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Asian Agricultural Research 2024年第8期16卷 29-32页

作者： Junxia LUO Qianqian zhao Lumei DUAN Yanzhen LI Huifang QIAO Zhipei DOU jianbo zhao Zhengzhou Product Quality Inspection and Testing Center Zhengzhou 450006China Jiaozuo Product Quality Inspection and Testing Center Kaifeng 454000China Kaifeng Product Quality Inspection and Testing Center Kaifeng 454000China Zhengzhou Agricultural Technology Extension Center Zhengzhou 450002China

[Objectives]To fully understand the quality of commercial enzyme inhibition-colorimetric pesticide residue rapid detection kits,so that they can play a greater role in the detection and supervision of agricultural products.[Methods]The sensitivity of 28 kinds of pesticides was determined by using the commercially available enzyme inhibition colorimetric rapid detection kit with Hendu brand.[Results]There was a significant difference in the sensitivity of the kit to each pesticide,and the kit was more sensitive to dichlorvos among the 28 pesticides *** sensitivity to methyl isosalifos,dimethoate,isocarbophos,fenthion and phorate was poor,and the sensitivity to quinalphos was different between 3.0 and 2.5 mL.[Conclusions]The large difference of the sensitivity of the enzyme inhibition-colorimetric rapid detection kit for pesticide residues to different kits is a reason for the false positive and false negative test results of the kit,which needs to be considered by relevant personnel.

关键词： Enzyme inhibition-colorimetry Reagent kit Pesticide Inhibition rate Sensitivity

基于主成分和体外抗氧化活性的酒萸肉的蒸制研究

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时珍国医国药 2024年第3期35卷 644-647页

作者：杨菁蕾代萌王肇扬乔博灵西北大学教育部西部资源生物与生物技术重点实验室陕西西安710069 陕西省中药创新药物工程技术研究中心陕西西安710069

目的考察酒萸肉炮制中黄酒和蒸制对主成分和抗氧化活性的影响。方法制备蒸制时间为0.5,1,2,3,5和7 h的清蒸和酒蒸山萸肉样品,采用高效液相色谱法,测定没食子酸、5-羟甲基糠醛、莫诺苷、马钱苷、山茱萸新苷I含量;应用主成分分析法,明确... 详细信息

目的考察酒萸肉炮制中黄酒和蒸制对主成分和抗氧化活性的影响。方法制备蒸制时间为0.5,1,2,3,5和7 h的清蒸和酒蒸山萸肉样品,采用高效液相色谱法,测定没食子酸、5-羟甲基糠醛、莫诺苷、马钱苷、山茱萸新苷I含量;应用主成分分析法,明确清蒸和酒蒸的差异;利用DPPH法测定抗氧化活性。结果随蒸制时间的增加,新生成分5-羟甲基糠醛含量明显增加,清蒸高于酒蒸;没食子酸含量明显增加,酒蒸高于清蒸;莫诺苷、马钱苷、山茱萸新苷I含量,在清蒸样品中明显下降,在酒蒸样品中先上升,5 h后开始下降;抗氧化活性,与生萸肉相比,清蒸样品明显下降,酒蒸样品明显上升。结论黄酒在酒萸肉的炮制中具有重要作用,可以促进没食子酸的生成,减缓蒸制导致的主成分含量的下降,增强抗氧化活性,调控5-羟甲基糠醛的生成。

关键词：山萸肉清蒸酒蒸主成分抗氧化活性 5-羟甲基糠醛

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白地黑花瓷黑彩的仿制及呈色研究

中国陶瓷 2024年第10期60卷 68-79页

作者：王芬赵馨怡朱建锋罗宏杰冯篱任肇陕西科技大学材料科学与工程学院西安710021 上海大学文化遗产与信息管理学院上海200444 陕西科技大学设计与艺术学院西安710021

白地黑花瓷是先民创造性以低品位原料生产的一类绘画装饰瓷,在我国北方地区广为烧造,今天仍然有广泛的市场。其中的黑彩,多选自当地的贫铁矿烧成,但外观受多种因素影响。采用考古实验法,通过古瓷样品的测试分析,确定黑彩的组成与施彩工... 详细信息

