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Insights into Formation and Li-Storage Mechanisms of Hierarchical Accordion-Shape Orthorhombic CuNb_(2)O_(6) toward Lithium-Ion Capacitors as an Anode-Active Material
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作者 Chao Cheng Yunsheng Yan +3 位作者 Minyu Jia Yang Liu Linrui Hou Changzhou Yuan 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期287-298,共12页
The orthorhombic CuNb_(2)O_(6)(O-CNO)is established as a competitive anode for lithium-ion capacitors(LICs)owing to its attractive compositional/structural merits.However,the high-temperature synthesis(>900℃)and c... The orthorhombic CuNb_(2)O_(6)(O-CNO)is established as a competitive anode for lithium-ion capacitors(LICs)owing to its attractive compositional/structural merits.However,the high-temperature synthesis(>900℃)and controversial charge-storage mechanism always limit its applications.Herein,we develop a low-temperature strategy to fabricate a nano-blocks-constructed hierarchical accordional O-CNO framework by employing multilayered Nb_(2)CT_(x)as the niobium source.The intrinsic stress-induced formation/transformation mechanism of the monoclinic CuNb_(2)O_(6)to O-CNO is tentatively put forward.Furthermore,the integrated phase conversion and solid solution lithium-storage mechanism is reasonably unveiled with comprehensive in(ex)situ characterizations.Thanks to its unique structural merits and lithium-storage process,the resulted O-CNO anode is endowed with a large capacity of 150.3 mAh g^(-1)at 2.0 A g^(-1),along with long-duration cycling behaviors.Furthermore,the constructed O-CNO-based LICs exhibit a high energy(138.9 Wh kg^(-1))and power(4.0 kW kg^(-1))densities with a modest cycling stability(15.8%capacity degradation after 3000 consecutive cycles).More meaningfully,the in-depth insights into the formation and charge-storage process here can promote the extensive development of binary metal Nb-based oxides for advanced LICs. 展开更多
关键词 high-rate anodes lithium-ion capacitors lithium-storage mechanisms orthorhombic CuNb_(2)O_(6) phase transform
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Mechanism of Yanghe Pingchaun granules on airway remodeling in asthmatic rats based on IL-6/JAK2/STAT3 signaling axis
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作者 LV Chuan ZHU Hui-zhi +4 位作者 LIU Xiang-guo CAO Xiao-mei XIA Yong-qi ZHANG Qiu-ping YU Zi-qi 《Journal of Hainan Medical University》 CAS 2024年第1期15-21,共7页
Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(... Objective: To investigate the effects of Yanghe Pingchuan Granules on airway remodeling in asthmatic rats, and to explore the mechanism of Interleukin-6/Janus kinase 2/ Signal transducing activator of transcription 3(IL-6/JAK2/STAT3) signal axis. Methods: We separated 42 healthy male SD rats into two groups, a control group (7) and a model group (35).The model group was sensitized with a combination of ovalbumin (OVA) and aluminum hydroxide for 2 weeks, while the control group was given an equal amount of physiological saline.After 2 weeks, the modeling group was randomly divided into Model group, Yanghe Pingchuan Granules high, medium and low dose groups and Dexamethasone group, each group consisted of 7 animals. After 