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Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets
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作者 Benjamin R.Helmold Angela Ahrens +1 位作者 Zachary Fitzgerald P.Hande Ozdinler 《Neural Regeneration Research》 SCIE CAS 2025年第3期725-739,共15页
Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understan... Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. Protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous. 展开更多
关键词 als2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SPAST SPASTIN
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水稻乙酰乳酸合酶Ala179Val突变赋予ALS抑制剂类除草剂广谱抗性
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作者 安晨 韶也 +2 位作者 彭彦 毛毕刚 赵炳然 《植物遗传资源学报》 CAS CSCD 北大核心 2024年第2期259-269,共11页
为了鉴定新型水稻突变体ALS179对乙酰乳酸合酶(ALS,acetolactate synthase)抑制剂类除草剂的抗性,本研究以野生型水稻华航31(HH31)、耐咪唑啉酮除草剂水稻ALS627突变体和甲基磺酸乙酯(EMS,ethyl methyl sulfone)诱变的新型水稻突变体ALS... 为了鉴定新型水稻突变体ALS179对乙酰乳酸合酶(ALS,acetolactate synthase)抑制剂类除草剂的抗性,本研究以野生型水稻华航31(HH31)、耐咪唑啉酮除草剂水稻ALS627突变体和甲基磺酸乙酯(EMS,ethyl methyl sulfone)诱变的新型水稻突变体ALS179为试验材料,通过不同浓度下的4类乙酰乳酸合酶抑制剂类除草剂包衣浸种和苗期喷施处理,进一步测定表型及相关酶活性指标来探究突变体ALS179的抗性。结果表明,经过除草剂包衣浸种以及苗期喷施处理后,突变体ALS179对苯磺隆、咪唑乙烟酸、双草醚及啶磺草胺具有不同程度的抗性,且乙酰乳酸合酶、过氧化物酶、过氧化氢酶和超氧化物歧化酶的活性随除草剂浓度的升高呈下降趋势。除了20×,30×的咪唑乙烟酸处理条件下过氧化氢酶和过氧化物酶的酶活性低于野生型HH31外,其他处理条件下ALS179的乙酰乳酸合酶、超氧化物歧化酶、过氧化氢酶和过氧化物酶的酶活性均高于野生型HH31。因此,本研究发现Ala179Val突变赋予了对ALS抑制剂类除草剂的广谱抗性,为后续ALS类除草剂广谱抗性水稻品系的培育提供遗传种质资源。 展开更多
关键词 水稻 乙酰乳酸合酶 als抑制剂类除草剂 广谱抗性
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EMS诱变的水稻不同位点突变体对ALS抑制剂类除草剂抗性差异
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作者 周佳伟 王歆凯 +2 位作者 唐兆成 凌溪铁 张保龙 《江苏农业学报》 CSCD 北大核心 2024年第7期1153-1160,共8页
稻田杂草严重威胁水稻生长,培育抗除草剂水稻新品种,是高效解决稻田杂草危害的重要途径之一。本研究利用甲基磺酸乙酯(EMS)对华占水稻进行化学诱变,创建突变体,利用乙酰乳酸合成酶(ALS)抑制剂类除草剂甲咪唑烟酸(20 g/hm 2,有效成分)对... 稻田杂草严重威胁水稻生长,培育抗除草剂水稻新品种,是高效解决稻田杂草危害的重要途径之一。本研究利用甲基磺酸乙酯(EMS)对华占水稻进行化学诱变,创建突变体,利用乙酰乳酸合成酶(ALS)抑制剂类除草剂甲咪唑烟酸(20 g/hm 2,有效成分)对突变体进行筛选,获得抗甲咪唑烟酸突变体材料,并对上述突变体的OsALS基因序列进行分析,明确其突变类型。最后对不同突变类型对甲氧咪草烟和甲基二磺隆的交互抗性进行分析。结果表明,华占水稻经EMS诱变和甲咪唑烟酸筛选后共获得11株抗甲咪唑烟酸突变体材料,其突变类型为Pro171Leu、Ser627Cys、Ser627Asn和Gly628Glu 4种。其中,Ser627Cys为首次发现的突变类型。4种突变类型对甲咪唑烟酸的抗性水平存在一定的差异,Ser627Asn、Ser627Cys、Pro171Leu、Gly628Glu突变类型的抗性指数分别为8.71、5.16、3.28和3.69。4种突变类型对甲氧咪草烟和甲基二磺隆的抗性亦存在显著差异。其中,Ser627Asn突变类型对甲氧咪草烟的抗性最高,抗性指数为20.57,Gly628Glu对甲基二磺隆抗性最高,抗性指数为5.11。综上,本研究通过EMS诱变获得了4种抗ALS抑制剂类除草剂的华占水稻突变类型,并鉴定了其对甲咪唑烟酸的抗性差异及对甲氧咪草烟和甲基二磺隆的交互抗性,为进一步的抗除草剂水稻品种培育和除草剂轮换使用提供依据。 展开更多
关键词 水稻 als抑制剂类除草剂 EMS诱变 抗除草剂突变体
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抗ALS抑制剂类除草剂分子标记的开发及应用
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作者 桑世飞 孙晓涵 +5 位作者 姚国琴 马腾云 章怡静 郑阳阳 丰柳春 姬生栋 《中国稻米》 北大核心 2024年第4期17-23,共7页
杂草严重制约水稻生产,培育具有乙酰乳酸合成酶(acetolactate synthase,ALS)抑制剂的广谱抗除草剂水稻新品种是应对稻田杂草危害的有效途径之一。本研究鉴定了抗ALS抑制剂类除草剂金粳818与感除草剂日本晴ALS基因的差异位点,开发特异分... 杂草严重制约水稻生产,培育具有乙酰乳酸合成酶(acetolactate synthase,ALS)抑制剂的广谱抗除草剂水稻新品种是应对稻田杂草危害的有效途径之一。本研究鉴定了抗ALS抑制剂类除草剂金粳818与感除草剂日本晴ALS基因的差异位点,开发特异分子标记。对以携带ALS抗性基因型的金粳818、津稻372为亲本的杂交后代进行除草剂喷施和分子标记辅助选择。开发了818ALSF/R、HDALSF/R两对分子标记,可以快速区分纯合显性、杂合、纯合隐性3种基因型,且与除草剂喷施结果一致;选育得到22S9和22S4两份抗除草剂优异水稻种质资源材料。通过对杂交后代分子标记辅助选择可快速筛选出具有ALS除草剂抗性基因的种质资源材料,提高了在抗ALS抑制剂类除草剂水稻种质中的筛选效率。 展开更多
