad I. Mogahed 《Advances in Entomology》 2023年第4期300-308,共9页
Applied experiments were conducted in the palm orchard in the Nubaria region. The orchard includes the varieties of Al-Barhi (imported) and Zaghloul (local) to examine the efficacy of some natural materials alone and ... Applied experiments were conducted in the palm orchard in the Nubaria region. The orchard includes the varieties of Al-Barhi (imported) and Zaghloul (local) to examine the efficacy of some natural materials alone and in combination with some pesticides against the Red Palm Weevil Rhynchophorus ferrugineus (RPW) that infects palm trees in Egypt. Most insects caught by light traps, which have a role in the spread of the red palm weevil in palm groves, appear in early February and March. Peak numbers for the month of May until September namely Phyllgnathus excavatus. Pseudophilus testaceus, Phonapata frontalis, and Oryctes elegans. The neglected gardens of date palms are more compensating for insect infestation than those maintained in terms of agricultural and pest control services. Individual injection of insecticide (Mosspilan) was the most potent against RPW-infested Barhi var. with a recovery rate of 91.7%, followed by Selikron at 80%, and finally Saydon at 37.5%. Injection of the car oil used with Mosspilan followed by Selikron was effective against RPW. No significant difference between treatments of injection (F-value: 1.2). Mixing injection of mineral oils with chemical pesticides is effective against red palm weevil after two successive seasons. As a result, the pesticide was poured around the affected palm root, with a low recovery rate. There is no effect of palm spray. The best way to control the red palm weevil is the method of injecting the tested material (single or mixed) with the pure pesticide into the trunk of the infected palm tree. The tested pesticide residues gradually decrease as the period after application is prolonged with an average loss of 0.12, 0.02 and 0.07 ppm after 90 consecutive days. . 展开更多
关键词 rpw Palm Varieties Light Traps Mineral Oil PESTICIDES
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Field Exploration of the Efficacy of Some Friendly Products in Combination with Some Pesticides against the Red Palm Weevil Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) and Its Effect on Total Carbohydrates and Micronutrients in the Resulting Date Fruits
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作者 Mohammad I. Mogahed 《Advances in Entomology》 2022年第4期275-286,共12页
Experiments were carried out against the red palm weevil, Rhynchophorus ferrugineus (Oliv.) (RPW in a private palm orchard containing varieties of Samani (domestic) and Ikhlas (imported) infested with the red palm wee... Experiments were carried out against the red palm weevil, Rhynchophorus ferrugineus (Oliv.) (RPW in a private palm orchard containing varieties of Samani (domestic) and Ikhlas (imported) infested with the red palm weevil Rhynchophorus ferrugineus (Oliv.) (RPW) in El-Marg area, Cairo Governorate, Egypt, using Petroleum oil, Jojoba oil, and Inorganic salts, singly and mixed with each of insecticides (Acetamiprid, Profenofos, Dimethoate) by injection and spraying of infested palm trunks, as well as pouring these substances into pits around the roots of the affected palm trees. The data showed that Acetamiprid was the most effective against RPW. The effective mixtures against R. ferrugineus were Jujuba oil with Acetamiprid, also used car oil with inorganic salts, which resulted in 100% recovery of treated palm. Continuing treatment of infested palms for 6 consecutive months by injecting used car oil mixed with inorganic saline solution resulted in 100% recovery for both date palm cultivars. Spraying these substances on the affected trunks had no effect on RPW. Pouring the tested solutions around the roots of the affected palm had the least effect against RPW. Injection of the tested pesticides into the infested trunks increased the concentrations of carbohydrates and total micronutrients (Fe<sup>+</sup>, Mn<sup>+</sup>, Zn<sup>+</sup>, and Cu<sup>+</sup>) in the produced fruits more than those obtained by palms treated with mineral oils and inorganic salt, compared to the control group. There is a significant difference between the treatments. 展开更多
