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Pressure generation under deformation in a large-volume press

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CHINESE PHYSICS B 2024年第9期33卷 622-626页

作者： wang, saisai Zhao, Xinyu Hu, Kuo Feng, Bingtao Hou, Xuyuan Zhang, Yiming Liu, Shucheng Shang, Yuchen Liu, Zhaodong Yao, Mingguang Liu, Bingbing Jilin Univ Coll Phys State Key Lab Superhard Mat Synerget Extreme Condit User Facil Changchun 130012 Peoples R China Jilin Univ Coll Earth Sci Changchun 130012 Peoples R China

Deformation can change the transition pathway of materials under high pressure, thus significantly affects physical and chemical properties of matters. However, accurate pressure calibration under deformation is challenging and thereby causes relatively large pressure uncertainties in deformation experiments, resulting in the synthesis of complex multiphase materials. Here, pressure generations of three types of deformation assemblies were well calibrated in a Walker-type large-volume press (LVP) by electrical resistance measurements combined with finite element simulations (FESs). Hard Al2O3 or diamond pistons in shear and uniaxial deformation assemblies significantly increase the efficiency of pressure generation compared with the conventional quasi-hydrostatic assembly. The uniaxial deformation assembly using flat diamond pistons possesses the highest efficiency in these deformation assemblies. This finding is further confirmed by stress distribution analysis based on FESs. With this deformation assembly, we found shear can effectively promote the transformation of C60 into diamond under high pressure and realized the synthesis of phase-pure diamond at relatively moderate pressure and temperature conditions. The present developed techniques will help improve pressure efficiencies in LVP and explore the new physical and chemical properties of materials under deformation in both science and technology.

关键词： shear/uniaxial deformation pressure calibration finite element simulations large-volume press high pressure 81.40.Lm 07.35.+k 62.50.-p 81.40.Vw SIMPLE SHEAR DEFORMATION DISLOCATION MOBILITY SEISMIC ANISOTROPY TEMPERATURE OLIVINE DIA ACTIVATION CARBON PHASE

基于Canny-Harris角点检测的光学元件表面疵病检测

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机械与电子 2024年第8期42卷 26-33页

作者：王赛赛周阿维西安工程大学机电工程学院陕西西安710600

为提高光学元件表面疵病检测的准确性,提出了一种基于Canny-Harris角点检测的光学元件表面疵病检测方法。该方法首先利用基于迭代式阈值的Canny算子对图像进行边缘检测,得到候选角点;接着,利用基于局部窗口角点密度的可变窗口非极大值... 详细信息

为提高光学元件表面疵病检测的准确性,提出了一种基于Canny-Harris角点检测的光学元件表面疵病检测方法。该方法首先利用基于迭代式阈值的Canny算子对图像进行边缘检测,得到候选角点;接着,利用基于局部窗口角点密度的可变窗口非极大值抑制方法去除候选角点中的伪角点,以得到检测精度更高的Canny-Harris角点检测算法;然后,利用Canny-Harris角点检测算法进行图像拼接,并利用边界测定法提取出拼接图像中的疵病特征;最后,通过计算疵病的形状因子,实现对疵病的分类。实验结果表明,该方法能够成功实现子孔径图像的精确拼接,并准确地检测出光学元件表面疵病信息。

关键词：光学元件疵病检测 Canny-Harris算法图像拼接疵病识别

气候变化情景下北江流域骤发干旱特征变化预测

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水文 2024年第2期44卷 96-102页

作者：雷勇王赛赛陈蓓武传号珠江水利委员会珠江水利科学研究院广东广州510640 暨南大学环境学院广东广州511443 暨南大学生命科学技术学院广东广州510632 河海大学水灾害防御全国重点实验室江苏南京210098

以北江流域为研究对象,利用VIC(Variable Infiltration Capacity)模型与CMIP5全球气候模式耦合构建了流域水循环模型,基于模型输出的蒸发和潜在蒸发数据,构建基于SESR指数的骤发干旱(简称骤旱)识别方法,评估2021—2050年三种排放情景下(... 详细信息

以北江流域为研究对象,利用VIC(Variable Infiltration Capacity)模型与CMIP5全球气候模式耦合构建了流域水循环模型,基于模型输出的蒸发和潜在蒸发数据,构建基于SESR指数的骤发干旱(简称骤旱)识别方法,评估2021—2050年三种排放情景下(RCP2.6、RCP4.5、RCP8.5)骤旱特征(频次、历时、强度)相对于基准期(1971—2000)的变化及不确定性。结果表明,在RCP情景下:(1)流域呈持续增暖趋势,且排放情景越高升温幅度越大,降水、蒸发和潜在蒸发呈总体呈减小趋势,但潜在蒸发减小幅度小于蒸发;(2)骤旱频次在流域西部(东部)减少(增加),且增幅随排放情景上升而增大(<80%),流域东北部和南部预计会遭遇强度更高、历时更长的骤旱过程;(3)不同骤旱特征预测的不确定性差异较大,且均呈现出较强的空间异质性。