关键词 als除草剂 乙酰乳酸合成酶 水稻 除草剂抗性
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ALS抑制剂类除草剂抗性水稻品系迁粳187选育及抗性鉴定
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作者 郭新亚 陈春 +3 位作者 李凡 王飞飞 史玉良 陈卫军 《大麦与谷类科学》 2024年第3期25-32,共8页
乙酰乳酸合酶[ALS,也称为乙酰羟酸合酶(AHAS),EC 4.1.3.18]抑制剂类除草剂是目前治理水稻田内杂草的高效化学防除方法,以金粳818、迁粳187这2个抗性水稻品种(系)为材料,徐稻3号为敏感型对照,分析经咪唑乙烟酸处理后靶标基因的相对表达... 乙酰乳酸合酶[ALS,也称为乙酰羟酸合酶(AHAS),EC 4.1.3.18]抑制剂类除草剂是目前治理水稻田内杂草的高效化学防除方法,以金粳818、迁粳187这2个抗性水稻品种(系)为材料,徐稻3号为敏感型对照,分析经咪唑乙烟酸处理后靶标基因的相对表达量。研究发现,抗性材料的靶标基因相对表达量逐步下降,且最终下降至正常水平的60%左右。离体酶活检测结果表明,金粳818、迁粳187这类ALS发生Ser-653-Asn氨基酸替换的材料对咪唑乙烟酸的抗性是敏感型材料徐稻3号的千倍以上。 展开更多
关键词 als 除草剂 金粳818 迁粳187
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基于改进的ALS协同过滤图书推荐算法研究
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作者 王倩丽 《微型电脑应用》 2024年第6期193-196,共4页
为了解决传统协同过滤算法存在着数据稀疏性、准确性以及图书偏好的量化等问题,获得更加理想的图书推荐效果,基于ALS模型的算法原理,使用读者图书借还记录的平均借阅时长生成读者图书偏好矩阵,引入Pearson相似度分析读者图书相似度,改进... 为了解决传统协同过滤算法存在着数据稀疏性、准确性以及图书偏好的量化等问题,获得更加理想的图书推荐效果,基于ALS模型的算法原理,使用读者图书借还记录的平均借阅时长生成读者图书偏好矩阵,引入Pearson相似度分析读者图书相似度,改进ALS模型造成的因子信息丢失问题,填充未评分项数据,并设计了算法实现流程,为特定读者推荐其偏好图书,通过实验验证算法的准确性。实验结果表明,改进的ALS算法的RMSE值降低了8.2个百分点,推荐算法的性能及准确度都有所提升。 展开更多
关键词 推荐算法 矩阵分解 als 协同过滤
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预热温度对激光选区熔化成形30%SiC_(p)/AlSi10Mg复合材料力学性能的影响 被引量:1
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作者 郭耀旗 唐敏 +4 位作者 马红林 魏文猴 王林志 范树迁 张祺 《材料导报》 EI CAS CSCD 北大核心 2024年第3期154-160,共7页
基板常温工况下激光选区熔化成形中等体积分数SiC_(p)/Al复合材料存在孔洞、裂纹等冶金缺陷,从而导致成形零件致密度低、力学性能差等问题。首先研究了固定优化成形工艺参数时,基板预热温度(200~400℃)对45μm的30%(质量分数,下同)SiC_(... 基板常温工况下激光选区熔化成形中等体积分数SiC_(p)/Al复合材料存在孔洞、裂纹等冶金缺陷,从而导致成形零件致密度低、力学性能差等问题。首先研究了固定优化成形工艺参数时,基板预热温度(200~400℃)对45μm的30%(质量分数,下同)SiC_(p)/AlSi10Mg成形零件表观致密度和力学性能的影响;进一步提高SiC_(p)质量分数至50%,再次评价了上述基板预热温度对成形性能的影响。结果表明,当SiC_(p)质量分数为30%时,升高基板预热温度可以减少成形零件的孔洞和裂纹,成形零件的表观致密度及力学性能显著提高;当基板预热至400℃时,成形零件表观致密度最高达到97.98%,与此同时极限抗压强度和极限抗拉强度分别为578 MPa和56 MPa;随着SiC_(p)质量分数进一步增加至50%,基板预热温度对成形零件致密化和力学性能的强化效果逐步减弱。本研究证明高温预热基板能够有效抑制激光选区熔化成形中等体积分数SiC_(p)/Al复合材料的冶金缺陷,为增材制造SiC_(p)/Al复合材料提供了工程应用解决方案。 展开更多
关键词 中等体积分数 SiC_(p)/Al复合材料 激光选区熔化 基板预热 致密度 力学性能
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Shock-induced chemical reaction characteristics of PTFE-Al-Bi_(2)O_(3)reactive materials
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作者 Chunlan Jiang Rong Hu +2 位作者 Jingbo Zhang Zaicheng Wang Liang Mao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第6期1-12,共12页
A ternary system of PTFE/Al/Bi_(2)O_(3)is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive material.The effects of Bi_(2)O_(3)in the PT... A ternary system of PTFE/Al/Bi_(2)O_(3)is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive material.The effects of Bi_(2)O_(3)in the PTFE/Al/Bi_(2)O_(3)on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry,adiabatic oxygen bomb test and split Hopkinson pressure bar test.The microstructure observed through scanning electron microscope and Xray diffraction results are used to analyze the ignition and reaction mechanism of PTFE/Al/Bi_(2)O_(3).The