关键词 rpw PESTICIDES Natural Oils Jujupa Oil Inorganic Salts
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Identification and Characterization of Bacterial Community Associated with the Chewed Feeding Waste of Red Palm Weevil in Infested Date Palm Trees
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作者 AbdulAziz M. A. Mohamed Muhammad Farooq Malabika Roy Pathak 《Advances in Bioscience and Biotechnology》 2020年第3期80-93,共14页
Red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), is considered one of the most damaging insect pests of date palms in the Kingdom of Bahrain. Large scale infestation of RPW to da... Red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), is considered one of the most damaging insect pests of date palms in the Kingdom of Bahrain. Large scale infestation of RPW to date palm trees leads to excessive feeding activity of the RPW larvae, which is carried out by microorganisms present within RPW and producing a wet fermenting material inside the trunk. Culture dependent-bacteria were isolated from feeding waste and identified by the sequencing of the 16S rRNA gene using 8F and 1492R universal primers. Among the culture-dependent isolated bacteria, 80% were identified by comparing 16S rRNA gene sequence in NCBI database, using BLAST program in GenBank. 85% of the identified bacteria were Gram-positive while the rest of them were Gram-negative. A high abundance of bacteria were from the Bacillaceae family and sixteen different species of Bacillus were identified in comparison with NCBI GenBank. The 16S rRNA gene sequences of identified bacterial strains have been submitted to GenBank. The phylogenetic relationship was studied using 16S rRNA gene sequences, the Gram-negative bacteria came in one clade while Gram-positive different Bacillus sp. and strains showed evolutionary closeness to each other and accordingly, they came in one major clade under three different sub-clades in the phylogenetic tree. The findings of new Bacillus strains in the natural habitat of the date plam trees in the Kingdom of Bahrain, pledge a vast area of research on RPW bio-control research arena. 展开更多
关键词 Red PALM WEEVIL (rpw) Bacteria DATE PALM FEEDING WASTE 16S RRNA
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多次循环塑性变形对Mg_2Si/Mg-5Zn-2.5Er复合材料组织与性能的影响
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作者 秦亚灵 杜文博 +2 位作者 王旭东 王朝辉 李淑波 《特种铸造及有色合金》 CAS CSCD 北大核心 2010年第6期546-549,共4页
经多次循环塑性变形(RPW)、固相原位合成和挤压成型,制备了Mg2Si/Mg-5Zn-2.5Er复合材料。多次循环塑性变形次数分别为100次、200次、300次和400次。通过XRD、SEM、OM和力学性能测试等方法,研究了RPW次数对复合材料组织、性能的影响规律... 经多次循环塑性变形(RPW)、固相原位合成和挤压成型,制备了Mg2Si/Mg-5Zn-2.5Er复合材料。多次循环塑性变形次数分别为100次、200次、300次和400次。通过XRD、SEM、OM和力学性能测试等方法,研究了RPW次数对复合材料组织、性能的影响规律。结果表明,随着RPW次数的增加,增强相粒子Mg2Si的尺寸不断减小、分布趋向均匀。当RPW次数为200次时,复合材料的综合性能最佳。其平均晶粒尺寸为1.8μm,较未经RPW加工试样降低了81.6%,晶粒的尺寸变化主要是冷变形过程的晶粒细化与高温反应以及热挤压过程中动态再结晶的晶粒长大相互作用的结果。其抗拉强度为394MPa,比未经RPW加工试样提高了25.4%,伸长率为5.5%。通过对增强机制的研究,发现多次循环塑性变形制备的复合材料的主要强化机制是晶粒细化。 展开更多
关键词 复合材料 多次循环塑性变形 力学性能 微观组织
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An Advanced Catch-and-Release Trap for Controlling the Red Palm Weevil
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作者 Nabawy Metwaly 《Journal of Life Sciences》 2013年第1期84-88,共5页
