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基于数控刀具选择的数控加工工艺影响分析

机电产品开发与创新 2024年第4期37卷 146-148页

作者：王延佳左峰赵江王联翔张宗芳北方自动控制技术研究所山西太原030006

在现代制造业飞速发展过程中,数控技术在很多领域的应用日益增多。数控加工技术主要表现出精度高、效率高以及自动化程度高等特点,为促进现代制造业发展提供了重要技术支撑。数控刀具选择是数控加工中的重要内容,包括铣刀、车刀、钻头... 详细信息

在现代制造业飞速发展过程中,数控技术在很多领域的应用日益增多。数控加工技术主要表现出精度高、效率高以及自动化程度高等特点,为促进现代制造业发展提供了重要技术支撑。数控刀具选择是数控加工中的重要内容,包括铣刀、车刀、钻头、铰刀、丝锥等常见刀具,需要保证数控刀具的合理选择,才能提高数控加工的效率与质量。本文将简述数控刀具的基本概念和分类,然后概述了数控刀具选择的原则和方法,最后对数控刀具选择对数控加工工艺的影响进行分析。

关键词：数控刀具数控加工数控机床

Time-like Linear Weingarten Surfaces in Lorentzian Space Forms

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1021-1026页

作者： Da feng zuo Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China Department of Mathematics University of Science and Technology of China Anhui 230026 P. R. China

In this paper we study Backlund transformations of time-like linear Weingarten surfaces with negative discriminant in Lorentzian space forms.

关键词： Time-like linear Weingarten surfaces Backlund transformations Lorentzian space forms

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基于近红外光谱技术对绿豆产地溯源的研究

黑龙江八一农垦大学学报 2024年第1期36卷 49-54页

作者：陈明明邱彦超宋妍杨斯琪左锋钱丽丽黑龙江八一农垦大学食品学院大庆163319 国家杂粮工程技术研究中心黑龙江省农产品加工与质量安全重点实验室

为探索绿豆产地鉴别可行性,实现对来自白城、杜尔伯特、泰来、泗水绿豆原产地的快速鉴别。研究运用近红外光谱技术,并结合PLS-DA法(偏最小二乘判别分析)进行建模,对4个产地的120份绿豆粉末样品进行近红外光谱的扫描,分别采用不同光谱预... 详细信息

为探索绿豆产地鉴别可行性,实现对来自白城、杜尔伯特、泰来、泗水绿豆原产地的快速鉴别。研究运用近红外光谱技术,并结合PLS-DA法(偏最小二乘判别分析)进行建模,对4个产地的120份绿豆粉末样品进行近红外光谱的扫描,分别采用不同光谱预处理方法[标准正态变换(SNV)、多元散射校正(MSC)、矢量归一化与导数处理等]最终确定矢量归一化+MSC建立的模型最稳定,建模波长为12 000~4 000 cm-1全波长。主成分分析提取3个有效主成分(主成分1贡献率为52.44%,主成分2贡献率为30.16%,主成分3贡献率为9.57%),其累计贡献率达到92.17%。用预测样本集进行模型的验证,白城、杜尔伯特、泰来、泗水4个产地的预测正确率分别为100%、80%、80%和100%。预测结果达到80%以上,初步认定近红外光谱分析技术可用于绿豆产地溯源研究。

关键词：绿豆产地鉴别近红外光谱主成分分析偏最小二乘判别分析

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基于分频段原理的风电机组一次调频控制策略

节能技术 2024年第4期42卷 362-367页

作者：姚瑶王瑛玮左峰江海洋王智超王琦郭钰锋国网黑龙江省电力有限公司黑龙江哈尔滨150001 哈尔滨工业大学电气工程及自动化学院黑龙江哈尔滨150001

随着风光发电占比逐渐增加,若其未有效参与调频或调频方式不当,系统在频率偏差维持方面将面临较大挑战,频率稳定性成为制约风电渗透率提升的关键因素。为了应对这一挑战,研究结合传统电力系统调频行为在多个时间尺度上的特性,考虑风电... 详细信息

随着风光发电占比逐渐增加,若其未有效参与调频或调频方式不当,系统在频率偏差维持方面将面临较大挑战,频率稳定性成为制约风电渗透率提升的关键因素。为了应对这一挑战,研究结合传统电力系统调频行为在多个时间尺度上的特性,考虑风电功率波动的时间尺度特征,采用不同的方法来挖掘传统火电机组在各个时间尺度上的调频潜力,以提高其对风电功率波动的灵活响应。基于分频段原理提出风电机组一次调频控制策略,通过分频段设置调差系数以提升一次调频能力,通过频域分析系统不同波动频段下的最优调频参数。结果表明,提出的方法显著增强了系统的频率稳定性。

关键词：风电机组一次调频分频段频率稳定性

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Upcycling electroplating sludge into bioengineering-enabled highly stable dual-site Fe-Ni_(2)P@C electrocatalysts for efficient oxygen evolution