白地黑花瓷是先民创造性以低品位原料生产的一类绘画装饰瓷,在我国北方地区广为烧造,今天仍然有广泛的市场。其中的黑彩,多选自当地的贫铁矿烧成,但外观受多种因素影响。采用考古实验法,通过古瓷样品的测试分析,确定黑彩的组成与施彩工艺。后选用耀州窑陈炉当地制瓷原料,在电窑中以中性气氛烧成,仿烧了耀州窑白地黑花瓷黑彩;采用X射线荧光光谱仪(XRF)、色度仪、超景深显微镜、X射线衍射仪(XRD)、显微共聚焦激光拉曼光谱仪(Raman)等测试分析探讨了烧成温度、彩料的Fe_(2)O_(3)含量、施釉厚度等黑彩呈色的影响。对比发现,仿烧样品基本达到明代白地黑花瓷黑彩的效果。研究结果有助于深入探讨耀州窑白地黑花瓷的地方特色的形成因素,为进一步认知古代白地黑花瓷的科学内涵及地域特色建立理论与实验基础。

关键词：白地黑花瓷制备工艺耀州窑化学组成呈色机理

钛合金铸锭冒口损失率差异性成因分析及对策研究

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铸造 2024年第7期73卷 962-967页

作者：郑亚波毛玲玲刘钊陈峰陈战乾宝鸡钛业股份有限公司陕西宝鸡721014 宝钛集团有限公司陕西宝鸡721014

VAR熔炼的钛合金铸锭,熔炼末期需要采用补缩工艺制度,降低铸锭冒口损失率,提高成材率。在实际生产过程中,钛合金铸锭冒口损失率受各种因素影响,每个铸锭之间存在较大差异,且波动范围大,损失严重。为了分析钛合金铸锭冒口损失率差异性的... 详细信息

VAR熔炼的钛合金铸锭,熔炼末期需要采用补缩工艺制度,降低铸锭冒口损失率,提高成材率。在实际生产过程中,钛合金铸锭冒口损失率受各种因素影响,每个铸锭之间存在较大差异,且波动范围大,损失严重。为了分析钛合金铸锭冒口损失率差异性的影响因素,应用Minitab统计软件,采用多因子方差分析方法进行研究,找出了熔炼工班次、补缩时间班次、探伤操作者、补缩期操作稳定性、补缩过程是否频繁短路等显著影响因子,排除了不显著的因子交互作用,并针对各显著因子,制定了相应的改进对策,有效降低了钛合金铸锭冒口损失率以及铸锭间的差异性,提高了成品率。

关键词：钛合金铸锭冒口损失率 Minitab 方差分析

Transformer in reinforcement learning for decision-making:a survey

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 763-790页

作者： Weilin YUAN Jiaxing CHEN Shaofei CHEN Dawei FENG Zhenzhen HU Peng LI Weiwei zhao College of Information and Communication National University of Defense TechnologyWuhan 430014China College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410072China Laboratory for Parallel and Distributed Processing National University of Defense TechnologyChangsha 410072China

Reinforcement learning(RL)has become a dominant decision-making paradigm and has achieved notable success in many real-world ***,deep neural networks play a crucial role in unlocking RL’s potential in large-scale decision-making *** by current major success of Transformer in natural language processing and computer vision,numerous bottlenecks have been overcome by combining Transformer with RL for *** paper presents a multiangle systematic survey of various Transformer-based RL(TransRL)models applied in decision-making tasks,including basic models,advanced algorithms,representative implementation instances,typical applications,and known *** work aims to provide insights into problems that inherently arise with the current RL approaches,and examines how we can address them with better TransRL *** our knowledge,we are the first to present a comprehensive review of the recent Transformer research developments in RL for *** hope that this survey provides a comprehensive review of TransRL models and inspires the RL community in its pursuit of future *** keep track of the rapid TransRL developments in the decision-making domains,we summarize the latest papers and their open-source implementations at https://***/williamyuanv0/Transformer-in-Reinforcement-Learning-for-Decision-Making-A-Survey.

关键词： Transformer Reinforcement learning(RL) Decision-making(DM) Deep neural network(DNN) Multi-agent reinforcement learning(MARL) Meta-reinforcement learning(Meta-RL)

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定向断裂控制爆破下层理页岩的致裂机理

爆炸与冲击 2024年第6期44卷 1-15页

作者：杨国梁毕京九董智文赵桐德赵建宇赵康朴中国矿业大学(北京)力学与建筑工程学院北京100083

为探究定向断裂控制爆破下层理页岩的爆破致裂机理,采用切缝药包,对四种切缝角度下的页岩立方体试件进行爆破试验,采用数字图像相关技术(DIC)对页岩试件表面应变场的演化过程进行监测,分析了微裂纹孕育至宏观裂纹贯通的内在机理,并基于... 详细信息