The aim of the research was to develop a catch-and-release trap for monitoring and controlling RPW (Rhynchophorus ferrugineus, red palm weevil). The RPW insects were attracted through the use of an aggregation phero... The aim of the research was to develop a catch-and-release trap for monitoring and controlling RPW (Rhynchophorus ferrugineus, red palm weevil). The RPW insects were attracted through the use of an aggregation pheromone located into a dispenser inside the trap. The RPW adults entered through an entrance door into a sterilization room where they were sprayed with a solution containing the chemical sterilizer product "lufenuron". The adults were then forced to move into a contamination room where it was present a wet media containing spores and hyphae of Metarhizium anisopliae and spores and crystalline insecticidal proteins of Bacillus thuringensis. The sterilized and infected RPW adults were counted and released into the environment where they reached new palms and join natural populations of RPW. Preliminary experiments showed that the catch-and-release trap was able to reduce the fertility of RPW adults and to increase their mortality after contamination with entomopathogens. Moreover, the infected RPW adults were able to infect untreated RPW larvae leading to a larvae mortality of 93% within 30 days. In conclusion, the advanced catch-and-release trap represents a safe and effective tool to monitor and control the population of RPW pest without environmental pollution and risks for human health. 展开更多
关键词 rpw TRAP PALM biological control.
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RPW方法在本科教学计划制定中的应用
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作者 王海燕 《教育教学论坛》 2014年第52期148-149,共2页
本科教学涉及课程较多,课程之间存在约束关系,先修课程需要提前学完才能进行后续学习。这种约束关系跟生产线平衡中的紧前关系类似,可以利用线平衡中常用的RPW方法制定课程的开设顺序和学期分配。本文首先论述了RPW的方法及实现步骤,然... 本科教学涉及课程较多,课程之间存在约束关系,先修课程需要提前学完才能进行后续学习。这种约束关系跟生产线平衡中的紧前关系类似,可以利用线平衡中常用的RPW方法制定课程的开设顺序和学期分配。本文首先论述了RPW的方法及实现步骤,然后通过实例介绍了RPW方法在本科教学计划制定中的应用流程,最后跟ISM方法进行比较。分析结果表明,RPW方法从应用的方便性和程序的可实现性方面都优于ISM方法,可以在教学计划制定中推广应用。 展开更多
关键词 rpw 位置权重法 教学计划 本科教学
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PAPP2C Interacts with the Atypical Disease Resistance Protein RPW8.2 and Negatively Regulates Salicylic Acid-Dependent Defense Responses in Arabidopsis 被引量:7
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作者 Wen-Ming Wang Xian-Feng Ma +5 位作者 Yi Zhang Ming-Cheng Luo Guo-Liang Wang Maria Bellizzi Xing-Yao Xiong Shun-Yuan Xiao 《Molecular Plant》 SCIE CAS CSCD 2012年第5期1125-1137,共13页
Many fungal and oomycete pathogens differentiate a feeding structure named the haustorium to extract nutrition from the plant epidermal cell. The atypical resistance (R) protein RPW8.2 activates salicylic acid (SA... Many fungal and oomycete pathogens differentiate a feeding structure named the haustorium to extract nutrition from the plant epidermal cell. The atypical resistance (R) protein RPW8.2 activates salicylic acid (SA)-dependent, haustorium-targeted defenses against Golovinomyces spp., the causal agents of powdery mildew diseases on multiple plant species. How RPW8.2 activates defense remains uncharacterized. Here, we report that RPWS.2 interacts with the phytochrome-associated protein phosphatase type 2C (PAPP2C) in yeast and in planta as evidenced by co- immunoprecipitation and bimolecular fluorescence complementation assays. Down-regulation of PAPP2C by RNA interfer- ence (RNAi) in Col-0 plants lacking RPWS.2 leads to leaf spontaneous cell death and enhanced disease resistance to powdery mildew via the SA-dependent signaling pathway. Moreover, down-regulation of PAPP2C by RNAi in the RPW8.2 background results in strong HR-like cell death, which correlates with elevated RPWS.2 expression. We further demonstrate that hemagglutinin (HA)-tagged PAPP2C prepared from tobacco leaf cells transiently transformed with HA-PAPP2C possesses phosphatase activity. In addition, silencing a rice gene (Os04g0452000) homologous to PAPP2C also results in spontaneous cell death in rice. Combined, our results suggest that RPW8.2 is functionally connected with PAPP2C and that PAPP2C negatively regulates SA-dependent basal defense against powdery mildew in Arabidopsis. 展开更多
关键词 ARABIDOPSIS PAPP2C rpw8 protein phosphatase powdery mildew RESISTANCE SA-signaling.