4 weeks, OVA atomization and gavage were used for stimulation and treatment. Yanghe Pingchuan Granules high, middle and low groups were given 15.48, 7.74, 3.87 g∙kg-1 Yanghe Pingchuan Granules daily, dexamethasone group was given 0.0625 mg∙kg-1 dexamethasone daily, and the other groups were given the same amount of normal saline. HE, PAS and Masson staining were used to observe the lung histopathological changes in rats. The levels of interleukin-6, IL-23 and IL-17A were detected by ELISA. The expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 in lung tissues were detected by Western blot. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the mRNA expression levels of IL-6, JAK2 and STAT3 in rat lung tissue. Results: The lung tissue structure of the model group was severely damaged compared to the control group, accompanied by a great many of inflammatory cell infiltration, goblet cell hyperplasia, subepithelial collagen fiber deposition and airway epithelial thickening were more obvious. The expressions of IL-6, IL- 23 and IL-17A in serum were significantly increased (P<0.01), the protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and the mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly increased (P<0.01);Compared with the model group, inflammatory cell infiltration, goblet cell proliferation, subepithelial collagen fiber deposition and airway epithelial thickening were significantly reduced in each administration group, and the expressions of IL-6, IL-23 and IL-17A in serum were significantly decreased (P< 0.01). The protein expression levels of JAK-2, P-JAK2, STAT3 and P-STAT3 and mRNA expression levels of IL-6, JAK2 and STAT3 in lung tissue were significantly decreased (P<0.01). Conclusion: Yanghe Pingchuan Granules can significantly alleviate airway remodeling in asthmatic rats, and its mechanism may be through inhibiting the IL-6/JAK2/STAT3 signal axis. 展开更多
关键词 Yanghe Pingchuan Granules Interleukin-6/Janus kinase 2/Signal transducing activator of transcription 3(IL-6/JAK2/STAT3)signal axis Asthma Airway remodeling mechanism study
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基于合成数据集的多目标识别与6-DoF位姿估计
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作者 胡广华 欧美彤 李振东 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期42-50,共9页
多目标识别及六自由度(6-DoF)位姿估计是实现物料无序堆放状态下机器人自动分拣的关键。近年来,基于深度神经网络的方法在目标识别及位姿估计领域受到广泛关注,但此类方法依赖大量训练样本,而样本的采集及标注费时费力,限制了其实用性... 多目标识别及六自由度(6-DoF)位姿估计是实现物料无序堆放状态下机器人自动分拣的关键。近年来,基于深度神经网络的方法在目标识别及位姿估计领域受到广泛关注,但此类方法依赖大量训练样本,而样本的采集及标注费时费力,限制了其实用性。其次,当成像条件差、目标相互遮挡时,现有位姿估计方法无法保证结果的可靠性,进而导致抓取失败。为此,文中提出了一种基于合成数据样本的目标识别、分割及位姿估计方法。首先,以目标对象的3维(3D)几何模型为基础,利用3D图形编程工具生成虚拟场景的多视角RGB-D合成图像,并对生成的RGB图像及深度图像分别进行风格迁移和噪声增强,从而提高合成数据的真实感,以适应真实场景的检测需要;接着,利用合成数据集训练YOLOv7-mask实例分割模型,运用真实数据进行测试,结果验证了该方法的有效性;然后,以分割结果为基础,基于ES6D目标位姿估计模型,提出了一种在线姿态评估方法,以自动滤除严重失真的估计结果;最后,采用基于主动视觉的位姿估计校正策略,引导机械臂运动到新的视角重新检测,以解决因遮挡而导致位姿估计偏差的问题。在自行搭建的6自由度工业机器人视觉分拣系统上进行了实验,结果表明,文中提出的方法能较好地适应复杂环境下工件的识别与6-DoF姿态估计要求。 展开更多
关键词 目标识别 位置测量 6-dof位姿估计 机器人自动分拣 RGB-D图像
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6-DOFs机器臂在位置模式下追随运动意图的研究
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作者 刘环宇 陈明祥 +1 位作者 高孟扬 王钰 《科学技术创新》 2024年第1期59-62,共4页
