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Docetaxel-loaded liposomes: preparation, pH sensitivity,Pharmacokinetics, and tissue distribution

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第12期13卷 981-989页

作者： hong ZHANG Rui-ying LI Xia LU Zhen-zhen mou Gui-mei LIN School of Pharmaceutical Science Shandong UniversityJinan 250012China

Docetaxel (DTX), as a member of taxoid family, has been widely used in the treatment of cancers. The present study prepared pH-sensitive DTX-loaded liposomes (DTX-Lips) by thin-film dispersion method and various physico-chemical and morphological properties were examined. The pH sensitivity of in vitro DTX release and the in vivo pharmacokinetics and tissue distribution using Kunming mice were also investigated. The mean particle size and zetapotential of DTX liposomes were (277±2) nm and (-32.60±0.26) mV, respectively. Additionally, in vitro drug release study showed that the cumulative release rate was 1.3 times more at pH 5.0 than at pH 7.4, suggesting a pH-dependent releaseability of DTX-Lips. Pharmacokinetic and pharmaceutical studies in comparison with Duopafei showed that the half-timeperiod (t1/2) and area under the curve (AUC) of DTX-Lips in mouse plasma were 1.8 times longer and 2.6 times higher,respectively, and that DTX-Lips selectively accumulated in macrophage-rich organs such as liver and spleen. The seresults together suggest that the DTX-Lips could be a promising formulation for the clinical administration of DTX.

关键词： Docetaxel-loaded liposomes pH sensitivity Pharmacokinetics Tissue distribution

Rheological model of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration treatment

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Rare Metals 2022年第8期41卷 2783-2788页

作者： Yuan-Sheng Rao hong Yan jun Wan Department of Materials Processing Engineering School of Mechanical and Electrical EngineeringNanchang UniversityNanchang330031China Key Laboratory of Light Alloy Preparation and Processing in Nanchang City Nanchang330031China

The rheological behavior of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration treatment was *** effects of primaryα-Mg solid content,the ultrasonic power and the content of reinforcement phase Mg_(2)Si on the apparent viscosity of semisolid composites were *** results show that the apparent viscosity of the semis olid composites increases with the increase in a-Mg solid ***,the apparent viscosity decreases with the increase in ultrasonic power,and the reduction amplitude is higher when the solid content is *** addition,the apparent viscosity increases with the increase in Mg_(2)Si *** on experimental data fitting,the rheological model of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration was established.

关键词： Semisolid Magnesium matrix composites Ultrasonic vibration Apparent viscosity

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论习近平文化思想引领新时代科技文化建设

齐齐哈尔大学学报(哲学社会科学版) 2025年第1期 1-5,16页

作者：张自军蒋红雨黑龙江大学马克思主义学院黑龙江哈尔滨150080 黑龙江大学哲学学院黑龙江哈尔滨150080

科技文化作为人类在认识自然与改造自然过程中积淀形成的特殊文化现象,其本质是创新文化,对赋能新质生产力、推动科技强国建设具有重要作用。习近平文化思想是新时代党领导文化建设实践经验的理论总结,为新时代科技文化建设提供了根本... 详细信息

科技文化作为人类在认识自然与改造自然过程中积淀形成的特殊文化现象,其本质是创新文化,对赋能新质生产力、推动科技强国建设具有重要作用。习近平文化思想是新时代党领导文化建设实践经验的理论总结,为新时代科技文化建设提供了根本遵循。文章聚焦于习近平文化思想文化自信、开放包容、守正创新的方法论意蕴,指出新时代科技文化建设要以彰显中国特色、实现与时偕行、永续发展动力为基本原则,以厚植科技创新的精神沃土、推进科技文化的人文回归、实现科技价值的和谐统一为价值指向,为建设具有中国特色、时代特征、民族特点的科技文化体系提供理论参考与实践路径。

关键词：习近平文化思想科技文化科技创新

Effects of operating parameters on the flow field in slab continuous casting molds with narrow widths

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 238-248页

作者： Tao Zhang Jian Yang Gang-jun Xu hong-jun Liu jun-jun Zhou Wei Qin State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China Hunan Valin Lianyuan Iron&Steel Co. Ltd.Loudi 417000China