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A Heuristic Method for Two-sided Assembly Line Balancing Problem 被引量:5
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作者 秦杏敏 金烨 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期61-65,共5页
A two-sided assembly line is typically found in plants producing large-sized products. Its advantages over a one-sided line and the difficulties faced in two-sided line balancing problems were discussed. A mathematica... A two-sided assembly line is typically found in plants producing large-sized products. Its advantages over a one-sided line and the difficulties faced in two-sided line balancing problems were discussed. A mathematical model for two-ALB problem was suggested. A modification of the “ranked positional weight” method, namely two-ALB RPW for two-ALB problems was developed. Experiments were carried out to verify the performance of the proposed method and the results show that it is effective in solving two-sided assembly line balancing problems. 展开更多
关键词 two-sided assembly lines assembly line balancing(ALB) task delay ranked positional weight(rpw)
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葡萄中RPW8.2同源基因克隆与表达分析 被引量:6
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作者 马辉 韩永涛 +3 位作者 高玉荣 徐虹 王跃进 文颖强 《西北林学院学报》 CSCD 北大核心 2015年第1期60-68,共9页
利用同源克隆技术分别从白河35-2、广西-1、黑比诺、五月紫4种葡萄中克隆得到了拟南芥广谱抗病基因RPW8.2的同源基因,分别命名为VpR8 H-BH2、VpR8 H-GX1、VvR8 H-PN和VvR8 H-MP,氨基酸多序列比对和系统发育分析显示,该4条序列均属于RPW... 利用同源克隆技术分别从白河35-2、广西-1、黑比诺、五月紫4种葡萄中克隆得到了拟南芥广谱抗病基因RPW8.2的同源基因,分别命名为VpR8 H-BH2、VpR8 H-GX1、VvR8 H-PN和VvR8 H-MP,氨基酸多序列比对和系统发育分析显示,该4条序列均属于RPW8.2同源基因。4种葡萄R82 H基因cDNA开放阅读框分别为2 457bp、2 445bp、2 445bp和2 448bp,分别编码819、815、815和816个氨基酸。采用半定量RT-PCR技术分析了R82 H基因在4种葡萄根、茎、成熟叶、幼嫩叶、卷须不同组织中的表达模式,R82 H基因在不同葡萄组织中均有表达,但是表达丰度不尽相同,其中,在白河35-2和五月紫葡萄成熟叶中表达量最高,而在广西-1和黑比诺中幼嫩叶片中表达量高于其他组织。 展开更多
