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基于非线性优化的激光无人叉车导航用外部参数的自动校准系统 被引量:1
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作者 邓智恒 刘洋 +2 位作者 段春雨 荆雄 李昌臣 《制造业自动化》 2024年第1期205-209,共5页
随着移动机器人SLAM导航技术的发展,采用基于工厂的实际环境进行导航的激光无人叉车已逐渐得到大量的应用,而激光无人叉车导航所使用的相关参数的精确性对激光无人叉车导航的精度和稳定性有很大的影响。因此,针对工业场景应用中的基于... 随着移动机器人SLAM导航技术的发展,采用基于工厂的实际环境进行导航的激光无人叉车已逐渐得到大量的应用,而激光无人叉车导航所使用的相关参数的精确性对激光无人叉车导航的精度和稳定性有很大的影响。因此,针对工业场景应用中的基于实际周围环境导航的激光无人叉车,对其相关导航用外部参数进行自动校准的问题开展研究非常必要。针对激光无人叉车的导航用外部参数进行自动校准的问题,采用高斯牛顿迭代法求解根据激光无人叉车运动学模型所计算得出的里程计位姿变化量和根据激光扫描帧匹配所计算得出的激光里程计位姿变化量之间偏差的最小化非线性函数,从而得出校准后精确的导航用外部参数数值,有效提高了激光无人叉车建图和定位的准确性。 展开更多
关键词 激光无人叉车 导航用外部参数 自动校准 帧间匹配 非线性优化
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Ca and Sr co-doping induced oxygen vacancies in 3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts for boosting low-temperature oxidative coupling of methane
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作者 Tongtong Wu Yuechang Wei +5 位作者 jing xiong Yitao Yang Zhenpeng Wang Dawei Han Zhen Zhao Jian Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期331-344,共14页
It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(... It is urgent to develop catalysts with application potential for oxidative coupling of methane(OCM)at relatively lower temperature.Herein,three-dimensional ordered macro porous(3 DOM)La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)(A_(2)B_(2)O_(7)-type)catalysts with disordered defective cubic fluorite phased structure were successfully prepared by a colloidal crystal template method.3DOM structure promotes the accessibility of the gaseous reactants(O2and CH4)to the active sites.The co-doping of Ca and Sr ions in La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts improved the formation of oxygen vacancies,thereby leading to increased density of surface-active oxygen species(O_(2)^(-))for the activation of CH4and the formation of C2products(C2H6and C2H4).3DOM La_(2-x)Sr_(x)Ce_(2-y)CayO_(7-δ)catalysts exhibit high catalytic activity for OCM at low temperature.3DOM La1.7Sr0.3Ce1.7Ca0.3O7-δcatalyst with the highest density of O_(2)^(-)species exhibited the highest catalytic activity for low-temperature OCM,i.e.,its CH4conversion,selectivity and yield of C2products at 650℃are 32.2%,66.1%and 21.3%,respectively.The mechanism was proposed that the increase in surface oxygen vacancies induced by the co-doping of Ca and Sr ions boosts the key step of C-H bond breaking and C-C bond coupling in catalyzing low-temperature OCM.It is meaningful for the development of the low-temperature and high-efficient catalysts for OCM reaction in practical application. 展开更多
关键词 3DOM catalysts Ca ions Sr ions Low-temperature oxidative couplingof methane Oxygen vacancies O_(2)^(-) species
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An Oracle Bone Inscription Detector Based on Multi-Scale Gaussian Kernels
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作者 Guoying Liu Shuanghao Chen +1 位作者 jing xiong Qingju Jiao 《Applied Mathematics》 2021年第3期224-239,共16页