为了使脑卒中患者在主动康复中能够得到准确、实时、稳定的识别效果,本研究提出了基于6-DOFs协作机器人作为一种康复运动设备。患者的运动意图通过其手与机器臂末端的六维力传感器作用的程度与方向来捕捉,控制系统则通过解析出的运动意... 为了使脑卒中患者在主动康复中能够得到准确、实时、稳定的识别效果,本研究提出了基于6-DOFs协作机器人作为一种康复运动设备。患者的运动意图通过其手与机器臂末端的六维力传感器作用的程度与方向来捕捉,控制系统则通过解析出的运动意图实现机器臂末端运动方向与速度的设置和驱动。运动意图主要由运动方向和运动程度两个指标表达,前者由力传感器各分力的合力方向确定,后者由合力的大小确定,同时还要检测合力与TCP所在轨迹点处切线方向的夹角,最终确定出机器臂末端沿轨迹运动的速度。 展开更多
关键词 6-dofs 运动意图 运动控制算法
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Ultrasonic solidification mechanism and optimized application performances of ternary Mg_(71.5)Zn_(26.1)Y_(2.4) alloy
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作者 Y.J.Hu J.Y.Wang +1 位作者 W.Zhai B.Wei 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第10期3829-3839,共11页
One dimensional(1D) and three dimensional(3D) ultrasound sources were applied to the solidification process of Mg_(71.5)Zn_(26.1)Y_(2.4) alloy.The acoustic spectra were in-situ measured, based on which the cavitation ... One dimensional(1D) and three dimensional(3D) ultrasound sources were applied to the solidification process of Mg_(71.5)Zn_(26.1)Y_(2.4) alloy.The acoustic spectra were in-situ measured, based on which the cavitation intensities and dynamic solidification mechanism were further investigated. With the increase of ultrasonic dimension and amplitude, the primary Mg_(3)Zn_(6)Y phase was significantly refined from petals to nearly pentagonal shape. The sound field measurements showed that the transient cavitation played a decisive role in generating a high local undercooling, which facilitated the formation of icosahedral clusters and promoted the nucleation of primary Mg_(3)Zn_(6)Y phase. The morphological transition of(α-Mg+Mg_(3)Zn_(6)Y) eutectic from lamellar to anomalous structure occurred under 3D ultrasonic condition. The stable cavitation took the main responsibility because the high pressure excited by nonlinearly oscillating bubbles induced the preferential nucleation of α-Mg phase rather than Mg_(3)Zn_(6)Y phase. As compared with its static values, the tensile strength and compression plasticity of this alloy were increased by the factors of 1.9 and 2.1, and its corrosion resistance was also improved with the corrosion current density decreased by one order of magnitude. 展开更多
关键词 Three dimensional ultrasounds Quasicrystalline Mg_(3)Zn_(6)Y phase Anomalous eutectic mechanical performances Corrosion resistance
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Topology optimization of a 6-DOF spatial compliant mechanism based on Stewart propotype platform 被引量:3
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作者 Dachang Zhu Wanghu Zhan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第5期1044-1059,共16页
To improve the global stiffness and conveniently build a model of a compliant mechanism with spatial multiple degrees of freedom(DOF),the topology optimization method,combined with the isomorphic mapping matrix,is pro... To improve the global stiffness and conveniently build a model of a compliant mechanism with spatial multiple degrees of freedom(DOF),the topology optimization method,combined with the isomorphic mapping matrix,is proposed in this paper for structure synthesis of a 6-DOF spatial compliant mechanism.By using the differential approximation method,the Jacobian matrix of the Stewart prototype platform is calculated as the isomorphic mapping matrix,and