关键词 rpw8.2 葡萄 同源克隆 表达分析
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RPW2表达载体构建及对烟草的遗传转化 被引量:4
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作者 何道一 段培树 陈丽萍 《核农学报》 CAS CSCD 北大核心 2009年第4期602-605,共4页
将RPW2基因插入表达载体pBI121的表达盒中,构建了RPW2组成型表达载体。通过农杆菌叶盘转化法转化烟草叶片,经卡那霉素筛选、PCR扩增和Southern杂交鉴定证明,RPW2基因已成功转入烟草细胞中,获得6个转基因株系。RT-PCR半定量分析表明,转... 将RPW2基因插入表达载体pBI121的表达盒中,构建了RPW2组成型表达载体。通过农杆菌叶盘转化法转化烟草叶片,经卡那霉素筛选、PCR扩增和Southern杂交鉴定证明,RPW2基因已成功转入烟草细胞中,获得6个转基因株系。RT-PCR半定量分析表明,转基因烟草株系的叶片中有RPW2基因的表达。不同转基因株系的基因表达量不同,转基因株系T-R2和T-R4表达量较高。转基因植株叶片上人工接种烟草赤星病菌液检测转基因植株的抗病性,结果表明,与对照植株相比,转RPW2基因植株对烟草赤星病抗性显著增强,说明RPW2基因在烟草中也具有抗病能力。另外,转基因株系间RPW2基因表达量虽有差异,但抗病性与其他株系相比没有显著差异。 展开更多
关键词 rpw2基因 转化 烟草 抗烟草赤星病
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白粉菌侵染后的拟南芥酵母双杂交cDNA文库构建及其利用 被引量:4
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作者 黄衍焱 杨玲珑 +3 位作者 王莹 李冉 鲁黎明 王文明 《植物病理学报》 CAS CSCD 北大核心 2015年第4期370-375,共6页
拟南芥广谱抗病基因RPW8对拟南芥白粉病菌、霜霉病菌和烟草花叶病毒等均具有抗性。为了深入研究其广谱抗病机制,筛选鉴定与RPW8具有直接相互作用的蛋白,我们以含有RPW8的拟南芥纯合转基因系S5为材料,接种拟南芥白粉菌系UCSC1,36 h后取样... 拟南芥广谱抗病基因RPW8对拟南芥白粉病菌、霜霉病菌和烟草花叶病毒等均具有抗性。为了深入研究其广谱抗病机制,筛选鉴定与RPW8具有直接相互作用的蛋白,我们以含有RPW8的拟南芥纯合转基因系S5为材料,接种拟南芥白粉菌系UCSC1,36 h后取样,构建了白粉菌侵染初期的拟南芥cDNA文库。为了提高文库对长片段基因5'端的覆盖率,分别使用含有oligo(d T)和oligo(d N)的接头引物反转录c DNA第一链,PCR扩增双链c DNA。将纯化后的双链c DNA与线性化载体p GADT7-Rec混合,利用同源重组技术在酵母菌株Y187中构建c DNA文库。经检测,文库转化效率为5.0×106/3μg p GADT7-Rec,滴度为2.5×108CFU·m L-1,插入片段长度在350~2 000 bp之间,平均插入片段大小为750 bp。用RPW8.1和RPW8.2构建诱饵载体,分别获得11和12个候选互作蛋白。结果表明此c DNA文库质量较好,适用于互作蛋白的筛选。 展开更多
关键词 rpw8 白粉菌 拟南芥 CDNA文库 酵母双杂交
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杏RPW8基因家族鉴定与表达量分析 被引量:4
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作者 许靖诗 王广军 +1 位作者 额尔敦达来 乌云塔娜 《中南林业科技大学学报》 CAS CSCD 北大核心 2019年第10期123-131,共9页