The detection of Oracle Bone Inscriptions (OBIs) is one of the most fundamental tasks in the study of Oracle Bone, which aims to locate the positions of OBIs on rubbing images. The existing methods are based on the sc... The detection of Oracle Bone Inscriptions (OBIs) is one of the most fundamental tasks in the study of Oracle Bone, which aims to locate the positions of OBIs on rubbing images. The existing methods are based on the scheme of anchor boxes, involving complex network design and a great number of anchor boxes. In order to overcome the problem, this paper proposes a simpler but more effective OBIs detector by using an anchor-free scheme, where shape-adaptive Gaussian kernels are employed to represent the spatial regions of different OBIs. More specifically, to address the problem of misdetection caused by regional overlapping between some tightly distributed OBIs, the character regions are simultaneously represented by multiscale Gaussian kernels to obtain regions with sharp edges. Besides, based on the kernel predictions of different scales, a novel post-processing pipeline is used to obtain accurate predictions of bounding boxes. Experiments show that our OBIs detector has achieved significant results on the OBIs dataset, which greatly outperforms several mainstream object detectors in both speed and efficiency. Dataset is available at http://jgw.aynu.edu.cn. 展开更多
关键词 Oracle Bone Inscriptions Deep Learning Object Detection Hourglass Network
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Typos Correction in Overseas Chinese Learning Based on Chinese Character Semantic Knowledge Graph
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作者 jing xiong Xue Zhai +1 位作者 Zhan Zhang Feng Gao 《Journal of Data Analysis and Information Processing》 2023年第2期200-216,共17页
In recent years, more and more foreigners begin to learn Chinese characters, but they often make typos when using Chinese. The fundamental reason is that they mainly learn Chinese characters from the glyph and pronunc... In recent years, more and more foreigners begin to learn Chinese characters, but they often make typos when using Chinese. The fundamental reason is that they mainly learn Chinese characters from the glyph and pronunciation, but do not master the semantics of Chinese characters. If they can understand the meaning of Chinese characters and form knowledge groups of the characters with relevant meanings, it can effectively improve learning efficiency. We achieve this goal by building a Chinese character semantic knowledge graph (CCSKG). In the process of building the knowledge graph, the semantic computing capacity of HowNet was utilized, and 104,187 associated edges were finally established for 6752 Chinese characters. Thanks to the development of deep learning, OpenHowNet releases the core data of HowNet and provides useful APIs for calculating the similarity between two words based on sememes. Therefore our method combines the advantages of data-driven and knowledge-driven. The proposed method treats Chinese sentences as subgraphs of the CCSKG and uses graph algorithms to correct Chinese typos and achieve good results. The experimental results show that compared with keras-bert and pycorrector + ernie, our method reduces the false acceptance rate by 38.28% and improves the recall rate by 40.91% in the field of learning Chinese as a foreign language. The CCSKG can help to promote Chinese overseas communication and international education. 展开更多