results indicate that the PTFE/Al/Bi_(2)O_(3)are capable of triggering the exothermic reaction of molten PTFE/Bi_(2)O_(3)and Al/Bi_(2)O_(3)over the PTFE/Al reactive materials,thereby promoting reactions.The excessive aluminum in the ternary system is beneficial for increasing energy release.The ignition of shock-induced chemical reactions in PTFE/Al/Bi_(2)O_(3)is closely related to the material fracture.The dominant mechanism for hot-spot generation under Split Hopkinson Pressure Bar test is the frictional temperature rise at the microcrack after failure. 展开更多
关键词 PTFE/Al/Bi_(2)O_(3) Shock-induced chemical reaction Energy release
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ALS模拟人融合情景模拟教学在重症医学实训教学中的应用
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作者 徐海燕 江鑫 +2 位作者 汪梦瑶 程光宇 邓宇 《江西中医药大学学报》 2023年第3期107-109,124,共4页
目的:评价ALS模拟人融合病案情景模拟教学法在急重症医学实训教学中的应用效果。方法:选择江西中医药大学2017级中医专业本科实习生80名,分为实训组和对照组,各40名。实训组接受病案情景模拟教学法,并且以ALS模拟人为实训技术操作对象... 目的:评价ALS模拟人融合病案情景模拟教学法在急重症医学实训教学中的应用效果。方法:选择江西中医药大学2017级中医专业本科实习生80名,分为实训组和对照组,各40名。实训组接受病案情景模拟教学法,并且以ALS模拟人为实训技术操作对象进行实训教学;对照组接受常规教学模式。评价2组学生的理论成绩、综合救治能力和学生对教学模式满意度等指标。结果:教学后,实训组学生理论考试成绩、急救处理能力、临床分析能力等方面均优于对照组,在团队协作、自主学习及加深理论知识理解等方面满意度高于对照组,两者比较,差异有统计学意义(P<0.01)。结论:ALS模拟人融合病案情景模拟教学可提高医学生在急重症医学的学习效果和综合救治能力,同时可以调动学生学习的积极性。 展开更多
关键词 病案情景模拟教学法 急重症医学 als模拟人 实训教学
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Natural forest ALS-TLS point cloud data registration without control points 被引量:1
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作者 Jianpeng Zhang Jinliang Wang +3 位作者 Feng Cheng Weifeng Ma Qianwei Liu Guangjie Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期809-820,共12页
Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information belo... Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information below the forest canopy due to the occlusion of trees in natural forests.In contrast,TLS is unable to gather fi ne structure information about the upper canopy.To address the problem of incomplete acquisition of natural forest point cloud data by ALS and TLS on a single platform,this study proposes data registration without control points.The ALS and TLS original data were cropped according to sample plot size,and the ALS point cloud data was converted into relative coordinates with the center of the cropped data as the origin.The same feature point pairs of the ALS and TLS point cloud data were then selected to register the point cloud data.The initial registered point cloud data was fi nely and optimally registered via the iterative closest point(ICP)algorithm.The results show that the proposed method achieved highprecision registration of ALS and TLS point cloud data from two natural forest plots of Pinus yunnanensis Franch.and Picea asperata Mast.which included diff erent species and environments.An average registration accuracy of 0.06 m and 0.09 m were obtained for P.yunnanensis and P.asperata,respectively. 展开更多
关键词 Airborne laser scanning(als) Terrestrial laser scanning(TLS) REGISTRATION Natural forest Iterative closest point(ICP)algorithm