RPW8(Resistance to powdery mildew 8)不但对拟南芥白粉菌有抗性作用,同时也对烟草白粉菌、拟南芥霜霉菌和烟草花叶病毒等多种植物寄生性病原体都表现出较高的抗性,具有广谱抗病性。以杏全基因组数据为基础,鉴定RPW8家族成员,分析基因... RPW8(Resistance to powdery mildew 8)不但对拟南芥白粉菌有抗性作用,同时也对烟草白粉菌、拟南芥霜霉菌和烟草花叶病毒等多种植物寄生性病原体都表现出较高的抗性,具有广谱抗病性。以杏全基因组数据为基础,鉴定RPW8家族成员,分析基因家族特点及不同组织中表达量分析,有利于更加深入了解RPW8基因家族功能,为杏抗白粉病基因挖掘和抗白粉病育种提供理论参考。通过SMS、GSDS2.0、Expasy-protparam、MEME、MAGA6.0、TBtool等生物信息学工具对RPW8基因家族的核酸序列的特征、基因结构、蛋白质理化性质、蛋白保守结构域、家族系统进化关系、表达量等进行分析和预测。结果表明:从杏中共鉴定出16个RPW8家族基因,分别命名为LWMRPW8-1~LWMRPW8-16,内含子数量小于6个,16个基因的全长为360~4 864 bp,碱基G+C含量为37.39%~46.89%,碱基A+T的含量为53.11%~62.61%;杏RPW8基因家族编码的氨基酸分子量为13 653.93~92 617.92 Da,理论等电点为5.42~9.47,蛋白质不稳定性指数为22.94~61.18,氨基酸组成成分以亮氨酸(Leu)赖氨酸(Lys)为主;保守结构域分析结果显示杏RPW8家族主要含有10个Motify,其中Motif8、Motif9为特征结构域;系统进化树分析显示,蔷薇科植物RPW8家族基因聚为一类,LWMRPW8-7与拟南芥、杨树基因聚为一类。对杏RPW8基因在不同组织中的表达分析结果显示,16个基因在花、花芽、叶片、果肉、果仁中的表达量呈现较大差异。 展开更多
关键词 rpw8 基因家族 表达量
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反复塑性变形对SiCp/AZ31镁基复合材料组织和性能的影响 被引量:2
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作者 周天承 杜文博 +1 位作者 秦亚灵 严振杰 《特种铸造及有色合金》 CAS CSCD 北大核心 2009年第12期1089-1091,共3页
采用反复塑性变形(RPW)技术,结合挤压工艺制备出SiC颗粒增强AZ31镁基复合材料,研究了循环次数(RPW次数)对SiCp/AZ31镁基复合材料显微组织和性能的影响。结果表明,反复塑性变形具有明显的AZ31基体晶粒细化、SiCp细化和分散作用,能显著提... 采用反复塑性变形(RPW)技术,结合挤压工艺制备出SiC颗粒增强AZ31镁基复合材料,研究了循环次数(RPW次数)对SiCp/AZ31镁基复合材料显微组织和性能的影响。结果表明,反复塑性变形具有明显的AZ31基体晶粒细化、SiCp细化和分散作用,能显著提高SiCp/AZ31复合材料的抗拉强度和硬度,并改善其塑性。在SiCp的体积分数为4%时,经RPW为300次的热挤压后,AZ31基体晶粒粒径达到最小值20μm,SiCp被粉碎成3μm以下的微粒,且弥散分布于合金基体中,复合材料的室温抗拉强度和硬度(HV)达到或接近最大值,分别为359MPa和107。 展开更多
关键词 反复塑性变形(rpw) 颗粒增强 镁基复合材料 AZ31镁合金 SICP
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RPW法在水泵厂装配线平衡上的应用 被引量:2
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作者 何军 张睿 《广西工学院学报》 CAS 2007年第4期86-90,共5页
以某水泵厂的装配流水线为研究对象,对其装配流程和节拍进行测定与分析,根据6σ理论确定每道工序的标准时间,根据每道工序的标准时间和作业顺序图,运用RPW(分级位置权法)对其进行平衡,以几个评价指标对装配流水线平衡前后的状况进行评价... 以某水泵厂的装配流水线为研究对象,对其装配流程和节拍进行测定与分析,根据6σ理论确定每道工序的标准时间,根据每道工序的标准时间和作业顺序图,运用RPW(分级位置权法)对其进行平衡,以几个评价指标对装配流水线平衡前后的状况进行评价,结果表明生产线总停顿时间减少,平衡率得到提高。 展开更多