关键词 Chinese Character Meaning Knowledge Graph Typos Correction OpenHowNet Semantic Relevancy
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水淹胁迫下的水竹根系生理响应与适应特征 被引量:5
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作者 金艺 李旭 +5 位作者 傅松玲 苏文会 范少辉 景雄 储昊煜 倪惠菁 《安徽农业大学学报》 CAS CSCD 2021年第1期1-8,共8页
水竹(Phyllostachys heteroclada Oliv.)是优良的笋材两用竹种,对其研究多围绕其丰产培育技术开展,关于水竹对水淹胁迫的适应特征与响应机制尚不清楚。为探究水淹胁迫下水竹的根系泌H+特征等生理响应及适应特征,通过人工模拟胁迫梯度,... 水竹(Phyllostachys heteroclada Oliv.)是优良的笋材两用竹种,对其研究多围绕其丰产培育技术开展,关于水竹对水淹胁迫的适应特征与响应机制尚不清楚。为探究水淹胁迫下水竹的根系泌H+特征等生理响应及适应特征,通过人工模拟胁迫梯度,采用非损伤微测技术(NMT),测定水竹根系在全淹及半淹条件下的H+流速、抗氧化酶活性、内源激素含量以及非结构性碳水化物含量等变化规律。结果表明:水竹遭受水淹胁迫后根系所处环境的酸碱水平发生改变,根系泌H+现象明显,随胁迫时间延长,通过自身调节适应胁迫逐渐使得H+外排现象回落。水竹根系超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性整体随胁迫程度增强而上升。另外,根系的淀粉和可溶性糖含量随水淹胁迫时间延长逐渐下降,水淹胁迫短时间内影响了水竹体内非结构性碳水化合物的含量,但含量仍在正常范围之内。综上,水竹遭受水淹胁迫后根系所处环境的酸碱水平发生改变,短时间内影响了水竹体内碳水化合物的含量,显著提高了根系抗氧化能力以清除活性氧(ROS);通过内源激素的协同作用,抑制自身生长以适应淹水环境。 展开更多
关键词 水竹 水淹胁迫 根部H+流速 抗氧化能力 内源激素 非结构性碳水化合物
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遮荫和干旱复合处理对黄藤幼苗个体生长及生理特性的影响 被引量:4
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作者 李雁冰 范少辉 +4 位作者 刘广路 陈本学 徐瑞晶 景雄 曾宪礼 《西北植物学报》 CAS CSCD 北大核心 2019年第6期1096-1104,共9页
以1年生黄藤(Daemonorops jenkinsiana)实生苗为试验材料,采用盆栽控制试验测定分析遮荫和干旱复合处理下黄藤幼苗的生长状况、叶片光合参数、生物量及生理特征的变化情况,以阐明遮荫和干旱复合处理对其生长和生理的影响规律。结果显示:... 以1年生黄藤(Daemonorops jenkinsiana)实生苗为试验材料,采用盆栽控制试验测定分析遮荫和干旱复合处理下黄藤幼苗的生长状况、叶片光合参数、生物量及生理特征的变化情况,以阐明遮荫和干旱复合处理对其生长和生理的影响规律。结果显示:(1)黄藤的株高、地径和功能叶片数目均随遮荫度上升而增加;植株叶片的生物量、净光合速率(Pn)、气孔导度(G s)、蒸腾速率(Tr)均随遮荫度上升而呈先上升后下降的趋势。(2)黄藤叶片的可溶性蛋白(SP)、脯氨酸(Pro)随着遮荫度的增加而先增加后下降,丙二醛(MDA)含量以及超氧化物歧化酶(SOD)、过氧化物酶(POD)活性则均呈先下降后上升的趋势。(3)中度遮荫时,黄藤的株高、地径、功能叶数目、叶片生物量的积累以及Pn、Tr、WUE、Pro和SP含量均显著升高(P<0.05),SOD活性和MDA含量则显著降低(P<0.05)。(4)干旱胁迫导致黄藤的株高、地径、功能叶片数目、叶片生物量积累、Pn、Tr、WUE显著降低,SOD活性、POD活性、MDA含量和Pro含量均显著升高。研究发现,遮荫和干旱复合作用影响黄藤幼苗的生长和发育。黄藤幼苗能通过调整生长策略、光合策略、代谢策略等使植株逐步适应或耐受胁迫,表现出一定的抗旱性和喜阴性;中度遮荫(遮光20%~30%)能够改善黄藤幼苗的生境,并能缓解干旱胁迫对植株造成的伤害,对其生长有利。 展开更多
关键词 黄藤 干旱胁迫 遮荫 生长 生理特性
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良性前列腺增生经尿道前列腺等离子电切术临床路径释义 被引量:1
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作者 阎思宇 黄兴 +21 位作者 陈征 杨璐 贾招辉 彭谋 任选义 熊晶 李晓东 徐晓峰 孙中义 王永博 李绪辉 胡万里 王婷 靳英辉 訾豪 刘同族 曾宪涛 贺大林 王行环 中国研究型医院学会泌尿外科学专业委员会 中国医疗保健国际交流促进会循证医学分会 国家重点研发计划微创等离子手术体系研发和产业化项目组 《医学新知》 CAS 2022年第3期214-222,共9页
良性前列腺增生是引发中老年男性排尿功能障碍最为常见的一种良性疾病,也是导致下尿路症状的主要原因。经尿道前列腺等离子电切术效果好、安全可靠,已在临床中广泛应用。为进一步规范该手术的临床应用,国家卫生健康委员会于2019年首次... 良性前列腺增生是引发中老年男性排尿功能障碍最为常见的一种良性疾病,也是导致下尿路症状的主要原因。经尿道前列腺等离子电切术效果好、安全可靠,已在临床中广泛应用。为进一步规范该手术的临床应用,国家卫生健康委员会于2019年首次发布了《良性前列腺增生经尿道前列腺等离子电切术临床路径》。鉴于临床路径的篇幅有限,本文以该路径为蓝本,遵照循证医学的思路与方法进行释义,旨在提供更为详尽的证据补充,以帮助医护人员和管理人员能更好地理解、把握和正确运用本临床路径。 展开更多