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Nano Research 2024年第8期17卷 6984-6992页

作者： Jiawen Liu Zunpeng zuo feng Gao Kai Yi Jiahui Lin Mengye Wang Zhang Lin feng Huang State Key Laboratory of Optoelectronic Materials and Technologies School of MaterialsSun Yat-Sen UniversityGuangzhou 510275China Department of Chemistry City University of Hong KongHong Kong 999077China School of Metallurgy and Environment Central South UniversityChangsha 410083China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China

The advancement of bimetallic catalysts holds significant promise for the innovation of oxygen evolution reaction(OER)*** from adsorbate evolution mechanism(AEM)and lattice oxygen oxidation mechanism(LOM),the incorporation of dual active sites has the potential to foster novel OER pathways,such as the coupled oxygen evolution mechanism(COM),which can surpass the limitations of OER and elevate catalytic *** this study,uniformly distributed Fe/Ni dual-site Fe-Ni_(2)P@C electrocatalysts are crafted by upcycling metals in electroplating sludge via an eco-friendly and sustainable microbial engineering *** findings indicate that a substantial number of defects emerge at the Ni2P crystal during the OER process,laying the groundwork for lattice oxygen ***,the displacement of Ni/Fe in the crystal lattice intensifies the asymmetry of the electronic structure at the metal active sites,facilitating the deprotonation *** research introduces an innovative paradigm for the synthesis of effective and robust transition metal-based OER catalysts,with implications for sustainable energy generation technologies.

关键词： oxygen evolution reaction dual active sites adsorbate evolution mechanism lattice oxygen mechanism bioengineering

基于模糊数学评定与响应面法优化杏子与玫瑰花酱复合果丹皮的研制

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中国调味品 2024年第7期49卷 127-136页

作者：古丽米热·努尔麦麦提冯作山白羽嘉王晨张亚征朱志鹏新疆农业大学食品科学与药学学院乌鲁木齐830052 新疆果品采后科学与技术重点实验室乌鲁木齐830052

该研究在果丹皮传统配方工艺的基础上对复合果丹皮的辅料添加量配方进行了优化,以杏子和玫瑰花酱为主要原料,以酸味剂、凝胶剂、防腐剂为辅料,研制一款低糖复合果丹皮。采用单因素试验和Box-Behnken响应面优化法得到杏子与玫瑰花酱复合... 详细信息

该研究在果丹皮传统配方工艺的基础上对复合果丹皮的辅料添加量配方进行了优化,以杏子和玫瑰花酱为主要原料,以酸味剂、凝胶剂、防腐剂为辅料,研制一款低糖复合果丹皮。采用单因素试验和Box-Behnken响应面优化法得到杏子与玫瑰花酱复合果丹皮的感官评分和杏子与玫瑰花酱的质量比、柠檬酸添加量、复合胶添加量、苯甲酸钠添加量的模型,经验证,模型合理可靠。通过模型系数显著性检验,得到以感官评分为响应值的主效应关系均为柠檬酸添加量>复合胶添加量>杏子与玫瑰花酱的质量比>苯甲酸钠添加量。得出最佳配方为杏子与玫瑰花酱的质量比2∶1、柠檬酸添加量0.2%、复合胶添加量3%、苯甲酸钠添加量0.04%,此配方下得到的感官评分为90.33分,与模型预测值较一致。结果表明,此数学模型较好地预测了杏子与玫瑰花酱复合果丹皮的配方。

关键词：杏子与玫瑰花酱复合果丹皮配方工艺优化响应面试验感官评分数学模型

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2022年凉山州鸡肉、鸡蛋中兽药残留现状及膳食暴露评估

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实验室检测

实验室检测 2024年第1期2卷 35-41页

作者：左凤边腊红李芮李改弟米高权邝凡凉山州农业农村局农产品质量安全检测中心凉山615000 西昌市农业农村局植保植检站西昌615000

目的了解凉山州各鸡肉生产基地中鸡肉、鸡蛋兽药残留水平,评估其膳食暴露风险。方法采用液相色谱-质谱法对2022年凉山州17县市的353份鸡肉和鸡蛋中的喹诺酮类和喹噁啉类抗生素进行检测,采用点评估法进行兽药残留膳食风险评估。结果2022... 详细信息

目的了解凉山州各鸡肉生产基地中鸡肉、鸡蛋兽药残留水平,评估其膳食暴露风险。方法采用液相色谱-质谱法对2022年凉山州17县市的353份鸡肉和鸡蛋中的喹诺酮类和喹噁啉类抗生素进行检测,采用点评估法进行兽药残留膳食风险评估。结果2022年抽检的鸡肉共计221份,所检8种兽药中,兽药检出率为25.79%,不合格率为1.81%;其中鸡蛋132份,仅恩诺沙星检测出兽药残留,检出率为1.52%,不合格率为1.52%;通过点评估法对兽药残留膳食风险评估,其危害商远低于1,表明兽药残留对人体健康风险较低。结论2022年凉山州鸡肉和鸡蛋产养殖基地部分存在兽药残留超标现象,整体兽药残留对人体的健康危害较低,但部分不得检出的兽药对人体的健康风险仍不可忽视。