its eigenvalues and eigenvectors are considered.Combining the isomorphic mapping matrix with the solid isotropic material with the penalization topology optimization method,the topological model of the 6-DOF spatial compliant mechanism is constructed,and a topological structure of the 6-DOF spatial compliant mechanism is derived which has the same differential kinematic characteristics as the Gough-Stewart prototype platform.Piezoelectric actuators are mounted inside the topological structure during the three-dimensional printing manufacturing process,and its driver directions are in accordance with the driver configuration directions of the Gough-Stewart prototype platform.The effectiveness of the proposed method for topological structure synthesis of the 6-DOF spatial compliant mechanism is demonstrated through several numerical examples and experimental studies. 展开更多
关键词 6-dof SPATIAL compliant mechanism STEWART prototype PLATFORM ISOMORPHIC mapping JACOBIAN matrix Topology optimization
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Research of 6-DOF Serial-Parallel Mechanism Platform for Stability Training of Legged-Walking Robot 被引量:1
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作者 Wei-Guo Wu Wen-Qian Du 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期75-82,共8页
The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of ... The concept of legged-robot stability training with a training platform is proposed and a serial-parallel mechanism platform with 6 degrees of freedom is designed for this target. The designed platform is composed of 4-DOF parallel mechanism with spherical joints and prismatic pairs,and 2-DOF serial mechanism with prismatic pairs. With this design,the platform has advantages of low platform countertop,big workspace,high carrying capacity and high stiffness. On the basis of DOF analysis and computation of space mechanism,weight supporting auxiliary mechanism and raceways-balls supporting mechanism are designed,so as to improve the stiffness of designed large platform and payload capacity of servo motors. And then the whole structure design work of the platform is done. Meanwhile,this paper derives the analytical solutions of forward kinematics, inverse kinematics and inverse dynamics. The error analysis model of position and orientation is established. And then the simulation is done in ADAMS to ensure the correctness and feasibility of this design. 展开更多
关键词 6-dof serial-parallel mechanism forward kinematics stability training legged-walking robot
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基于赋权偏差传递网络的6Dof-RUS并联机构随机误差分析
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作者 董广宇 杜玉红 杨磊成 《中国惯性技术学报》 EI CSCD 北大核心 2024年第9期948-954,共7页
对于已经完成加工装配高精度并联机构,当出现使用精度无法满足设计要求时,需要对产生误差的源头进行追溯,只修复部分构件提高机构精度。以单点激光测距仪检测方法与六条由转动副(R)虎克铰链(U)球面副(S)构成单支链的6自由度并联机构(6Do... 对于已经完成加工装配高精度并联机构,当出现使用精度无法满足设计要求时,需要对产生误差的源头进行追溯,只修复部分构件提高机构精度。以单点激光测距仪检测方法与六条由转动副(R)虎克铰链(U)球面副(S)构成单支链的6自由度并联机构(6Dof-RUS)随机误差模型之间的映射为研究内容。首先构建了6Dof-RUS并联机构赋权偏差传递网络,其次建立了相机坐标系中光斑与平面约束之间的映射方程,通过结构误差雅可比矩阵将结构参数误差映射为可观测的动平台位姿误差。最后进行了实验验证,实验结果表明,在有限次测量次数的情况下可快速对随机误差进行溯源,验证了所提方法的有效性与可靠性,对其他拓扑构型并联机构精度综合具有一定借鉴意义。 展开更多
关键词 并联机构 随机误差 误差溯源 6自由度并联机构
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超声振动对玻璃纤维增强聚酰胺6注塑制件力学性能的影响