关键词 生产装配线 流水线平衡 改进 rpw
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临床试验中自适应设计的urn模型和RPW规则及其模拟 被引量:2
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作者 王素珍 夏结来 +3 位作者 郑亮 于莉莉 李婵娟 王陵 《第四军医大学学报》 北大核心 2007年第24期2284-2286,共3页
目的:探讨临床试验中设计驱动型自适应设计的优缺点及适用范围.方法:通过对基于概率罐子(urn)模型的随机化胜者优先(RPW)规则的原理分析得出期望分配公式,并据此进行蒙特-卡罗(MonteCarlo)计算机模拟.结果:假定总体成功率分别为pA,pB的... 目的:探讨临床试验中设计驱动型自适应设计的优缺点及适用范围.方法:通过对基于概率罐子(urn)模型的随机化胜者优先(RPW)规则的原理分析得出期望分配公式,并据此进行蒙特-卡罗(MonteCarlo)计算机模拟.结果:假定总体成功率分别为pA,pB的两处理临床试验,当pA,pB不相等且pA+pB<1.5时,采用RPW规则能够将更多的受试者分配给成功率较高的处理组.结论:RPW规则可适用于临床试验中有一定响应延迟的情况,通过选择合适的RPW初始参数可减少样本方差,增加试验的稳定性. 展开更多
关键词 临床试验 自适应设计 模型 统计学 rpw规则 MONTE CARLO模拟
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抗白粉病基因RPW8的抗性作用研究进展 被引量:2
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作者 罗昌国 王三红 +2 位作者 袁启凤 郑伟 宋莎 《贵州农业科学》 CAS 2020年第1期52-58,共7页
RPW8基因是最初在拟南芥上发现具有白粉病抗性的重要抗病基因,其在不同种类植物中,甚至同种不同生态型中,基因序系和功能都有差异。对RPW8基因的位点、结构、与NBS-LRR类型R基因的关系、起源与进化、表达特点、功能与调控机制等方面的... RPW8基因是最初在拟南芥上发现具有白粉病抗性的重要抗病基因,其在不同种类植物中,甚至同种不同生态型中,基因序系和功能都有差异。对RPW8基因的位点、结构、与NBS-LRR类型R基因的关系、起源与进化、表达特点、功能与调控机制等方面的研究成果进行综述,并展望RPW8基因在种群关系、抗病育种上的应用价值,以期为白粉病抗性调控、抗性育种等研究或应用提供参考。 展开更多
关键词 白粉病 rpw8基因 基因结构 基因功能 调控机制
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草莓抗白粉病RPW8同源基因的序列特征分析 被引量:2
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作者 高凤菊 张淑红 +3 位作者 张运峰 宋瑞生 韩靖玲 刘海英 《唐山师范学院学报》 2020年第6期51-55,共5页
利用草莓基因组数据鉴定出15个草莓RPW8同源基因(FaRPW8.1,FaRPW8.2-1~14),它们之间的碱基比例差异较小,但编码蛋白的相对分子量相差较大,范围为14734.20~196956.90Da,理论等电点5.05~8.52,不稳定性指数范围39.35~53.50,脂肪族指数介于9... 利用草莓基因组数据鉴定出15个草莓RPW8同源基因(FaRPW8.1,FaRPW8.2-1~14),它们之间的碱基比例差异较小,但编码蛋白的相对分子量相差较大,范围为14734.20~196956.90Da,理论等电点5.05~8.52,不稳定性指数范围39.35~53.50,脂肪族指数介于93.19~108.68之间,氨基酸组成中以亮氨酸(Leu)和赖氨酸(Lys)为主。保守结构域分析结果显示草莓RPW8同源基因含有1~4个结构域,其中RPW8为特征结构域。系统进化分析显示,FaRPW8.2-12和FaRPW8.2-13同谷子、小麦、水稻RPW8聚为一类,FaRPW8.2-3与番茄、蜜柑、橙子等RPW8基因聚为一类,其余12个草莓RPW8基因同源基因与其它物种的亲缘关系较远,单独聚为一类。研究结果可为草莓抗病育种提供理论依据。 展开更多