为探究定向断裂控制爆破下层理页岩的爆破致裂机理,采用切缝药包,对四种切缝角度下的页岩立方体试件进行爆破试验,采用数字图像相关技术(DIC)对页岩试件表面应变场的演化过程进行监测,分析了微裂纹孕育至宏观裂纹贯通的内在机理,并基于盒维数理论计算了不同切缝角度下页岩试件表面裂纹的分形维数,采用Matlab软件对爆后块度的筛分方法进行了编程分析,开发了全自动的粒径分析程序,实现了粒径圈定的可视化。试验结果表明:试件在不同比例爆距内的裂纹总密度与比例爆距之间存在负相关的幂函数关系,切缝方向与层理弱面的夹角对微观损伤区域出现的位置影响显著,当层理弱面与切缝方向平行时,损伤区域多集中于层理弱面处,对宏观裂纹的扩展路径影响显著,易于形成单一裂纹;层理弱面处的能量泄漏是造成页岩爆破破碎效果较差的重要因素,当切缝方向与层理弱面一致时,试件爆后的大块占比较高,爆后块度的分形维数平均值在各组间最低,仅为0.7843,而当切缝方向与层理面垂直时,试件的爆后块度分布较为均匀,爆后块度的分形维数平均值达到了2.5233,爆破破碎效果相对较好。

关键词：页岩爆破裂隙场数字图像相关技术块度筛分程序分形维数

Optimum weighting-coefficient-pair in inter-carrier interference self-cancellation scheme of OFDM system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1676-1684页

作者： Min-jian zhao Di ZHANG Bin CAI Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

As one of the most important components of the wideband wireless access technique, orthogonal frequency division multiplexing （OFDM） has a high usage rate of spectrum and combats inter-symbol interference （ISI） in multi-path fading channel. However, when there are frequency offsets during the signal transmission, the inter-carrier interference （ICI） is introduced, which significantly degrades the performance. The existing ICI self-cancellation schemes such as PCC-OFDM are not optimum to minimize the interference considering both noise and ICI. In this paper, a new metric named S1NR （signal-to-interference- and-noise ratio） is proposed. We discuss the optimization issue when a constant frequency offset exists and in time-varying channels. The optimum weighting-coefficient-pair （OWCP） is obtained, which maximizes SINR theoretically through the alternant iteration algorithm. Simulations show that the performance of OWCP-OFDM is better than that of PCC-OFDM, especially when the frequency offset is large. Although the ICI self-cancellation scheme suffers bandwidth inefficiency, from the simulation results we can also see that the performance of OWCP-OFDM is much better than that of the standard OFDM systems with the same bandwidth efficiency when a frequency offset exists. Moreover, since the redundant modulation provides the capability to suppress ICI as well as a receiving SNR gain, it can be considered as exchanging the bandwidth for SNR.

关键词： Orthogonal frequency division multiplexing (OFDM) Frequency offset Inter-carrier interference (ICI) Polynomial cancellation coding (PCC) Optimum weighting-coefficient-pair (OWCP)

The Fang’s hypoglycemic formula improves insulin resistance in type 2 diabetes mellitus by regulating mitochondrial autophagy

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Integrative Medicine Discovery 2024年第16期8卷 1-7页

作者： Jia Zhu Xu-Dong Chen Jie zhao Department of Respiratory Jiaxing Hospital of Traditional Chinese MedicineJiaxing 314001China Department of Endocrinology Jiaxing Hospital of Traditional Chinese MedicineJiaxing 314001China Department of Endocrinology The First Affiliated Hospital of Yunnan University of Chinese MedicineKunming 650500China

