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Synthesis of tetrahydroisoquinolines through TiCl4-mediated cyclization and Et3SiH reduction

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Chinese Chemical Letters 2020年第3期31卷 729-732页

作者： Zeyu Shi Qiong Xiao dali Yin State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China Department of Medicinal Chemistry Beijing Key Laboratory of Active Substances Discovery and Drugability EvaluationInstitute of Materia MedicaPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100050China

A versatile and efficient telescoped reaction sequence for the synthesis of tetrahydroisoquinolines(THIQs)is reported that uses TiCl4 to promote cyclization of a benzylaminoacetal derivative and Et3SiH for reduction of the intermediate *** method is complimentary to the classical Pomeranz-Fritsch and related reactions since it tolerates electron-withdrawing substituents and allows access to 8-substituted THIQs.

关键词： Tetrahydroisoquinoline TiCl4 Cyclization Et3SiH Telescoped reaction

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新型铝合金MIG焊接头微观组织与力学性能

焊接学报 2024年第7期45卷 74-82页

作者：金聪聪黄立兵黄文彬王大力马月婷李鹏董红刚大连理工大学材料科学与工程学院大连116024 空军装备部驻沈阳地区第四军事代表室沈阳110023

随着船舶轻量化和快速化的发展,以铝代钢成为未来船舶制造的必然趋势.对一种1. mm厚新型铝合金进行单面MIG焊工艺试验,研究两层三道焊和三层四道焊对接头综合性能的影响规律.结果表明,焊缝上表面和下表面宏观形貌均较好,都有α-Al、Al6(... 详细信息

随着船舶轻量化和快速化的发展,以铝代钢成为未来船舶制造的必然趋势.对一种1. mm厚新型铝合金进行单面MIG焊工艺试验,研究两层三道焊和三层四道焊对接头综合性能的影响规律.结果表明,焊缝上表面和下表面宏观形貌均较好,都有α-Al、Al6(Fe,Mn)和Mg2Si相;在靠近熔合线的热影响区中有尺寸较大的等轴晶生成,焊缝边缘沿垂直于熔合线方向生成柱状晶,焊缝中心为树枝晶,且每层焊缝晶粒尺寸不同,前层焊缝晶粒尺寸小于后层焊缝晶粒尺寸;Fe和Mn元素在热影响区发生偏聚,形成Al6(Fe,Mn)相,Mg元素倾向于沿焊缝晶界或分布在焊缝组织中以平衡相的形式析出.1.接头平均抗拉强度为294 MPa,达到母材抗拉强度的78.4%,断后伸长率为6.56%,2号接头平均抗拉强度为350 MPa,达到母材抗拉强度的93.3%,断后伸长率为1..3%;接头硬度整体表现为焊缝区最低,热影响区次之,母材最高,同时多层多道焊的每层焊缝硬度与焊接顺序有关,第一层焊缝硬度最大.

关键词：熔化极气体保护焊多层多道焊韧性断裂硬度

Minimax entropy-based co-training for fault diagnosis of blast furnace

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中国化学工程学报:英文版 2023年第7期59卷 231-239页

作者： dali Gao Chunjie Yang Bo Yang Yu Chen Ruilong Deng The State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Jianwei Digital Sphere Co. LtdLianyungang 222113China Jiangsu Binxin Iron and Steel Group Co. LtdChongqing 401220China

Due to the problems of few fault samples and large data fluctuations in the blast furnace(BF)ironmaking process,some transfer learning-based fault diagnosis methods are *** vast majority of such methods perform distribution adaptation by reducing the distance between data distributions and applying a classifier to generate pseudo-labels for ***,since the training data is dominated by labeled source domain data,such classifiers tend to be weak classifiers in the target *** addition,the features generated after domain adaptation are likely to be at the decision boundary,resulting in a loss of classification ***,we propose a novel method called minimax entropy-based co-training(MMEC)that adversarially optimizes a transferable fault diagnosis model for the *** structure of MMEC includes a dual-view feature extractor,followed by two classifiers that compute the feature's cosine similarity to representative vector of each *** transfer is achieved by alternately increasing and decreasing the entropy of unlabeled target samples with the classifier and the feature extractor,*** BF fault diagnosis experiments show that our method improves accuracy by about 5%over state-of-the-art methods.