关键词：骤旱 VIC模型气候模式情景预测不确定性

Ru/AC和Ru-NPs/AC催化剂对乙炔氢氯化反应催化活性的比较

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高校化学工程学报 2024年第4期38卷 578-585页

作者：徐达王赛赛马腾云万立祺赵佳蔡海婷李小年浙江工业大学化学工程学院浙江杭州310014

针对乙炔氢氯化反应无汞催化剂的开发,Ru基催化剂是最具工业潜力的催化剂之一。结合表面积分析仪(BET)、程序升温还原(TPR)、透射电镜(TEM)和程序升温脱附(TPD),以及动力学实验探究了导致Ru/AC(AC为活性炭)和高温H_(2)处理后Ru-NPs/AC... 详细信息

针对乙炔氢氯化反应无汞催化剂的开发,Ru基催化剂是最具工业潜力的催化剂之一。结合表面积分析仪(BET)、程序升温还原(TPR)、透射电镜(TEM)和程序升温脱附(TPD),以及动力学实验探究了导致Ru/AC(AC为活性炭)和高温H_(2)处理后Ru-NPs/AC催化性能差异的原因。在排除内、外扩散的条件下,通过动力学实验判断了反应级数,初步推测了基元反应步骤和决速步骤。结果表明,Ru-NPs/AC相对于Ru/AC总反应速率更低,表观活化能更高,这是由于高温H_(2)处理后活性组分的分散度降低、Ru物种被还原,并且导致活性中心对C_(2)H_(2)的吸附性能降低。

关键词：乙炔氢氯化 Ru基催化剂反应级数表观活化能活性中心

短横轴截割机器人直墙拱形巷道自动成形控制方法

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西安科技大学学报 2024年第3期44卷 418-429页

作者：马宏伟王赛赛王川伟薛力猛张恒孙思雅西安科技大学机械工程学院陕西西安710054 陕西省矿山机电装备智能检测与控制重点实验室陕西西安710054 西安科技大学电气与控制工程学院陕西西安710054

针对掘进机在直墙拱形巷道掘进过程中存在定位难、截割效率低、成形质量差等问题,提出一种短横轴截割机器人及其自动成形控制方法。首先设计了串联式短横轴截割机器人结构,构建了短横轴截割机器人运动学模型,建立了截割臂升降油缸、滑... 详细信息

针对掘进机在直墙拱形巷道掘进过程中存在定位难、截割效率低、成形质量差等问题,提出一种短横轴截割机器人及其自动成形控制方法。首先设计了串联式短横轴截割机器人结构,构建了短横轴截割机器人运动学模型,建立了截割臂升降油缸、滑移油缸及回转油缸伸缩量与截割头末端位姿的数学关系,提出了短横轴截割机器人直墙拱形巷道自动成形控制方法;其次研究分析了短横轴截割机器人截割头包络空间与直墙半圆拱形巷道空间耦合关系,确定了截割过程中截割轨迹关键点位置,提出了基于截割轨迹关键点的“弓”型截割轨迹规划方法;然后根据建立的短横轴截割机器人运动学模型,求解截割头在跟踪截割轨迹的过程中运动控制量和截割、修帮、扫底3个任务各个关节控制时序;最后以模糊PID为例,建立了短横轴截割机器人自动成形控制方法,利用Adams软件对短横轴截割机器人进行截割运动仿真试验。结果表明:利用“弓”型截割轨迹规划方法能够完成直墙拱形巷道的截割轨迹规划,控制截割头对截割轨道进行跟踪控制,实现了直墙拱形巷道断面的自动成形截割,截割成形的巷道最大欠挖量为48 mm,最大超挖量为21 mm,满足煤矿巷道成形质量要求。研究得出短横轴截割机器人可在沿巷道中线不左右移机的情况下,高效率、高质量地完成直墙拱形巷道断面自动成形截割任务。

关键词：定形截割截割机器人拱形巷道轨迹规划模糊PID控制

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Application of endoscopic mucosal advancement in the treatment of chronic anastomotic leakage:A case report

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Laparoscopic, Endoscopic and Robotic Surgery 2022年第3期5卷 124-127页

作者： Qunmin wang Feixia wang saisai wang Hanju Hua Department of Colorectal Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Anastomotic leakage is one of the most serious postoperative complications after colorectal surgery.A fistula or chronic sinus formation is one kind of anastomotic *** fistulas may heal after conservative treatment,but some patients will develop a chronic anastomotic leakage,which definitely requires elective surgery due to the formation of a sinus tract or an internal *** study reports a case of an 88-year-old man with sigmoid colon cancer who developed a chronic anastomotic leakage after colorectal *** mucosal advancement combined with titanium clips was success-fully performed to close the *** patient was discharged 12 days after the operation and resumed a normal diet 1 week after *** mucosal advancement could be an alternative choice for the treatment of chronic anastomotic leakage and can prevent a secondary surgery;however,good bowel preparation and strict inclusion criteria are required.