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汽车零部件的辐射发射-ALSE法能力验证研究 被引量:1
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作者 张宁 陈宇军 +3 位作者 郭锦添 王珊珊 邵华东 邱添权 《环境技术》 2023年第12期73-77,共5页
能力验证是按照预先设定的准则,利用实验室间比对,评价实验室试验能力的重要外部质量评价活动。本文围绕汽车零部件的辐射发射试验-ALSE法能力验证计划,就相关问题进行探讨,旨在识别实验室间存在的差异,提高实验室间检测数据的再现性和... 能力验证是按照预先设定的准则,利用实验室间比对,评价实验室试验能力的重要外部质量评价活动。本文围绕汽车零部件的辐射发射试验-ALSE法能力验证计划,就相关问题进行探讨,旨在识别实验室间存在的差异,提高实验室间检测数据的再现性和互认度,促进实验室技术能力的提升。 展开更多
关键词 能力验证 汽车零部件 发射 alsE
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ALS抑制类除草剂对西瓜子叶外植体分化的研究
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作者 万丽丽 王转茸 +6 位作者 汤谧 曾红霞 张学军 张娜 任俭 孙玉宏 朱志坤 《湖北农业科学》 2023年第11期202-206,213,共6页
以西瓜自交系D66的子叶为外植体,将外植体置于含有不同浓度乙酰乳酸合成酶(Acetolactate synthase,ALS)抑制剂类除草剂(SU除草剂、IMI除草剂)的筛选培养基上,根据外植体的分化率确定最适宜的除草剂浓度。探讨不同植物生长调节剂(6-BA、N... 以西瓜自交系D66的子叶为外植体,将外植体置于含有不同浓度乙酰乳酸合成酶(Acetolactate synthase,ALS)抑制剂类除草剂(SU除草剂、IMI除草剂)的筛选培养基上,根据外植体的分化率确定最适宜的除草剂浓度。探讨不同植物生长调节剂(6-BA、NAA)浓度配比对不定芽的增殖作用。结果表明,SU除草剂中苯磺隆和噻吩磺隆的最适宜浓度均为0.25 mg/L,苄嘧磺隆的最适宜浓度为0.50 mg/L;IMI除草剂中灭草喹和灭草烟的最适宜浓度均为1.50 mg/L;在MS+1.0 mg/L 6-BA+0.5 mg/L NAA培养基中不定芽的增殖率最高,为287.0%;根据西瓜自交系材料D66确定的除草剂最适宜浓度同样适用于西瓜杂交种(武农8号、黑美人、甜王1号、早佳8424)子叶外植体的筛选试验。 展开更多
关键词 子叶外植体 als抑制类除草剂 西瓜自交系 西瓜杂交种 不定芽增殖 SU除草剂 IMI除草剂
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Integrated Computational Materials Engineering for the Development and Design of High Modulus Al Alloys
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作者 Chengpeng Xue Xinghai Yang +1 位作者 Shuo Wang Junsheng Wang 《Journal of Beijing Institute of Technology》 EI CAS 2023年第4期443-462,共20页
Integrated computational materials engineering(ICME)is to integrate multi-scale computational simulations and key experimental methods such as macroscopic,mesoscopic,and microscopic into the whole process of Al alloys... Integrated computational materials engineering(ICME)is to integrate multi-scale computational simulations and key experimental methods such as macroscopic,mesoscopic,and microscopic into the whole process of Al alloys design and development,which enables the design and development of Al alloys to upgrade from traditional empirical to the integration of compositionprocess-structure-mechanical property,thus greatly accelerating its development speed and reducing its development cost.This study combines calculation of phase diagram(CALPHAD),Finite element calculations,first principle calculations,and microstructure characterization methods to predict and regulate the formation and structure of composite precipitates from the design of highmodulus Al alloy compositions and optimize the casting process parameters to inhibit the formation of micropore defects in the casting process,and the final tensile strength of Al alloys reaches420 MPa and Young's modulus reaches more than 88 GPa,which achieves the design goal of the high strength and modulus Al alloys,and establishes a new mode of the design and development of the strength/modulus Al alloys. 展开更多
关键词 integrated computational materials engineering(ICME) high modulus Al alloys