关键词： Co-training Fault diagnosis Blast furnace Minimax entropy Transfer learning

The productivity of two serial chemostats

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生物数学学报:英文版 2023年第6期16卷 57-111页

作者： Manel dali-Youcef Tewfik Sari MISTEA L'institut Agro Montpellier INRAEUniversite Montpellier2 Place Pierra Viala F-34060 Montpellier Cedec 2France ITAP L'Institut Agro MontpellierINRAE UniversitéMontpellier361 rue Jean-Francois Breton BP 5095F-34196 Montpellier Cedea 5France

This paper considers the production of biomass of two interconnected chemostats in series with biomass mortality and a growth kinetic of the biomass described by an increasing function.A comparison is made with the productivity of a single chemostat with the same mortality rate and with volume equal to the sum of the volumes of the two *** determine the operating conditions under which the productivity of the serial configuration is greater than the productivity of the single ***,the differences and similarities in the results corresponding to the case with mortality and the one without mortality,are *** mortality leads to surprising results where the productivity of a steady state where the bacteria are washed out in the first chemostat is greater than the one where the bacteria are present in both chemostats.

关键词： Chemostat gradostat mortality bifurcations global stability operating diagram biomass productivity

高血压脑出血常规开颅手术与微创钻孔引流术的疗效对比

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系统医学 2024年第11期9卷 113-115,119页

作者：郑达理王珊孔维锋汶上县人民医院神经外科山东济宁272000 汶上县人民医院检验科山东济宁272000

目的分析高血压脑出血(Hypertensive Cerebral Hemorrhage, HICH)治疗中选择常规开颅手术与微创钻孔引流术的价值。方法选取汶上县人民医院于2021.1.—2023年6月收治的82例HICH患者为研究对象,依据随机数表法分为两组,每组41.。对... 详细信息

目的分析高血压脑出血(Hypertensive Cerebral Hemorrhage, HICH)治疗中选择常规开颅手术与微创钻孔引流术的价值。方法选取汶上县人民医院于2021.1.—2023年6月收治的82例HICH患者为研究对象,依据随机数表法分为两组,每组41.。对照组采用常规开颅手术治疗,观察组采用微创钻孔引流术治疗。对比两组的手术、预后情况、并发症发生率。结果观察组的手术指标和预后指标优于对照组,差异有统计学意义(P均1.%)低于对照组(58.54%),差异有统计学意义(χ^(2)=4.904,P<0.05)。结论为高血压脑出血患者提供微创钻孔引流术可减轻神经损伤程度,亦可缩短治疗及康复时间,提升整体疗效。

关键词：高血压脑出血常规开颅手术微创钻孔引流术

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低氮胁迫相关microRNA的研究进展

植物生理学报 2024年第1期60卷 1-8页

作者：刘欣雨王皓李佳佳徐翎清兴旺刘大丽鲁振强黑龙江大学生命科学学院黑龙江省寒区植物基因与生物发酵重点实验室哈尔滨150080 黑龙江大学国家甜菜种质中期库哈尔滨150080 黑龙江省高等学校甜菜遗传育种重点实验室黑龙江大学现代农业与生态环境学院哈尔滨150080

microRNA是一类小的内源性的非编码RNA,在生命有机体抵御不良环境中发挥着重要作用。氮是植物生长发育必不可少的元素,广泛参与到各种生理反应中。氮肥的施用虽然在一定程度上增加了植物的生物量,但过多的氮肥也带来了严重的环境问题,... 详细信息

microRNA是一类小的内源性的非编码RNA,在生命有机体抵御不良环境中发挥着重要作用。氮是植物生长发育必不可少的元素,广泛参与到各种生理反应中。氮肥的施用虽然在一定程度上增加了植物的生物量,但过多的氮肥也带来了严重的环境问题,探索植物的氮代谢及氮高效利用的分子机理成为当务之急。研究表明,microRNA能够受到氮素水平的调控,并可产生相应的应答机制以维持植物的生长需求。因此,本文综述了植物对氮素的利用现状、microRNA对低氮胁迫的响应以及microRNA参与氮代谢的最新研究进展,重点探讨了miR1.6、mi R31.、miR1.7和miR408等在调控氮素相关的植物表型、激素、初级和次级代谢过程中的作用,为进一步利用microRNA开展氮高效生物育种奠定基础。