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作者 刘莹 孙昊 +4 位作者 杨勇 姜开宇 于同敏 马赛 祝铁丽 《中国塑料》 CAS CSCD 北大核心 2024年第7期9-14,共6页
为提高纤维增强复合材料的力学性能,对玻璃纤维增强聚酰胺6(PA6/GF)复合材料进行了矩形平板制件超声辅助注射成型实验。通过对制件进行X射线衍射测试、扫描电子显微镜观测、傅里叶红外光谱分析以及拉伸性能测试,研究了超声施加时间和超... 为提高纤维增强复合材料的力学性能,对玻璃纤维增强聚酰胺6(PA6/GF)复合材料进行了矩形平板制件超声辅助注射成型实验。通过对制件进行X射线衍射测试、扫描电子显微镜观测、傅里叶红外光谱分析以及拉伸性能测试,研究了超声施加时间和超声功率对制件的结晶度、玻璃纤维的取向程度、玻璃纤维与基体的结合强度以及制件力学性能的影响;并研究了经过超声振动的制件在吸水后其内部结晶度及力学性能的变化。结果表明,施加400 W超声振动,可以明显提高制件的结晶度;施加560 W超声时,玻璃纤维的取向形态得到改善,纤维与基体的结合强度有所提高,充填阶段施加超声所得制件的拉伸强度与弯曲强度比无超声振动的情形分别提高了11.9%与10.1%;但是如果继续增加超声功率,将会使制件的力学性能开始变差。制件吸水后,结晶度和力学性能下降,对制件的成型引入超声振动则能减小这种下降的幅度。 展开更多
关键词 超声振动 玻璃纤维增强聚酰胺6 凝聚态结构 结晶度 力学性能
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Surlyn树脂改性PA6/CaCl_(2)材料的制备及性能
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作者 李杨 肖臻 +1 位作者 娄文菊 刘伟 《塑料工业》 CAS CSCD 北大核心 2024年第3期41-47,75,共8页
本文通过双螺杆挤出制备了沙林(Surlyn)树脂改性尼龙6(PA6)/CaCl_(2)材料,通过红外光谱(FTIR)、拉曼光谱(Raman)研究了Surlyn树脂改性对复合材料的分子链结构的影响,并通过X射线衍射(XRD)、差示扫描量热仪(DSC)和扫描电镜(SEM)对改性材... 本文通过双螺杆挤出制备了沙林(Surlyn)树脂改性尼龙6(PA6)/CaCl_(2)材料,通过红外光谱(FTIR)、拉曼光谱(Raman)研究了Surlyn树脂改性对复合材料的分子链结构的影响,并通过X射线衍射(XRD)、差示扫描量热仪(DSC)和扫描电镜(SEM)对改性材料的结晶性能和微观结构进行了分析。结果表明,Surlyn树脂能够促使PA6分子链间氢键减弱,但是PA6/CaCl_(2)/Surlyn复合材料的结晶度变化并不明显,改性后复合材料的γ晶型在总结晶度中所占的比例随Surlyn树脂用量的增加而逐渐增大,添加20%质量分数的Surlyn树脂后PA6/CaCl_(2)/Surlyn复合材料结晶度基本不变,但α晶型的比例由38.43%下降至30.52%。加入15%质量分数的Surlyn树脂后PA6/CaCl_(2)/Surlyn复合材料出现了明显的脆-韧转变;添加20%质量分数的Surlyn树脂后复合材料拉伸强度为58.12 MPa,与纯PA6相比复合材料的拉伸强度仅下降10.42%,而断裂伸长率和缺口冲击强度达到152.14%和10.27 kJ/m^(2),分别增加了135.98%和66.72%。 展开更多
关键词 尼龙6 氯化钙 沙林树脂 氢键 力学性能
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白细胞介素6在腰椎间盘突出症中的研究
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作者 李亮 曲俊鹏 郭玲玲 《系统医学》 2024年第16期191-194,共4页
白细胞介素6(interleukin 6,IL-6)是最常见的炎症因子,具有抗炎和促炎的双向性,在炎症反应中发挥着巨大的作用。故其在炎症反应性疾病中具有高表达的特性,腰椎间盘突出可导致局部的炎症反应,造成IL-6的高表达,而IL-6等炎性细胞因子的高... 白细胞介素6(interleukin 6,IL-6)是最常见的炎症因子,具有抗炎和促炎的双向性,在炎症反应中发挥着巨大的作用。故其在炎症反应性疾病中具有高表达的特性,腰椎间盘突出可导致局部的炎症反应,造成IL-6的高表达,而IL-6等炎性细胞因子的高表达可导致痛觉过敏,从而导致椎间盘源性腰痛和神经根疼痛的发生。目前已经有研究提示阻断IL-6/IL-6R轴可以有效的治疗炎症相关的自身免疫性疾病,希望通过干预IL-6的反应过程,阻断局部的炎症反应,有效治疗盘源性腰痛和神经根痛。本文综述了IL-6的炎症反应机制以及对腰椎间盘突出的影响,期以提供腰椎间盘突出靶向药物治疗的部分依据。 展开更多
关键词 白细胞介素6 炎症反应 腰椎间盘突出 机制 靶向药物
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CDK4/6抑制剂在HR^(+)晚期乳腺癌治疗中的耐药机制及进展后治疗策略
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作者 王蕾 杨思原 +1 位作者 张季 聂建云 《中南药学》 CAS 2024年第4期1030-1036,共7页
细胞周期蛋白依赖性激酶4/6(CDK4/6)抑制剂联合内分泌治疗已成为激素受体阳性(HR^(+))、人类表皮生长因子受体-2阴性(HER2^(-))乳腺癌患者的晚期一线及二线标准治疗方案。尽管CDK4/6抑制剂可实现有效的疾病控制,但对于晚期乳腺癌患者最... 细胞周期蛋白依赖性激酶4/6(CDK4/6)抑制剂联合内分泌治疗已成为激素受体阳性(HR^(+))、人类表皮生长因子受体-2阴性(HER2^(-))乳腺癌患者的晚期一线及二线标准治疗方案。尽管CDK4/6抑制剂可实现有效的疾病控制,但对于晚期乳腺癌患者最终仍会因耐药出现疾病进展。目前CDK4/6抑制剂相关耐药机制尚不完全清楚,同时治疗失败后的最佳治疗策略仍是一个亟待解决的问题。本文就CDK4/6抑制剂的潜在耐药机制和后续治疗策略的最新研究进展做一综述。 展开更多
关键词 细胞周期蛋白依赖性激酶4/6抑制剂 乳腺癌 耐药机制 内分泌治疗
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m^(6)A修饰对药物代谢酶和药物转运体的调控作用 被引量:2
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作者 赵世宇 刘帅兵 +1 位作者 王月琴 田鑫 《中国药理学通报》 CAS CSCD 北大核心 2024年第7期1221-1225,共5页
m^(6)A修饰是RNA甲基化修饰中最丰富的一种修饰,受甲基转移酶和去甲基化酶的动态调控,被m^(6)A识别蛋白识别并结合后可影响mRNA的剪切、稳定性和翻译等生物学过程来调控靶基因的表达。最近的研究发现,m^(6)A修饰可通过多种途径来调控药... m^(6)A修饰是RNA甲基化修饰中最丰富的一种修饰,受甲基转移酶和去甲基化酶的动态调控,被m^(6)A识别蛋白识别并结合后可影响mRNA的剪切、稳定性和翻译等生物学过程来调控靶基因的表达。最近的研究发现,m^(6)A修饰可通过多种途径来调控药物代谢酶和药物转运体表达,进而影响机体对药物的代谢速率或影响细胞中的药物浓度,最终导致药物治疗效果发生变化。该文综述了m^(6)A修饰调控药物代谢酶和药物转运体分子机制的研究进展,以期为临床上的合理用药、个体化用药提供新思路。 展开更多