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Improving the Reading Skills of ALS Learners Through Project RICE(Reading Intervention and Comprehension Enhancement)
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作者 Aimee Rose A.Tenorio 《Journal of Contemporary Educational Research》 2023年第10期10-18,共9页
One of the major problems in the education sector is the reading skills of learners.Students enrolled in the Alternative Learning System(ALS)also experienced this scenario due to several circumstances.This study focus... One of the major problems in the education sector is the reading skills of learners.Students enrolled in the Alternative Learning System(ALS)also experienced this scenario due to several circumstances.This study focused on the improvement of reading comprehension skills of ALS learners by means of project RICE(Reading Intervention and Comprehension Enhancement)as well as the issues and challenges.A quasi-experimental design was utilized in this study which was participated by 54 learners,composed of 27 learners under the experimental group and 27 under the control group.The result revealed that the learners in the experimental group changed from frustration level to instructional level after the implementation of project RICE while the learners in the control group changed from instructional level to inde-pendent level,thereby signifying a significant difference and the effectiveness of the project.Additionally,issues with time and resources were often encountered by the learners. 展开更多
关键词 IMPROVING Reading skills INTERVENTION COMPREHENSION ENHANCEMENT als
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新型乙酰乳酸合成酶(ALS)抑制剂作用机理的研究进展 被引量:11
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作者 郑培忠 沈健英 《杂草科学》 2009年第3期1-5,6,共6页
ALS抑制剂类除草剂具有活性高、选择性强、对哺乳动物安全等优异特点,因而倍受各国政府、工农业界、学术界以及公众的关注。本文通过对ALS抑制剂及其致毒机制的理论研究,对ALS抑制剂的作用机理做了详细的阐述,力求反映ALS抑制剂的最新... ALS抑制剂类除草剂具有活性高、选择性强、对哺乳动物安全等优异特点,因而倍受各国政府、工农业界、学术界以及公众的关注。本文通过对ALS抑制剂及其致毒机制的理论研究,对ALS抑制剂的作用机理做了详细的阐述,力求反映ALS抑制剂的最新研究进展和发展动态,为进一步推动ALS抑制剂的发展及ALS相关基因功能的研究提供理论支持。 展开更多
关键词 乙酰乳酸合成酶(als) als抑制剂 复合物 作用机理 模式
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低压铸造冷却速度对汽车用AlSi7Cu合金组织的影响 被引量:1
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作者 吕欣蕊 李莎莎 +1 位作者 王磊 于丽丽 《热加工工艺》 北大核心 2023年第15期80-82,85,共4页
采用不同的涂料厚度和砂型对汽车用低压铸造Al Si7Cu铝合金试件进行了实际生产,并对其微观组织的枝晶臂长度进行测量,用来评估凝固速度以及冷却速度对合金组织的影响。结果表明:在铝合金低压铸造过程中,随着模具保温涂料厚度的增加,铸... 采用不同的涂料厚度和砂型对汽车用低压铸造Al Si7Cu铝合金试件进行了实际生产,并对其微观组织的枝晶臂长度进行测量,用来评估凝固速度以及冷却速度对合金组织的影响。结果表明:在铝合金低压铸造过程中,随着模具保温涂料厚度的增加,铸型温度能够达到的最大值越低,铸件的温度则越大。通过对低压金属型铸造和砂型铸造的微观组织观察和二次枝晶臂间距测量发现,随着金属型涂料厚度的增加,铸件边部和心部的二次枝晶臂间距均逐渐增大。涂料厚度越大,铸件冷却速度越低;砂型铸造的试样由边部到心部,二次枝晶臂间距由小变大,有机砂型试样的二次枝晶臂间距大于无机砂型试样的,无机砂的传热更快,拥有更大的冷却速率。 展开更多
关键词 低压铸造 Al Si7Cu铝合金 微观组织 冷却速度
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Effect of melt-to-solid volume ratio and preheating temperature on Mg/Al bimetals interface by centrifugal casting 被引量:2
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作者 Morteza Sarvari Mehdi Divandari +1 位作者 Hassan Saghafan Sina Ghaemi Khiavi 《China Foundry》 SCIE CAS CSCD 2023年第3期234-240,共7页
Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and solid.The centrifugal casting process,a type of compound casting,was applied to cast Al... Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and solid.The centrifugal casting process,a type of compound casting,was applied to cast Al/Mg dissimilar bimetals.Magnesium melt was poured at 700 °C,with melt-to-solid volume ratios(Vm/Vs) of 1.5 and 3,into a preheated hollow aluminum cylinder.The preheating temperatures of the solid part were 320,400,and 450 °C,and the constant rotational speed was 1,600 rpm.The cast parts were kept inside the casting machine until reaching the cooling temperature of 150 °C.The result showed that an increase in preheating temperature from 320 to 450 °C led to an enhanced reaction layer thickness.In addition,an increase in the Vm/Vs from 1.5 to 3 resulted in raising the interface thickness from 1.2 to 1.8 mm.Moreover,the interface was not continuously formed when a Vm/Vs of 3 was selected.In this case,the force of contraction overcame the resultant acting force on the interface.An interface formed at the volume ratio of 1.5 was examined using scanning electron microscopy(SEM) equipped with energy-dispersive X-ray spectroscopy(EDS),and the results demonstrated the formation of Al_(3)Mg_(2),Al_(12)Mg_(17) and(δ+Al_(12)Mg_(17)) eutectic structures in the interface. 展开更多
关键词 compound casting centrifugal casting Mg/Al bimetal preheating temperature melt-to-solid volume ratio INTERFACE
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Tuning energy output of PTFE/Al composite materials through gradient structure 被引量:1
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作者 Yao-feng Mao Qian-qian He +3 位作者 Jian Wang Chuan-hao Xu Jun Wang Fu-de Nie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期134-142,共9页
As a typical energetic composite,polytetrafluoroethylene(PTFE)/aluminum(Al)has been widely applied in explosives,pyrotechnics,and propellants due to its ultra-high energy density and intense exothermic reaction.In thi... As a typical energetic composite,polytetrafluoroethylene(PTFE)/aluminum(Al)has been widely applied in explosives,pyrotechnics,and propellants due to its ultra-high energy density and intense exothermic reaction.In this work,the radial gradient(RG)structure of PTFE/Al cylinders with three different PTFE morphologies(200 nm and 5μm particles and 5μm fiber)and content changes are prepared by 3D printing technology.The effect of radial gradient structure on the pressure output of PTFE/Al has been studied.Compared with the morphology change of PTFE,the change of component content in the gradient structure has an obvious effect on the pressure output of the PTFE/Al cylinder.Furthermore,the relationships of the morphology,content of PTFE and the combustion reaction of the PTFE/Al cylinder reveal that the cylinder shows a more complex flame propagation process than others.These results could provide a strategy to improve the combustion and pressure output of PTFE/Al. 展开更多