关键词 临床路径 良性前列腺增生 下尿路症状 经尿道等离子电切术 等离子双极电切术 循证医学
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膀胱肿瘤经尿道等离子电切术临床路径释义 被引量:1
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作者 阎思宇 黄兴 +20 位作者 陈征 杨璐 贾招辉 彭谋 任选义 熊晶 李晓东 徐晓峰 王永博 李绪辉 郑航 王婷 靳英辉 訾豪 刘同族 曾宪涛 贺大林 王行环 中国研究型医院学会泌尿外科学专业委员会 中国医疗保健国际交流促进会循证医学分会 国家重点研发计划微创等离子手术体系研发和产业化项目组 《医学新知》 CAS 2022年第2期81-89,共9页
膀胱癌是全球第十大最常被诊断出的癌症,在男性中更常见。经尿道膀胱肿瘤电切术既是膀胱肿瘤的重要诊断方法,也是非肌层浸润性膀胱癌的主要治疗手段。相较于传统单极电切,等离子双极电切具有手术效果好、并发症较少的优势,临床应用渐趋... 膀胱癌是全球第十大最常被诊断出的癌症,在男性中更常见。经尿道膀胱肿瘤电切术既是膀胱肿瘤的重要诊断方法,也是非肌层浸润性膀胱癌的主要治疗手段。相较于传统单极电切,等离子双极电切具有手术效果好、并发症较少的优势,临床应用渐趋广泛。为规范常见病的诊疗,国家卫健委持续发布相关的临床路径,但临床路径的内容有限,对其进行释义可以更好的推广使用。本释义以最新发布的《膀胱肿瘤经尿道等离子电切术临床路径(2019年版)》为蓝本,采用循证医学的方法,对路径中涉及的给药方案进行了详细解读,以期为医护及管理人员能够更好地理解、把握和正确运用临床路径提供参考。 展开更多
关键词 临床路径 膀胱肿瘤 非肌层浸润性膀胱癌 经尿道等离子电切术 等离子双极电切术 循证医学
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基于GC-IMS和电子鼻技术分析贮酒容器对凤香型白酒香气成分的影响 被引量:35
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作者 刘丽丽 杨辉 +4 位作者 荆雄 徐晨 张亚芳 阎宗科 祁耀华 《食品科学》 EI CAS CSCD 北大核心 2022年第4期257-263,共7页
为研究贮酒容器对凤香型白酒香气成分的影响,采用电子鼻与气相色谱离子迁移谱(gas chromatographyion mobility spectrometry,GC-IMS)技术对不同容器贮存的凤香型白酒风味物质及理化指标——乙醇体积分数、总酸、总酯、可溶性固形物质... 为研究贮酒容器对凤香型白酒香气成分的影响,采用电子鼻与气相色谱离子迁移谱(gas chromatographyion mobility spectrometry,GC-IMS)技术对不同容器贮存的凤香型白酒风味物质及理化指标——乙醇体积分数、总酸、总酯、可溶性固形物质量浓度及pH值进行分析和比较,以期为凤香型白酒贮存工艺的改进提供参考。电子鼻和GC-IMS分析结果均表明:新产酒与贮酒香气特征有显著差别,陶坛与不锈钢罐贮酒风格相似,而酒海贮酒风格独特。GC-IMS在4类酒样中共检测出66种挥发性成分,主要为酯类、醛类、酮类、醇类物质;不锈钢罐和陶坛贮酒中乙醇酯类、双乙酰、1-丙醇等物质相对含量较高,在酒海贮酒中含有较多的高级醇酯类、醛酮类等物质;酒海贮酒中具有最低总酸质量浓度,最高可溶性固形物质量浓度、乙醇体积分数和最高的pH值。 展开更多
关键词 电子鼻 气相色谱离子迁移谱 酒海 陶坛 白酒
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非酿酒酵母与酿酒酵母混合发酵柿子酒特性的研究 被引量:17
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作者 荆雄 杨辉 +2 位作者 苏文 董腾达 黄莎莎 《中国酿造》 CAS 北大核心 2018年第12期52-56,共5页
基于非酿酒酵母代谢产物可提升酒的香气和风味物质,将两种非酿酒酵母柠檬形克勒克酵母(Klockera apiculata)和东方伊萨酵母(Issatchenkia orientalis)用于柿子酒发酵,研究两种非酿酒酵母对酒精、二氧化硫、单宁的耐受性和产β-葡萄糖苷... 基于非酿酒酵母代谢产物可提升酒的香气和风味物质,将两种非酿酒酵母柠檬形克勒克酵母(Klockera apiculata)和东方伊萨酵母(Issatchenkia orientalis)用于柿子酒发酵,研究两种非酿酒酵母对酒精、二氧化硫、单宁的耐受性和产β-葡萄糖苷酶的能力;对它们分别与酿酒酵母(Saccharomyces cerevisiae)混合发酵柿子酒的特性进行研究。结果表明,东方伊萨酵母在各方面耐受性均优于柠檬形克勒克酵母,但产β-葡萄糖苷酶的能力却较弱;两种非酿酒酵母单菌发酵性能都较弱,东方伊萨酵母单菌发酵结束酒精度为4.51%vol,而柠檬形克勒克酵母单菌发酵酒精度只有3.05%vol;两种非酿酒酵母与酿酒酵母混菌发酵7 d后,酒精度均达到10%vol以上。 展开更多
关键词 柠檬形克勒克酵母 东方伊萨酵母 酿酒酵母 发酵 柿子酒 特性
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不同贮酒容器对凤香型白酒风味物质的影响 被引量:13
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作者 刘丽丽 杨辉 +4 位作者 荆雄 张亚芳 阎宗科 祁耀华 徐晨 《食品科学》 EI CAS CSCD 北大核心 2022年第16期285-293,共9页
为探索贮酒容器对凤香型白酒风味物质的影响,采用气相色谱法、顶空固相微萃取及气相色谱-质谱联用法和超高效液相色谱法,以新酒为对照,对酒海贮酒、陶坛贮酒、不锈钢罐贮酒及对照4种酒样的风味物质进行分析。结果鉴定出酯类、醇类、酸... 为探索贮酒容器对凤香型白酒风味物质的影响,采用气相色谱法、顶空固相微萃取及气相色谱-质谱联用法和超高效液相色谱法,以新酒为对照,对酒海贮酒、陶坛贮酒、不锈钢罐贮酒及对照4种酒样的风味物质进行分析。结果鉴定出酯类、醇类、酸类、醛酮类和酚类5类组分;其中,新酒的风味物质种类最少,其总质量浓度最高(79种、7 756 mg/L),酒海贮酒的风味物质种类较多,但其质量浓度最低(94种、4 276 mg/L),而陶坛和不锈钢罐贮酒种类最多,均为96种;其总质量浓度低于新酒而高于酒海贮酒(分别为5 957 mg/L和5 360 mg/L)。主成分分析及热图分析结果表明,不锈钢罐和陶坛贮酒在异戊醇、异丁醇、月桂酸乙酯、己酸-2-苯乙酯、己酸糠酯和乙缩醛等物质上具有较高的相关性,呈花香和果香的特征;酒海贮酒在十八酸乙酯、亚麻酸乙酯、苯乙醇和苯甲醛等物质上具有较高相关性,呈果香、甜香、蜜香和杏仁香特征。贮酒容器对贮酒中风味物质的影响可能与贮酒容器的透气性、释放过渡金属离子的性能以及对贮酒pH值的影响有关。 展开更多