关键词： microRNA 氮代谢低氮氮效率

NEW NONSTANDARD JOB SHOP SCHEDULING ALGORITHM

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Chinese Journal of Mechanical Engineering 2008年第4期21卷 97-100页

作者： XIE Zhiqiang YE Guangjie ZHANG dali TAN Guangyu School of Computer Science and Technology Harbin University of Science and Technology Harbin 150080 China Department of Mathematics and Statistics University of Calgary Calgary T2N 1N4 Canada School of Mechanical Power Engineering Harbin University of Science and Technology Harbin 150080 China

Considering the complex constraint between operations in nonstandard job shop scheduling problem （NJSSP）, critical path of job manufacturing tree is determined according to priority scheduling function constructed. Operations are divided into dependent operations and independent operations with the idea of subsection, and corresponding scheduling strategy is put forward according to operation characteristic in the segment and the complementarities of identical function machines. Forward greedy rule is adopted mainly for dependent operations to make operations arranged in the right position of machine selected, then each operation can be processed as early as possible, and the total processing time of job can be shortened as much as possible. For independent operations optimum scheduling rule is adopted mainly, the inserting position of operations will be determined according to the gap that the processing time of operations is subtracted from idle time of machine, and the operation will be inserted in the position with minimal gap. Experiments show, under the same conditions, the result that operations are scheduled according to the object function constructed, and the scheduling strategy adopted is better than the result that operations are scheduled according to efficiency scheduling algorithm.

关键词： Nonstandard job shop scheduling Priority scheduling function Subsection Forward greedy rule Optimum scheduling rule

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新文科:观念误区及建设路径

南京理工大学学报（社会科学版） 2024年第5期37卷 71-77,85页

作者：罗向阳高大力陈建有西北工业大学马克思主义学院陕西西安710072 西北工业大学出版社陕西西安710072 西北工业大学党政办公室陕西西安710072

新文科建设在较短时间内取得了长足进展,但关于新文科的观念误区仍然存在。以人工智能(AI)为代表的科技革命带来的社会变革对文科发展提出了新的要求,更加凸显了传统文科人才培养“疏离现实”、传统文科学术研究“依附西方”、传统文科... 详细信息

新文科建设在较短时间内取得了长足进展,但关于新文科的观念误区仍然存在。以人工智能(AI)为代表的科技革命带来的社会变革对文科发展提出了新的要求,更加凸显了传统文科人才培养“疏离现实”、传统文科学术研究“依附西方”、传统文科学科建设“画地为牢”问题的严重性。新文科建设要优化文科人才培养体系、提升文科学术研究自主性、用好学科交叉融合的“催化剂”。

关键词：新文科传统文科人工智能自主性学科交叉融合

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高强度玻璃纤维对阻燃增强PET性能的影响

现代塑料加工应用 2024年第2期36卷 21-24页

作者：蔡涛康鹏辛琦赵航娄硕高达利中石化(北京)化工研究院有限公司北京100013

研究了高强度玻璃纤维对阻燃增强聚对苯二甲酸乙二酯(PET)材料性能的影响,并制备了综合性能优良的高性能阻燃增强PET材料,同时分析了高强度玻璃纤维和普通无碱玻璃纤维在PET材料中的尺寸分布。结果表明:高强度玻璃纤维的表面处理可以有... 详细信息

研究了高强度玻璃纤维对阻燃增强聚对苯二甲酸乙二酯(PET)材料性能的影响,并制备了综合性能优良的高性能阻燃增强PET材料,同时分析了高强度玻璃纤维和普通无碱玻璃纤维在PET材料中的尺寸分布。结果表明:高强度玻璃纤维的表面处理可以有效提高阻燃增强PET材料的性能;阻燃增强PET的性能随着玻璃纤维含量的增加而提高,高强度玻璃纤维比普通无碱玻璃纤维能更好地改善PET材料的综合性能。

关键词：高强度玻璃纤维阻燃增强聚对苯二甲酸乙二酯