关键词 RNA甲基化 m^(6)A修饰 药物代谢酶 药物转运体 调控机制 研究进展
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Effect of deep cryogenic treatment on the microstructural,mechanical and ballistic properties of AA7075-T6 aluminum alloy 被引量:1
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作者 S.Dharani kumar U.Magarajan +1 位作者 Saurabh S Kumar Rodríguez-Millan M 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期101-110,共10页
The study focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum alloy.The microstructure,microhardness,tensile strength,and impact strengt... The study focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum alloy.The microstructure,microhardness,tensile strength,and impact strength of the Base Material(BM)and DCT-treated 7075 samples were analyzed through metallographic analysis and mechanical tests.The microstructure of the DCT-treated 7075 samples revealed fine grains and a distribution of secondary phase particles.The tensile strength,impact strength,and microhardness of DCT-treated samples increased by 7.41%,4%,and 9.68%,respectively,compared to the BM samples.The fractography analysis of the tensile samples showed cleavage facets,microvoids,and dimples in both the samples.The ballistic behavior of the BM and DCT target plates were studied by impacting hard steel core projectiles at a velocity of 750±10 m/s.The target plates failed due to petaling and ductile hole enlargement,and the depth of penetration(DOP)of the DCT target was less than that of the BM target,indicating a higher ballistic resistance.The post-ballistic microstructure examination of the target plates showed the formation of an Adiabatic Shear Band(ASB)without any cracks.It was concluded that the DCT treatment improved the mechanical and ballistic properties of the aluminum alloy due to grain refinement and high dislocation density. 展开更多
关键词 Deep cryogenic treatment AA7075-T6 mechanical properties BALLISTIC Adiabatic shear band
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基于IL-6/JAK2/STAT3信号轴研究阳和平喘颗粒调控哮喘大鼠气道重塑作用机制 被引量:2
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作者 吕川 朱慧志 +4 位作者 刘向国 曹晓梅 夏咏琪 张秋萍 余子奇 《海南医学院学报》 北大核心 2024年第1期15-20,28,共7页
目的:研究阳和平喘颗粒对哮喘大鼠气道重塑及白细胞介素-6(IL-6)/Janus蛋白酪氨酸激酶2(JAK2)/信号转导和转录活化因子3(STAT3)信号轴在其中的作用机制。方法:选取健康雄性SD大鼠42只,随机数字法分为正常对照组7只与造模组35只,造模组... 目的:研究阳和平喘颗粒对哮喘大鼠气道重塑及白细胞介素-6(IL-6)/Janus蛋白酪氨酸激酶2(JAK2)/信号转导和转录活化因子3(STAT3)信号轴在其中的作用机制。方法:选取健康雄性SD大鼠42只,随机数字法分为正常对照组7只与造模组35只,造模组采用卵清蛋白(OVA)联合氢氧化铝腹腔注射2周的方式进行致敏,正常对照组采用等量的生理盐水;2周后将造模组随机分为模型组、阳和平喘高、中、低剂量组和地塞米松组,每组7只;后4周采用OVA雾化+灌胃的方式进行激发和治疗,阳和平喘高中低组每日分别予以15.48、7.74、3.87 g/kg阳和平喘颗粒灌胃,地塞米松组予以0.0625 mg/kg地塞米松进行灌胃,其余组灌胃等量生理盐水。HE、PAS、Masson染色观察大鼠肺组织病理学变化;ELISA检测大鼠血清中IL-6、IL-23、IL-17A水平;Western blot检测肺组织中JAK-2、P-JAK2、STAT3、P-STAT3蛋白表达量;qRT-PCR检测大鼠肺组织中IL-6、JAK2、STAT3的mRNA水平。结果:与正常对照组比较,模型组大鼠肺组织有大量炎性细胞浸润,杯状细胞增生、上皮下胶原纤维沉积、气道上皮增厚较为明显;血清中IL-6、IL-23、IL-17A水平显著升高(P<0.01),肺组织JAK-2、P-JAK2、STAT3、P-STAT3的蛋白表达量和IL-6、JAK2、STAT3的mRNA表达水平显著升高(P<0.01);与模型组比较,各给药组炎性细胞浸润、杯状细胞增生、上皮下胶原纤维沉积、气道上皮增厚程度明显减轻,血清中IL-6、IL-23、IL-17A水平显著降低(P<0.01),肺组织JAK-2、P-JAK2、STAT3、P-STAT3的蛋白表达量和IL-6、JAK2、STAT3的mRNA水平显著降低(P<0.01)。结论:阳和平喘颗粒可明显缓解哮喘大鼠气道重塑,其机制可能是通过抑制IL-6/JAK2/STAT3信号轴发挥作用。 展开更多