关键词 贮酒容器 凤香型白酒 风味物质 气相色谱法 顶空固相微萃取-气相色谱-质谱联用法 超高效液相色谱法
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Three-dimensional ordered macroporous perovskite-type La_(1-x)K_xNiO_3 catalysts with enhanced catalytic activity for soot combustion: the Effect of K-substitution 被引量:8
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作者 Xuelei Mei jing xiong +4 位作者 Yuechang Wei Chujun Wang Qiangqiang Wu Zhen Zhao Jian Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期722-732,共11页
Three-dimensional ordered macroporous (3DOM) La1?xKxNiO3 perovskite-type catalysts were successfully prepared by a colloidal crystal template method and characterized by scanning electron microscopy, transmission elec... Three-dimensional ordered macroporous (3DOM) La1?xKxNiO3 perovskite-type catalysts were successfully prepared by a colloidal crystal template method and characterized by scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray scattering elemental mapping, X-ray diffraction, Raman and X-ray photoelectron spectroscopy, and temperature-programmed reduction of H2. Further, their catalytic activity in soot combustion was determined by temperature-programmed oxidation reaction. K substitution into the LaNiO3 lattice led to remarkably improved catalytic activity of this catalyst in soot combustion. Amongst various catalysts, La0.95K0.05NiO3 exhibited the highest activity in soot combustion (with its T50 and CO2 S values being 338 °C and 98.2%, respectively), which is comparable to the catalytic activities of Pt-based catalysts under the condition of poor contact between the soot and the catalyst. K-substitution improves the valence state of Ni and increases the number of oxygen vacancies, thereby leading to increased density of surface-active oxygen species. The active oxygen species play a vital role in catalyzing the elimination of soot. The perovskite-type La1?xKxNiO3 nanocatalysts with 3DOM structure without noble metals have potential for practical applications in the catalytic combustion of diesel soot particles. 展开更多
关键词 Three-dimensional ordered macroporous material LANIO3 Potassium Perovskite Soot combustion
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Positioning performance analysis on combined GPS/BDS precise point positioning 被引量:7
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作者 jing xiong Fei Han 《Geodesy and Geodynamics》 2020年第1期78-83,共6页
Combining the observation data from five Multi-GNSS Experiment(MGEX)stations with the precise orbit and clock products from Global Positioning System(GPS)and BeiDou Navigation Satellite System(BDS),we studied the mode... Combining the observation data from five Multi-GNSS Experiment(MGEX)stations with the precise orbit and clock products from Global Positioning System(GPS)and BeiDou Navigation Satellite System(BDS),we studied the model of combined GPS/BDS precise point positioning,and then analyzed the convergence speed and short-time(6 h)positioning accuracy.The calculation results show that in static positioning,the