关键词： Endoscopy Elderly colon cancer Anastomotic leakage Titanium clip

改进的ORB-FLANN煤矸石图像高效匹配方法

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煤炭科学技术 2024年第1期52卷 288-296页

作者：马宏伟周文剑王鹏张烨赵英杰王赛赛李烺西安科技大学机械工程学院陕西西安710054 陕西省矿山机电装备智能检测与控制重点实验室陕西西安710054

针对煤矸石分拣机器人分拣煤矸石时,带式输送机输送带打滑、跑偏以及带速波动造成的目标煤矸石位姿变化,从而导致抓取失败或空抓漏抓等问题,提出了一种改进的ORB-FLANN (Oriented FAST and Rotated BRIEF-Fast Library for Approximate ... 详细信息

针对煤矸石分拣机器人分拣煤矸石时,带式输送机输送带打滑、跑偏以及带速波动造成的目标煤矸石位姿变化,从而导致抓取失败或空抓漏抓等问题,提出了一种改进的ORB-FLANN (Oriented FAST and Rotated BRIEF-Fast Library for Approximate Nearest Neighbors)煤矸石识别图像与分拣图像高效匹配方法。提出改进ORB的特征点检测方法对煤矸石识别图像与分拣图像进行特征点检测,实现快速检测图像特征点;提出改进FLANN匹配算法对图像特征点进行匹配,实现煤矸石识别图像与分拣图像高效匹配。针对传统ORB方法对煤矸石图像特征检测时间长、重复率低问题,提出了改进ORB特征检测方法,提高了图像特征点检测速度和重复率;针对传统FLANN匹配方法对煤矸石图像匹配精确率低问题,提出了融合PROSAC算法的改进FLANN匹配方法,剔除错误特征匹配点对,提高了图像匹配的精确率。在自主研发的双机械臂桁架式煤矸石分拣机器人试验平台上应用文中方法、SURF特征匹配方法、HU不变矩匹配方法、SIFT特征匹配方法和ORB特征匹配方法分别进行了不同带速、尺度、旋转角度条件下的煤矸石匹配试验,结果表明:本方法的匹配率为98.2%,匹配时间为141 ms,具有匹配率高、实时性好以及鲁棒性强等特点,能够满足煤矸石识别图像与分拣图像高效精准匹配的要求。

关键词：煤矸石分拣机器人煤矸石识别图像煤矸石分拣图像特征检测特征匹配

Electron-deficient Cu site catalyzed acetylene hydrochlorination

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Green Energy & Environment 2023年第4期8卷 1128-1140页

作者： Bolin wang Chunxiao Jin Shujuan Shao Yuxue Yue Yuteng Zhang saisai wang Renqin Chang Haifeng Zhang Jia Zhao Xiaonian Li School of Chemical Engineering Northeast Electric Power UniversityJilin132012China Industrial Catalysis Institute of Zhejiang University of Technology Hangzhou310014China Research Center of Analysis Measurement Zhejiang University of TechnologyHangzhou310014China

Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by controlling the impregnation solutions. The π electrons flowing from acetylene to Cu site are facilitated over the electron-deficient Cu sites, achieving high activation of C≡C bond. The contradiction between the increased activation of acetylene required for enhanced catalytic activity and the resistance of Cu site to reduction by acetylene required for maintaining catalytic stability can be balanced by establishing strong interactions of Cu site with pyrrolic-N species. The catalytic activity displays a volcano shape scaling relationship as a function of Cu particle size. Tribasic copper chloride is concomitantly generated with the construction of electron-deficient Cu sites. The H–Cl bond of HCl can be activated over the tribasic copper chloride, accelerating the surface reaction of vinyl chloride production. This strategy of inducing electron deficiency provides new insight into the rational design of catalysts for the synthesis of vinyl chloride with a high catalytic performance.

关键词： C≡C bond Acetylene hydrochlorination Cu sites Tribasic copper chloride Electron-deficient

Stabilizing supported gold catalysts in acetylene hydrochlorination by constructing an acetylene–deficient reaction phase

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Green Energy & Environment 2021年第1期6卷 9-14页

作者： Bolin wang Yuxue Yue saisai wang Shujuan Shao Zhi Chen Xianhua Fang Xiangxue Pang Zhiyan Pan Jia Zhao Xiaonian Li Industrial Catalysis Institute of Zhejiang University of Technology Hangzhou310014China Department of Environmental Engineering Zhejiang University of TechnologyHangzhou310014China

In the process of acetylene hydrochlorination,the rapid deactivation of supported gold(Au)catalysts by acetylene is still a huge ***,we provide an innovative strategy for constructing an acetylene–deficient reaction phase on the active site by coating an ionic liquid film on the Au(H2O)/C *** reactant ratio of C2H2 to HCl in this acetylene–deficient reaction phase is 1:132,in contrast to the 1:1 M ratio in the gas phase,thus boosting the catalytic stability of Au(H2O)/C *** kinetic and theoretical analysis showed that the reduction of cationic gold by C2H2 and the generation of carbon deposition can be inhibited in this constructed reaction phase during *** current work not only broadens the scope of supported Au catalysts in acetylene hydrochlorination,but also verifies the perspective of the tunability of stoichiometric balance,which can be used in other catalytic applications.

关键词： Supported Au catalysts Acetylene-deficient Reaction phase Acetylene hydrochlorination