关键词 哮喘 阳和平喘颗粒 气道重塑 IL-6/JAK2/STAT3信号轴 机制研究
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Experimental study on thermal and mechanical properties of tailings-based cemented paste backfill with CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials 被引量:2
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作者 Xiaoyan Zhang Tianrun Cao +3 位作者 Lang Liu Baoyun Bu Yaping Ke Qiangqiang Du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期250-259,共10页
CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the ... CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the CPB with CEV added was prepared,and the specific heat capacity,thermal conductivity,and uniaxial compressive strength(UCS)of CPB with different cement-tailing ratios and CEV addition ratios were tested,the influence of the above variables on the thermal and mechanical properties of CPB was analyzed.The results show that the maximum encapsulation capacity of expanded vermiculite for CaCl_(2)·6H_(2)O is about 60%,and the melting and solidification enthalpies of CEV can reach 98.87 J/g and 97.56 J/g,respectively.For the CPB without CEV,the specific heat capacity,thermal conductivity,and UCS decrease with the decrease of cement-tailing ratio.For the CPB with CEV added,with the increase of CEV addition ratio,the specific heat capacity increases significantly,and the sensible heat storage capacity and latent heat storage capacity can be increased by at least 10.74%and 218.97%respectively after adding 12%CEV.However,the addition of CEV leads to the increase of pores,and the thermal conductivity and UCS both decrease with the increase of CEV addition.When cement-tailing ratio is 1:8 and 6%,9%,and 12%of CEV are added,the 28-days UCS of CPB is less than 1 MPa.Considering the heat storage capacity and cost price of backfill,the recommended proportion scheme of CPB material presents cement-tailing ratio of 1:6 and 12%CEV,and the most recommended heat storage/release temperature cycle range of CPB with added CEV is from 20 to 40℃.This work can provide theoretical basis for the utilization of heat storage backfill in green mines. 展开更多
关键词 CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials cemented paste backfill thermal property mechanical property
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钢背及合金层厚度对ZChSnSb11-6巴氏合金耐磨性的影响 被引量:1
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作者 齐瑾 朱丽慧 +1 位作者 张金鹏 王小静 《上海金属》 CAS 2024年第4期22-27,共6页
利用MFT-500多功能摩擦机对ZSnSb11Cu6(11-6)巴氏合金及采用离心铸造方法在40Cr钢钢背上浇铸的厚度为2.0、2.5 mm的ZChSnSb11-6巴氏合金层进行了摩擦磨损试验,研究了钢背及合金层厚度对巴氏合金耐磨性的影响。结果表明:与无钢背巴氏合... 利用MFT-500多功能摩擦机对ZSnSb11Cu6(11-6)巴氏合金及采用离心铸造方法在40Cr钢钢背上浇铸的厚度为2.0、2.5 mm的ZChSnSb11-6巴氏合金层进行了摩擦磨损试验,研究了钢背及合金层厚度对巴氏合金耐磨性的影响。结果表明:与无钢背巴氏合金相比,有钢背2.5 mm厚巴氏合金的耐磨性提高了26.6%,而2.0 mm厚巴氏合金的耐磨性下降了12.8%。有钢背2.0 mm厚巴氏合金的硬度较高,磨痕和犁沟较浅,但其残余拉应力最大,麻点数量最多、剥落程度最大,耐磨性最差;而2.5 mm厚巴氏合金的麻点数量最少、剥落程度最小,磨痕和犁沟也较浅,耐磨性最好;相较于2.5 mm厚巴氏合金,无钢背巴氏合金的残余拉应力较小,但其硬度最低,磨痕和犁沟最深,麻点数量更多、剥落更严重,耐磨性较差。 展开更多
关键词 ZChSnSb11-6 巴氏合金 耐磨性 磨损机制 硬度 残余应力
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6-DOF机械臂运动学分析和验证 被引量:3
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作者 罗贵成 胡添嗣 《现代机械》 2023年第2期68-73,共6页