Computational simulations and high-temperature measurements of velocities near the surface of a mold were carried out by using the rod deflection method to study the effects of various operating parameters on the flow field in slab continuous casting(CC)molds with narrow widths for the production of automobile exposed *** agreement between the calculated results and measured subsurface velocities of liquid steel was obtained under different operating parameters of the CC *** simulation results reveal that the flow field in the horizontal plane located 50 mm from the meniscus can be used as the characteristic flow field to optimize the flow field of molten steel in the *** in casting speed can increase the subsurface velocity of molten steel and shift the position of the vortex core downward in the downward circulation *** flow field of liquid steel in a 1040 mm-wide slab CC mold can be improved by an Ar gas flow rate of 7 L·min^−1 and casting speed of 1.7 m·min^−*** the present experimental conditions,the double-roll flow pattern is generally stable at a submerged entry nozzle immersion depth of 170 mm.

关键词： flow field rod deflection method continuous casting narrow width numerical simulation operating parameters

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改进YOLOv8M的水下目标检测算法

计算机技术与发展 2025年第1期35卷 30-37页

作者：全文君骆红涛重庆理工大学计算机科学与工程学院重庆400054

受限于水中检测设备内存欠缺和计算能力不够强大以及水下环境错综复杂等多类因素,水下目标检测会出现检测目标错误和漏检目标等问题。为了解决上述问题,通过对YOLOv8M算法进行改进,提出了一种更高效、精准的算法,使水下目标检测检测性... 详细信息

受限于水中检测设备内存欠缺和计算能力不够强大以及水下环境错综复杂等多类因素,水下目标检测会出现检测目标错误和漏检目标等问题。为了解决上述问题,通过对YOLOv8M算法进行改进,提出了一种更高效、精准的算法,使水下目标检测检测性能得到了一定提升。首先,将一种注意力机制(A Simple-Atten Module,SimAM)嵌入网络结构中的颈部,解决了现有注意力模块只能沿着通道或空间维度细化特征,限制学习跨通道和空间变化的注意力权重灵活性的问题,加快了权重计算,提高了模型在水下模糊环境下的检测精度;其次,采用DCNv4(Deformable Convolution v4)可变形卷积替换C2f结构中的3×3卷积模块,以增强空间聚合的动态特性和表达能力并优化内存访问提高速度。此外,还采用加权双向特征金字塔结构(Bidirectional Feature Pyramid Network,BiFPN)将深度的特征信息层进行多尺度特征融合,以增强骨干网络的特征提取能力;最后,在预测部分使用Wise-Inner-MPDIoU损失函数将交叉熵损失函数进行替代,使模型对不同目标及尺寸的自适应能力得到一定程度的提升,增强算法的鲁棒性。从实验结果可以看出,模型经过改进后在URPC2020数据集上取得了86.4的mAP,相比于原始的YOLOv8M算法,mAP提高了2.8百分点,检测速度提升至102.9 FPS。经过改进后算法模型在进行水下目标检测任务时,无论是检测的精度或者速度都得到了有效的改进,说明该算法在用于水下目标检测的实际场景中有一定的实用性。

关键词： YOLOv8M 水下目标检测注意力机制金字塔结构可变形卷积损失函数

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Unraveling role of double-exchange interaction in electrochemical water oxidation by external magnetic field

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Rare Metals 2024年第1期43卷 289-297页

作者： jun Li jun-Ming Li hong hong Dong-Xue Liu Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology Nanjing UniversityNanjing 210093China School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

Double-exchange(DE) interaction plays an important role in electrocatalytic oxygen evolution reaction(OER).However,precise achievement of DE interaction often requires foreign dopants or vacancy engineering,leading to destabilization of the catalysts and deterioration of *** contrast,the utilization of environmentally friendly,contactless,and continuously adjustable magnetic fields to study the OER process is profitable to avoid aforementioned interference factors and further elucidate the direct relationship_(0.5)between DE interaction and OER ***,by using cobalt hydroxide carbonate(Co(OH)(CO_(3))·xH_(2)O,CoHC) nanostructures as a proof-of-concept study,external magnetic fields are carefully implemented to verify the role of DE interaction during water oxidation *** studies reveal that external magnetic fields effectively enhance the reaction rate of the catalyst,the overpotential decreases from 386 to 355 mV(100 mA·cm^(-2)),while Tafel slopes drastically decline from 93 to 67 mV·dec^(-1)(1.0 T).Moreover,magnetic field increment exhibits robust *** in situ Raman and impedance measurements under external field,it can be found that magnetic field promotes the electron migration between Co^(2+) and Co^(3+) in the CoHC catalysts with the assistance of DE interactions,thus boosting the OER efficiency.