关键词 PTFE/Al composite Gradient structure Radial gradient Pressure output
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Effects of Al and Co doping on the structural stability and high temperature cycling performance of LiNi_(0.5)Mn_(1.5)O_(4) spinel cathode materials 被引量:1
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作者 Jianfeng Cheng Meixuan Li +4 位作者 Yutong Wang Jiexiang Li Jiawei Wen Chunxia Wang Guoyong Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期201-209,共9页
The poor structural stability and capacity retention of the high-voltage spinel-type LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)limits their further application.Herein,Al and Co were doped in LNMO materials for a more stable struct... The poor structural stability and capacity retention of the high-voltage spinel-type LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)limits their further application.Herein,Al and Co were doped in LNMO materials for a more stable structure and capacity.The LNMO,LiNi_(0.45)Al_(0.05)Mn_(1.5)O_(4)(LNAMO)and LiNi_(0.45)Co_(0.05)Mn_(1.5)O_(4)(LNCMO)were synthesized by calcination at 900℃ for 8 h,which was called as solid-phase method and applied universally in industry.XRD,FT-IR and CV test results showed the synthesized samples have cation disordering Fd-3m space group structures.Moreover,the incorporation of Al and Co increased the cation disordering of LNMO,thereby increasing the transfer rate of Li+.The SEM results showed that the doped samples performed more regular and ortho-octahedral.The EDS elemental analysis confirmed the uniform distribution of each metal element in the samples.Moreover,the doped samples showed better electrochemical properties than undoped LNMO.The LNAMO and LNCMO samples were discharged with specific capacities of 116.3 mA·h·g^(-1)and 122.8 mA·h·g^(-1)at 1 C charge/discharge rate with good capacity retention of 95.8% and 94.8% after 200 cycles at room temperature,respectively.The capacity fading phenomenon of the doped samples at 50℃ and 1 C rate was significantly improved.Further,cations doping also enhanced the rate performance,especially for the LNCMO,the discharge specific capacity of 117.9 mA·h·g^(-1)can be obtained at a rate of 5 C. 展开更多
关键词 High voltage spinel Al/Co doping High temperature cycling stability
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激光粉末床熔融成形Ti6Al4V/AlSi10Mg合金电子束焊接工艺研究
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作者 商乔 宋一诺 +1 位作者 魏连峰 王廷 《电焊机》 2023年第11期9-15,共7页
针对激光粉末床熔融成形的Ti6Al4V合金和AlSi10Mg合金进行电子束对接试验,对比分析不同侧偏束条件下焊接接头的组织和性能。结果表明:钛侧偏束(-0.6 mm)相较于铝侧偏束(+0.6 mm)所获接头的成形更稳定、美观。铝侧偏束时,接头表面出现了... 针对激光粉末床熔融成形的Ti6Al4V合金和AlSi10Mg合金进行电子束对接试验,对比分析不同侧偏束条件下焊接接头的组织和性能。结果表明:钛侧偏束(-0.6 mm)相较于铝侧偏束(+0.6 mm)所获接头的成形更稳定、美观。铝侧偏束时,接头表面出现了大量的气孔及裂纹,接头内部也存在大量的气孔,主要聚集于铝侧熔合线上;钛侧偏束时,接头焊接缺陷的数量明显减少。两种工艺条件下的界面层均形成了一定数量的金属间化合物,铝侧偏束时以TiAl为主,钛侧偏束时形成了TiAl3、TiAl_(2)、Ti_(3)Al和TiAl等多种金属间化合物。铝侧偏束接头抗拉强度最高为81 MPa,钛侧偏束接头抗拉强度最高可达到128 MPa。两种接头均失效于反应界面层处,呈现出脆性断裂的特征。 展开更多
关键词 激光粉末床熔融 Ti/Al异种合金 电子束焊接 微观组织 偏束条件
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