average convergence time of GPS is about 50 min,and its horizontal accuracy is better than 2 cm while the vertical accuracy is better than 4 cm.The convergence speed of combined GPS/BDS is about 40 min,and its positioning accuracy is close to that of GPS.In kinematic positioning,the average convergence time of GPS is about 72 min,and its horizontal accuracy is better than 5 cm while the vertical accuracy is better than 12 cm.The average convergence time of GPS/BDS is about 57 min,and its horizontal accuracy is better than 3 cm while the vertical accuracy is better than 9 cm.Combined GPS/BDS has significantly improved the convergence speed,and its positioning accuracy is slightly than that of GPS. 展开更多
关键词 COMBINED GPS/BDS PRECISE point POSITIONING CONVERGENCE SPEED POSITIONING accuracy
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基于衍生化GC-MS代谢组学方法分析凤香型年份基酒的差异 被引量:6
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作者 杨辉 刘丽丽 +4 位作者 荆雄 张亚芳 徐晨 阎宗科 祁耀华 《现代食品科技》 CAS 北大核心 2021年第11期295-303,共9页
借助衍生化方法和气相色谱-质谱联用仪检测,并结合代谢组学的分析方法,对不同年份基酒中差异化合物进行研究。结果表明:不同年份基酒共鉴定出59种化合物,包括30种有机酸、10种氨基酸、7种糖类物质、7种糖醇类物质和5种其他化合物。样本... 借助衍生化方法和气相色谱-质谱联用仪检测,并结合代谢组学的分析方法,对不同年份基酒中差异化合物进行研究。结果表明:不同年份基酒共鉴定出59种化合物,包括30种有机酸、10种氨基酸、7种糖类物质、7种糖醇类物质和5种其他化合物。样本树状图、PCA和PLS-DA分析发现新酒和贮存2年的酒归为一类,贮存3年和5年的酒归为一类,贮存7年和9年的酒归为一类,不同年份基酒之间分类明显,表明不同年份基酒之间在化合物种类和含量上存在明显差别。通过VIP变量重要性筛选出20种差异化合物,包括有机酸、氨基酸、糖类、甘油等,这些物质在贮存过程中含量明显升高,这与酒海制作过程中内壁材料的特殊性有关,这也是新酒经过酒海贮存一段时间后酒体变得更加醇厚的原因,酒海贮存对于酒体风味的形成具有重要作用。 展开更多
关键词 衍生化 气相色谱-质谱联用(GC-MS) 代谢组学 年份酒 差异化合物
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基于GC-MS和GC-IMS技术分析凤香型年份基酒挥发性成分 被引量:8
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作者 刘丽丽 杨辉 +4 位作者 荆雄 张亚芳 徐晨 阎宗科 祁耀华 《食品工业科技》 CAS 北大核心 2022年第23期318-327,共10页
以酒海贮存的凤香型年份基酒为研究对象,采用气相色谱-质谱联用(Gas Chromatography-Mass Spectrometry,GC-MS)和气相离子迁移谱(Gas Chromatography-Ion Mobility Spectroscopy,GC-IMS)技术分析凤香型基酒在酒海贮存过程中挥发性物质... 以酒海贮存的凤香型年份基酒为研究对象,采用气相色谱-质谱联用(Gas Chromatography-Mass Spectrometry,GC-MS)和气相离子迁移谱(Gas Chromatography-Ion Mobility Spectroscopy,GC-IMS)技术分析凤香型基酒在酒海贮存过程中挥发性物质变化。结果表明:GC-MS检出85种化合物,其中酯类41种、酸类10种和醇类物质17种,且包含一些分子量较大的化合物,在贮存过程中,酯类物质下降明显,酸类物质含量上升,棕榈酸乙酯、亚油酸乙酯、反油酸乙酯、十八酸乙酯等高级脂肪酸酯、苯乙醇呈线性增长。GC-IMS定性出47种,以酯类(23种)、醛酮类(14种)为主,其对小分子物质较为灵敏,二丙基硫醚、异戊烷、双乙酰等物质含量随时间的增加呈上升趋势;两种技术的主成分分析(PCA)均说明年份基酒之间差异显著。在两种技术手段的协同下,获得了陈酿过程中凤香型基酒挥发性成分变化规律,主要表现为:酸升酯降,棕榈酸乙酯、亚油酸乙酯、反油酸乙酯、十八酸乙酯、苯乙醇、苯甲醛、二甲基硫醚、乳酸含量明显增加,为凤香型基酒陈酿体系的建立提供理论依据。 展开更多
关键词 气相色谱-质谱联用 气相离子迁移谱 酒海 白酒 挥发性物质
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Fabrication of ultrafine Pd nanoparticles on 3D ordered macroporous TiO_2 for enhanced catalytic activity during diesel soot combustion 被引量:4
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作者 Yuechang Wei Qiangqiang Wu +2 位作者 jing xiong Jian Liu Zhen Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期606-612,共7页