Background:To investigate the pharmacological effects of Fangshi jiangtang decoction(FSJT)on type 2 diabetes mellitus(T2DM)model rats and explore its mechanism of action from the perspective of mitochondrial ***:Sixty Sprague Dawley rats were randomly divided into six groups after one week of adaptive feeding:Control group,T2DM model group,metformin group(0.2 g/kg by gavage),and FSJT low,medium,and high dose groups(9.5,19,38 g/kg by gavage).Except for the Control group,the other five groups were given a high-fat *** treatment lasted for 8 weeks,and blood glucose levels were measured *** weeks later,blood samples were collected from the rats,and serum was separated for the determination of HbA1c,oral glucose tolerance test,and homeostatic model assessment for insulin resistance *** pancreas of the rats was collected,weighed,and *** same part of the pancreas was used for *** were used to detect triglycerides,total cholesterol,interleukin-1β,interleukin-6,tumor necrosis factor-α,malondialdehyde,glutathione peroxidase,and superoxide dismutase in pancreatic tissue to assess the effects of FSJT on inflammation and oxidative stress in T2DM *** blot analysis was performed to detect the expression of VDAC1,TOM20,COXⅣ,PINK1,Parkin,beclin1,light chain 3,and selective autophagy adaptor protein P62 to evaluate the effects of FSJT on mitochondrial autophagy in T2DM model ***:Compared with the T2DM model group,FSJT intervention significantly reduced blood glucose,HbA1c,oral glucose tolerance test,and homeostatic model assessment for insulin resistance index in T2DM model rats,alleviated pancreatic tissue lesions,reduced levels of total cholesterol,triglycerides,interleukin-1β,interleukin-6,tumor necrosis factor-α,and malondialdehyde,increased glutathione peroxidase and superoxide dismutase activities,downregulated the expression of VDAC1,TOM20,COXⅣ,and P62 proteins,and upregulated the expression of PINK1,

关键词： Fangshi jiangtang decoction type 2 diabetes mellitus mitochondrial autophagy oxidative stress

基于分期播种试验夏玉米延迟收获促进子粒灌浆和粒重增益效应

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玉米科学 2024年第4期32卷 55-64,76页

作者：赵花荣任三学张玲田晓丽中国气象科学研究院北京100081 河北固城农业气象国家野外科学观测研究站河北保定072656 中国气象局/河南省农业气象保障与应用技术重点开放实验室郑州450003 甘肃省气象局信息与装备保障中心兰州730020

基于2019-2022年夏玉米播期试验资料,分析夏玉米生理成熟后延迟收获对子粒农艺性状改善、增产效应。结果表明,早播10 d至晚播20 d处理的有效灌浆结束日均比生理成熟期延后,子粒有效灌浆持续日数依次比其花后10 d至生理成熟期日数延长28~... 详细信息

基于2019-2022年夏玉米播期试验资料,分析夏玉米生理成熟后延迟收获对子粒农艺性状改善、增产效应。结果表明,早播10 d至晚播20 d处理的有效灌浆结束日均比生理成熟期延后,子粒有效灌浆持续日数依次比其花后10 d至生理成熟期日数延长28~9 d,播期每推迟10 d延长日数减少6.3 d。子粒农艺性状有明显的改善,百粒重、穗粒重提高,子粒增产效应明显,理论产量增产率16.95%~7.66%,增产量1960.36~681.51 kg/hm^(2),对照增产最多,比晚播10、20 d增产粮食多2.4~2.9倍。为华北地区提高气候资源利用效率和粮食生产提质增效提供参考。

关键词：夏玉米延迟收获子粒灌浆增产效率气候变化

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航空发动机主轴轴承剥落扩展试验

航空发动机 2024年第1期50卷 124-128页

作者：胡铭鑫孔令成赵聪张浩毛宏图中国航发沈阳发动机研究所沈阳110015 中国航发航空发动机动力传输重点实验室沈阳110015

为探索轴承的剥落极限,开展了航空发动机主轴轴承的剥落扩展试验研究。介绍了轴承损伤的形式以及国内外关于疲劳剥落损伤的研究现状;介绍了试验轴承的初始剥落状态以及试验器的基本情况,明确了轴承的润滑条件和监测方式;按照发动机的真... 详细信息

为探索轴承的剥落极限,开展了航空发动机主轴轴承的剥落扩展试验研究。介绍了轴承损伤的形式以及国内外关于疲劳剥落损伤的研究现状;介绍了试验轴承的初始剥落状态以及试验器的基本情况,明确了轴承的润滑条件和监测方式;按照发动机的真实工况和载荷谱制定试验方案并开展试验,定期分解监控轴承的剥落扩展趋势;对试验过程中金属屑末质量分数、轴承温度以及转子振动的监测结果进行了分析。结果表明:小面积剥落的轴承在18 h试验时间内仍能继续工作,轴承温升未发生明显改变,轴承外圈温度大部分时间内保持在150~190℃,但金属屑末质量分数及转子振动时域幅值不断增大,金属屑末累计增长约9500个,振动时域幅值已超过600g。各项参数的监测结果对发动机地面试车或飞行具有重要的参考价值。

关键词：航空发动机主轴轴承剥落扩展试验研究监测方式