关键词 草莓 rpw8基因 序列特征 白粉病
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巴西橡胶树HbRPW8基因克隆与表达分析
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作者 官鑫 涂敏 +3 位作者 蔡海滨 王云月 胡彦师 曾霞 《热带作物学报》 CSCD 北大核心 2022年第12期2395-2404,共10页
RPW8(resistance to powdery mildew locus 8)是对植物多种病害,尤其白粉病具有抗性的广谱抗病基因位点,通过对橡胶树RPW8基因进行克隆及表达分析,为橡胶树抗白粉病机制解析和分子育种等方面打下基础。以橡胶树‘热研73397’为材料,采用... RPW8(resistance to powdery mildew locus 8)是对植物多种病害,尤其白粉病具有抗性的广谱抗病基因位点,通过对橡胶树RPW8基因进行克隆及表达分析,为橡胶树抗白粉病机制解析和分子育种等方面打下基础。以橡胶树‘热研73397’为材料,采用RT-PCR克隆HbRPW8基因编码区(CDS)序列;对其进行生物信息学分析,并利用qRT-PCR方法,测定7种激素和白粉菌侵染不同时间、不同病害等级处理后RPW8基因表达量。该基因cDNA全长570 bp,编码189个氨基酸,该蛋白的分子量为21.73 kDa,等电点为9.23,脂肪系数为86.30,总平均亲水性指数为-0.404,为亲水性蛋白,共有8个磷酸化位点,无跨膜域和信号肽,定位于细胞核,具有RPW8的保守结构域,α-螺旋和无规则卷曲是HbRPW8蛋白二级结构的主要元件,分别占氨基酸序列的70.90%和22.22%。亲缘关系显示,HbRPW8基因与木薯RPW8基因相似性最高。过氧化氢(H_(2)O_(2))、水杨酸(SA)、乙烯利(ETH)、赤霉素(GA)和脱落酸(ABA)能迅速诱导HbRPW8转录本的表达,并在处理后0.5 h达到最高水平,分别约为对照的14倍、6倍、75倍、2.5倍和4倍;茉莉酸甲酯(MeJA)处理后6h达到最高水平,是对照的10倍左右;生长素处理后HbRPW8转录本显著下调;随着白粉菌侵染时间和病害等级的增加,HbRPW8的表达量均呈现先上升后下降的趋势。研究结果初步表明,HbRPW8可能参与橡胶树的抗病反应机制,为橡胶树抗病育种的研究提供参考。 展开更多
关键词 巴西橡胶树 Hbrpw8基因 QRT-PCR 生物信息学 rpw8
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多层面CT机剂量的测量与分析 被引量:2
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作者 余晓锷 占杰 张宁 《中国医学物理学杂志》 CSCD 2005年第6期695-696,744,共3页
目的:分析多层面CT(MSCT)中影响剂量的因素,探讨降低多层面CT中病人辐射剂量的方法。方法:采用标准CT剂量测试体模测量4层面CT的剂量,计算出加权CT剂量指数。结果:(1)所有影响单层面CT剂量的因素仍然影响M SCT,此外在MSCT中还有一些特... 目的:分析多层面CT(MSCT)中影响剂量的因素,探讨降低多层面CT中病人辐射剂量的方法。方法:采用标准CT剂量测试体模测量4层面CT的剂量,计算出加权CT剂量指数。结果:(1)所有影响单层面CT剂量的因素仍然影响M SCT,此外在MSCT中还有一些特殊因素影响CT剂量。(2)在MSCT中,高速度模式要比高质量模式节省50%的剂量。(3)在剂量剖面线宽度(RPW)保持不变时,改变层厚和层数不会影响剂量值。在所有扫描模式中,当RPW增加时,CTDI100w降低。结论:必须认识在M SCT中影响剂量的各种因素,在保证图像质量的前提下尽可能地降低辐射剂量。 展开更多
关键词 多层面CT机 剂量 图像质量 辐射剖面线宽度
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