Nanocatalysts consisting of three‐dimensionally ordered macroporous(3DOM)TiO2‐supported ultrafine Pd nanoparticles(Pd/3DOM‐TiO2‐GBMR)were readily fabricated by gas bubbling‐assisted membrane reduction(GBMR)method... Nanocatalysts consisting of three‐dimensionally ordered macroporous(3DOM)TiO2‐supported ultrafine Pd nanoparticles(Pd/3DOM‐TiO2‐GBMR)were readily fabricated by gas bubbling‐assisted membrane reduction(GBMR)method.These catalysts had a well‐defined and highly ordered macroporous nanostructure with an average pore size of 280 nm.In addition,ultrafine hemispherical Pd nanoparticles(NPs)with a mean particle size of 1.1 nm were found to be well dispersed over the surface of the 3DOM‐TiO2 support and deposited on the inner walls of the material.The nanostructure of the 3DOM‐TiO2 support ensured efficient contact between soot particles and the catalyst.The large interface area between the ultrafine Pd NPs and the TiO2 also increased the density of sites for O2 activation as a result of the strong metal(Pd)‐support(TiO2)interaction(SMSI).A Pd/3DOM‐TiO2‐GBMR catalyst with ultrafine Pd NPs(1.1 nm)exhibited higher catalytic activity during diesel soot combustion compared with that obtained from a specimen having relatively large Pd NPs(5.0 nm).The T10,T50 and T90 values obtained from the former were 295,370 and 415°C.Both the activity and nanostructure of the Pd/3DOM‐TiO2‐GBMR catalyst were stable over five replicate soot oxidation trials.These results suggest that nanocatalysts having a 3DOM structure together with ultrafine Pd NPs can decrease the amount of Pd required,and that this approach has potential practical applications in the catalytic combustion of diesel soot particles. 展开更多
关键词 Ordered macroporous material Pd TiO2 Diesel soot combustion Ultrafine nanoparticle Heterogeneous catalysis
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响应面法优化乳酸菌冻干保护剂配方 被引量:13
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作者 杨辉 闫晓哲 +2 位作者 杜姣姣 荆雄 董腾达 《陕西科技大学学报》 CAS 2018年第2期31-38,共8页
以复合乳酸菌发酵果渣浸提液的副产物-乳酸菌泥为原料,以冻干粉的菌存活率(R1),单位质量菌粉活菌数(R2)为评价指标,通过单因素实验、Plackett-Burman试验、爬坡实验和响应面实验设计方案优化冻干保护剂配方.实验发现当保护剂为低聚木糖... 以复合乳酸菌发酵果渣浸提液的副产物-乳酸菌泥为原料,以冻干粉的菌存活率(R1),单位质量菌粉活菌数(R2)为评价指标,通过单因素实验、Plackett-Burman试验、爬坡实验和响应面实验设计方案优化冻干保护剂配方.实验发现当保护剂为低聚木糖、菊糖、NaHCO3且添加量分别为14.5%、6.28%、0.92%时,乳酸菌冻干粉菌存活率为(82.87±4.28)%,与空白组相比存活率提高了68.27%,结果表明试验所得保护剂制备乳酸菌冻干粉是可行的,为乳酸菌饲料等产品的制备提供技术支撑. 展开更多
关键词 乳酸菌菌泥 保护剂 活菌率
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Variable valence Mo^(5+)/Mo^(6+)ionic bridge in hollow spherical g-C_(3)N_(4)/Bi_(2)MoO_(6) catalysts for promoting selective visible light-driven CO_(2)photoreduction into CO 被引量:3
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作者 Wenjie He Yuechang Wei +8 位作者 jing xiong Zhiling Tang Yingli Wang xiong Wang Hui Xu Xiao Zhang Xiaolin Yu Zhen Zhao Jian Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期361-372,I0009,共13页
Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ioni... Herein,the catalysts of ultrathin g-C_(3)N_(4)surface-modified hollow spherical Bi2MoO6(g-C_(3)N_(4)/Bi2MoO6,abbreviated as CN/BMO)were fabricated by the co-solvothermal method.The variable valence Mo^(5+)/Mo^(6+)ionic bridge in CN/BMO catalysts can boost the rapid transfer of photogenerated electrons from Bi2MoO6to g-C_(3)N_(4).And the synergy effect of g-C_(3)N_(4)and Bi2MoO6components remarkably enhance CO_(2)adsorption capability.CN/BMO-2 catalyst has the best performances for visible light-driven CO_(2)reduction compared with single Bi2MoO6and g-C_(3)N_(4),i.e.,its amount and selectivity of CO product are 139.50μmol g-1and 96.88%for 9 h,respectively.Based on the results of characterizations and density functional theory calculation,the photocatalytic mechanism for CO_(2)reduction is proposed.The high-efficient separation efficiency of photogenerated electron-hole pairs,induced by variable valence Mo^(5+)/Mo^(6+)ionic bridge,can boost the rate-limiting steps(COOH*-to-CO*and CO*desorption)of selective visible light-driven CO_(2)conversion into CO.It inspires the establishment of efficient photocatalysts for CO_(2)conversion. 展开更多
关键词 g-C_(3)N_(4) Bi_(2)MoO_(6) Mo^(5+)/Mo^(6+)ionic bridge CO_(2)photoconversion CO production
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复合酶解及大曲糖化对柿子出汁率和还原糖度的影响 被引量:3
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作者 杨辉 荆雄 +2 位作者 苏文 董腾达 黄莎莎 《陕西科技大学学报》 CAS 2018年第4期52-56,62,共6页
柿子汁的获取是柿子酒、柿子醋生产的关键工序,其中出汁率和糖度低是产业化的瓶颈,为了提高柿子出汁率和糖度、延长生产周期,文中以陕西彬县的新鲜柿子为原料,采用催熟、复合酶酶解和大曲糖化等技术提取柿汁,研究了影响出汁率和糖度的因... 柿子汁的获取是柿子酒、柿子醋生产的关键工序,其中出汁率和糖度低是产业化的瓶颈,为了提高柿子出汁率和糖度、延长生产周期,文中以陕西彬县的新鲜柿子为原料,采用催熟、复合酶酶解和大曲糖化等技术提取柿汁,研究了影响出汁率和糖度的因素,通过正交试验对复合酶解和糖化条件进行了优化,分析了酶解前后营养成分的变化.结果表明,复合酶解和大曲糖化可以提高柿汁的出汁率和糖度,在果胶酶用量0.03%、纤维素酶用量0.015%、酶解温度50℃、对柿子果浆酶解2.5h,然后,在大曲用量2wt%、温度60℃条件下糖化2.5h,柿子出汁率可达64.43%、还原糖含量为120.27g/L、总酸含量为1.72g/L、总黄酮含量为0.113g/L、多酚含量为0.218g/L、维生素C含量为0.060g/L.与不经过酶解、糖化处理的柿子出汁率和还原糖含量相比分别提高了25.85%和51.87%,而其他营养成分则基本保持不变. 展开更多
关键词 柿子 出汁率 酶解 糖化 正交试验
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Stability and control of dynamic walking for a five-link planar biped robot with feet 被引量:2
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作者 Chenglong FU Ken CHEN +1 位作者 jing xiong Leon XU 《控制理论与应用(英文版)》 EI 2007年第2期113-120,共8页
During dynamic walking of biped robots, the underactuated rotating degree of freedom (DOF) emerges between the support foot and the ground, which makes the biped model hybrid and dimension-variant. This paper addres... During dynamic walking of biped robots, the underactuated rotating degree of freedom (DOF) emerges between the support foot and the ground, which makes the biped model hybrid and dimension-variant. This paper addresses the asymptotic orbit stability for dimension-variant hybrid systems (DVHS). Based on the generalized Poincare map, the stability criterion for DVHS is also presented, and the result is then used to study dynamic walking for a five-link planar biped robot with feet. Time-invariant gait planning and nonlinear control strategy for dynamic walking with fiat feet is also introduced. Simulation results indicate that an asymptotically stable limit cycle of dynamic walking is achieved by the proposed method. 展开更多
关键词 Biped robot Dynamic walking Orbit stability Dimension-variant hybrid systems Nonlinear control
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