关键词：鸡肉鸡蛋兽药残留膳食暴露风险评估

Feasibility of Transabdominal Real-time CDFI and HDFI Techniques for Fetal Pulmonary Vein Display in the First Trimester

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Current Medical Science 2022年第3期42卷 635-641页

作者： Dong-mei LIN Yun-xiao ZHU Ying TAN Yu-jun HUANG Kun YUAN Wen-fen LIU zuo-feng XU Department of Medical Ultrasonics the Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen 518107China Department of Medical Ultrasonics South China Hospital of Shenzhen UniversityShenzhen 518000China

Objective This study aimed to assess the feasibility and usefulness of transabdominal color Doppler flow imaging(CDFI)technology and the high-definition flow imaging(HDFI)technique in detecting fetal pulmonary veins(PVs)in the first trimester(11–13^(+6)weeks).Methods From December 2018 to October 2019,328 pregnant women with 328 normal singleton fetuses(crown-rump length:45–84 mm)who had undergone CDFI and HDFI scans for fetal heart and vessel examination were enrolled in this *** cases were divided into three groups according to the gestational age:group A,11^(+0)−11^(+6)weeks;group B,12^(+0)−12^(+6)weeks;and group C,13^(+0)−13^(+6)*** sonograms and CDFI and HDFI images were analyzed by two senior radiologists independently and *** abilities of CDFI and HDFI to display PVs were *** Successful PV display rates via CDFI and HDFI were 2.3%and 68.2%(P<0.01),22.4%and 82.4%(P<0.01),41.5%and 91.2%(P<0.01)for group A,group B,and group C,*** total successful display rates for the two methods were 28.9%(CDFI)and 84.8%(HDFI)(P<0.01).Conclusions The HDFI technique is more valuable than CDFI for detecting PVs in early pregnancy(11–13^(+6)weeks).HDFI can detect at least one PV in all cases and may be used to detect pulmonary venous anomalies early.

关键词： pulmonary vein first trimester prenatal sonography high-definition flow imaging color Doppler flow imaging

Experimental and theoretical insight into carbamazepine degradation by chlorine-based advanced oxidation processes:Efficiency,energy consumption,mechanism and DBPs formation

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Journal of Environmental Sciences 2024年第5期139卷 72-83页

作者： Chunwei Liu zuo Tong How Yue Ju Li feng Xuefeng Ren Mohamed Gamal El-Din Key Laboratory ofCoal Processing and Efficient Utilization of Ministry of Education School of Chemical Engineering and TechnologyChina University of Mining and TechnologyJiangsu 221116China Department of Civil and Environmental Engineering University of AlbertaEdmonton T6G 1H9AlbertaCanada School of Environment and Spatial Informatics China University of Mining and TechnologyJiangsu 221116China Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation ofHainan Province School of Ecology and EnvironmentHainan UniversityHainan 570228China

Chlorine has been widely used in different advanced oxidation processes(AOPs)for micropollutants *** this study,different chlorine-based AOPs,namely medium pressure(MP)UV/chlorine,low pressure(LP)UV/chlorine,and in-situ chlorination,were compared for carbamazepine(CBZ)removal efficiency,energy consumption,and disinfection by-products(DBPs)*** three processes could achieve nearly 100%CBZ removal,while the reaction time needed by in-situ chlorination was double the time required by UV/chlorine *** energy consumed per magnitude of CBZ removed(EE/O)of MP UV/chlorine was 13 times higher than that of LP UV/chlorine,and relative to that of in-situ chlorination ***,MP and LP UV/chlorine processes generated one to two orders of magnitude more hydroxyl radicals(^(·)OH)and reactive chlorine species(RCS)than in-situ ***,RCS were the dominant reactive species,contributing to 78.3%,75.6%,and 71.6% of CBZ removal in MP,LP UV/chlorine,and in-situ chlorination,*** to the Gibbs free energy barriers between CBZ and RCS/^(·)OH calculated based on density functional theory(DFT),RCS had more reaction routes with CBZ and showed lower energy barrier in the main CBZ degradation pathways like epoxidation and formation of *** applied to secondary wastewater effluent,UV/chlorine and in-situ chlorination produced overall DBPs ranging from 104.77 to 135.41μg/***,the production of chlorate during UV/chlorine processes was 15 times higher than that during in-situ chlorination.

关键词： UV/chlorine In-situ chlorination Energy efficiency Role of reactive species DFT calculation Disinfection by-products