关键词： Magnetic field Double-exchange(DE)interaction Electrocatalysis Oxygen evolution reaction(OER) Cobalt hydroxide carbonate

MemSC： A Scan-Resistant and Compact Cache Replacement Framework for Memory-Based Key-Value Cache Systems

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Journal of Computer Science & Technology 2017年第1期32卷 55-67页

作者： Mei Li hong-jun Zhang Yan-jun Wu Chen Zhao National Engineering Research Center of Fundamental Software Institute of Software Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China

Memory-based key-value cache systems, such as Memcached and Redis, have become indispensable components of data center infrastructures and have been used to cache performance-critical data to avoid expensive back-end database accesses. As the memory is usually not large enough to hold all the items, cache replacement must be performed to evict some cached items to make room for the newly coming items when there is no free space. Many real-world workloads target small items and have frequent bursts of scans （a scan is a sequence of one-time access requests）. The commonly used LRU policy does not work well under such workloads since LRU needs a large amount of metadata and tends to discard hot items with scans. Small decreases in hit ratio can result in large end-to-end losses in these systems. This paper presents MemSC, which is a scan-resistant and compact cache replacement framework for Memcached. MemSC assigns a multi-granularity reference flag for each item, which requires only a few bits （two bits are enough for general use） per item to support scanresistant cache replacement policies. To evaluate MemSC, we implement three representative cache replacement policies （MemSC-HM, MemSC-LH, and MemSC-LF） on MemSC and test them using various workloads. The experimental results show that MemSC outperforms prior techniques. Compared with the optimized LRU policy in Memcached, MemSC-LH reduces the cache miss ratio and the memory usage of the resulting system by up to 23% and 14% respectively.

关键词： key-value cache system cache replacement scan resistance space efficiency

Flow Uniformity of Roller-Type Quenching Machine

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Journal of Iron and Steel Research International 2010年第7期17卷 24-27页

作者： ZHU Dong-mei LIU Guo-yong ZHANG Shao-jun LI mou-wei School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China

Three-dimensional finite element flow field model of spraying pipe of roller-type quenching machine is *** flow field with different structural parameters is *** grouping the nozzles,the spraying uniformity is analyzed under the conditions of different water inlet pipe diameter,different water inlet pipe distance,nozzle diameter and nozzle *** the spraying intensity absolute deviation and relative deviation are computed under different *** effect of different structural parameters on cooling uniformity is *** results provide theoretical basis for improving production quality and optimizing cooling device design.

关键词： roller-type quenching machine uniform cooling structural parameter

Sliding Mode Control for Flexible-link Manipulators Based on Adaptive Neural Networks

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International Journal of Automation and computing 2018年第2期15卷 239-248页

作者： hong-jun Yang Min Tan State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences

This paper mainly focuses on designing a sliding mode boundary controller for a single flexible-link manipulator based on adaptive radial basis function （RBF） neural network. The flexible manipulator in this paper is considered to be an Euler-Bernoulli beam. We first obtain a partial differential equation （PDE） model of single-link flexible manipulator by using Hamiltons approach. To improve the control robustness, the system uncertainties including modeling uncertainties and external disturbances are compensated by an adaptive neural approximator. Then, a sliding mode control method is designed to drive the joint to a desired position and rapidly suppress vibration on the beam. The stability of the closed-loop system is validated by using Lyapunov＇s method based on infinite dimensional model, avoiding problems such as control spillovers caused by traditional finite dimensional truncated models. This novel controller only requires measuring the boundary information, which facilitates implementation in engineering practice. Favorable performance of the closed-loop system is demonstrated by numerical simulations.

关键词： Sliding mode control adaptive control neural network flexible manipulator partial differential equation (PDE).