为了实现6-DOF机械臂末端的运动控制,利用改进D-H方法推导了机械臂的正运动学齐次变换矩阵,基于齐次变换矩阵,推导出了机械臂的四组运动学逆解,针对运动控制过程中逆解的选取问题,提出了一种基于机械臂初始角的逆解选取方法,并根据解的... 为了实现6-DOF机械臂末端的运动控制,利用改进D-H方法推导了机械臂的正运动学齐次变换矩阵,基于齐次变换矩阵,推导出了机械臂的四组运动学逆解,针对运动控制过程中逆解的选取问题,提出了一种基于机械臂初始角的逆解选取方法,并根据解的特性推导出了初始角的可选范围;通过matlab机器人工具箱仿真验证了机器人正逆解以及逆解选取方法的正确性,利用twincat3-机械臂控制系统进行实验,进一步验证了逆解选取方法的正确有效。 展开更多
关键词 6-dof机械臂 D-H方法 运动学逆解 逆解的选取
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Algebraic Solution for the Forward Displacement Analysis of the General 6-6 Stewart Mechanism 被引量:8
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作者 WEI Feng WEI Shimin +1 位作者 ZHANG Ying LIAO Qizheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期56-62,共7页
The solution for the forward displacement analysis(FDA) of the general 6-6 Stewart mechanism(i.e., the connection points of the moving and fixed platforms are not restricted to lying in a plane) has been extensive... The solution for the forward displacement analysis(FDA) of the general 6-6 Stewart mechanism(i.e., the connection points of the moving and fixed platforms are not restricted to lying in a plane) has been extensively studied, but the efficiency of the solution remains to be effectively addressed. To this end, an algebraic elimination method is proposed for the FDA of the general 6-6 Stewart mechanism. The kinematic constraint equations are built using conformal geometric algebra(CGA). The kinematic constraint equations are transformed by a substitution of variables into seven equations with seven unknown variables. According to the characteristic of anti-symmetric matrices, the aforementioned seven equations can be further transformed into seven equations with four unknown variables by a substitution of variables using the Grobner basis. Its elimination weight is increased through changing the degree of one variable, and sixteen equations with four unknown variables can be obtained using the Grobner basis. A 40th-degree univariate polynomial equation is derived by constructing a relatively small-sized 9 × 9 Sylvester resultant matrix. Finally, two numerical examples are employed to verify the proposed method. The results indicate that the proposed method can effectively improve the efficiency of solution and reduce the computational burden because of the small-sized resultant matrix. 展开更多
关键词 general 6-6 Stewart mechanism forward displacement analysis (FDA) conformal geometric algebra (CGA) Gr6bner basis Sylvester resultant
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原位聚合法制备连续玻璃纤维增强尼龙6复合材料的改性和性能 被引量:1
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作者 冯冰涛 王晓珂 +6 位作者 张萌 殷茂峰 张信 孙国华 马劲松 李鹏鹏 侯连龙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第1期25-33,共9页
尼龙6(PA6)树脂具有优异的性能,其连续纤维复合材料在汽车、航空航天领域具有广泛应用。但是PA6树脂熔融后黏度较高,不易对连续纤维充分浸渍,并且连续纤维与PA6的复合材料界面黏附性较差,限制了其复合材料的性能和应用。针对这些问题,... 尼龙6(PA6)树脂具有优异的性能,其连续纤维复合材料在汽车、航空航天领域具有广泛应用。但是PA6树脂熔融后黏度较高,不易对连续纤维充分浸渍,并且连续纤维与PA6的复合材料界面黏附性较差,限制了其复合材料的性能和应用。针对这些问题,文中对连续玻璃纤维增强尼龙6(CGF/PA6)复合材料开展了研究。首先,采用阴离子开环聚合制备PA6,确定了其最佳制备工艺;其次,用硅烷偶联剂KH550(AP)对连续玻璃纤维(CGF)进行改性,并对其进行了红外光谱表征;最后,通过原位聚合法制备了CGF/PA6复合材料,研究了AP改性对CGF/PA6复合材料力学性能的影响,并对CGF/PA6复合材料的拉伸断口进行了扫描电镜分析。结果表明,AP被键合到了CGF表面,AP改性可以增强CGF/PA6复合材料的界面黏附性,从而使CGF/PA6复合材料的拉伸强度得到改善,当AP用量为2%时,CGF/PA6复合材料的拉伸强度高达88.52 MPa,此时,复合材料的断裂伸长率最低,为4.90%。CGF/PA6复合材料的冲击强度变化不大,均在50 k J/m2左右,说明复合材料的韧性受CGF表面改性影响较小。 展开更多
关键词 原位聚合 连续玻璃纤维 尼龙6 硅烷偶联剂KH550 力学性能
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