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振动与冲击 2023年第20期42卷 293-299页

作者：陈宇谢明亮景旭文邹晓峰刘金锋闫德俊江苏科技大学机械工程学院江苏镇江212100 中船黄埔文冲船舶有限公司广东省舰船先进焊接技术企业重点实验室广州510720

为研究齿轮间接触碰撞及啮合间隙等对舰炮随动系统性能及振动特性的影响,建立了考虑齿轮啮合、随动系统等多非线性因素的舰炮机电液耦合动力学模型。其中,基于改进的Lankarani-Nikravesh接触算法及齿轮间时变啮合刚度计算方法,建立了考... 详细信息

为研究齿轮间接触碰撞及啮合间隙等对舰炮随动系统性能及振动特性的影响,建立了考虑齿轮啮合、随动系统等多非线性因素的舰炮机电液耦合动力学模型。其中,基于改进的Lankarani-Nikravesh接触算法及齿轮间时变啮合刚度计算方法,建立了考虑时变啮合刚度的齿轮传动多体接触动力学模型。数值计算结果表明,随动系统中齿轮啮合会使舰炮的振动频率变高,降低随动系统的控制性能,但比例积分微分(proportional-integral-derivative,PID)控制器可在一定程度上抑制齿轮间接触非线性的不利影响。该研究可为舰炮炮控性能的预测和优化提高提供参考。

关键词：舰炮随动系统齿轮啮合间隙接触动力学仿真

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Light and temperature dual responsive pesticide release system based on mesoporous silica nanoparticles modified by dopamine

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Journal of Central South University 2022年第2期29卷 397-409页

作者： xuwen-shuang YANG Zhou-xiao-shuang ZHANG Guang-yang liu Hui Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China Yongzhou Vocational Technical College Yongzhou 425100China

A light and temperature dual responsive copolymer,poly(7-(4-vinylbenzy-loxyl)-4-methylcoumarin-co-N vinyl caprolactam-co-tri(ethylene glycol)methyl ether methacrylate)(PVNM),was grafted on the surface of dopamine based mesoporous silica nanoparticles(MSNs).The resulting polymer brush,MSNs-g-PVNM,was characterized by FT-IR,TEM,TGA and *** dual responsive behaviors of MSNs-g-PVNM were systematically *** imidacloprid as the model guest pesticide,the loading percentage and loading efficiency of the polymer brush were determined as 9.2%and 40.6%,*** release efficiency of imidacloprid in MSNs-g-PVNM was the lowest value of 5.4%at 20℃ and 365 nm,and it reached the highest value of 52.4%at 50℃ and 254 *** loss percentage of imidacloprid on the leaves contained imidacloprid-loaded MSNs-g-PVNM(8.4%)was much less than that contained only imidacloprid(25.2%)after three *** was confirmed that the release process of imidacloprid was well regulated through changing external conditions such as light and temperature.

关键词： N-vinylcaprolactam controlled release system stimuli-responsive mesoporous silica nanoparticles imidacloprid

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Fetal growth prediction: Establishing fetal growth prediction curves in the second trimester

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TECHNOLOGY AND HEALTH CARE 2021年第1_suppl期29卷 S345-S350页

作者： Wang, Yan Bao, Xinyu Zhang, Song Yang, Lin liu, Guoli Yang, Yimin Li, xuwen Hao, Dongmei Chen, Aiqing liu, Xiaohong Shao, Jing Peking Univ Peoples Hosp Beijing 100044 Peoples R China Beijing Univ Technol Fac Environm & Life Sci Beijing 100124 Peoples R China Beijing Int Sci & Technol Cooperat Base Intellige Beijing 100124 Peoples R China Beijing Yes Med Devices Co Ltd Beijing 100152 Peoples R China

BACKGROUND: Monitoring fetal weight during pregnancy has a guiding role in prenatal care. OBJECTIVE: To establish a personalized fetal growth curve for effectively monitoring fetal growth during pregnancy. METHODS: (1) This study retrospectively analyzed the birth weight database of 2,474 singleton newborns delivered normally at term. The personalized fetal growth curve model was formed by combining the estimating birth weight of newborns with the proportional weight formula. (2) Multiple linear stepwise regression method was used to estimate the birth weight of newborns. RESULTS: (1) Delivery gestational age, weight at first visit, maternal height, pre-pregnancy body mass index, fetal sex, parity had significant effects on birth weight. Based on these parameters, the formula for calculating term optimal weight was obtained (R-2 = 22.8%, P < 0.001). (2) The personalized fetal growth curve was obtained according to the epidemiological factors input model of each pregnant woman. CONCLUSIONS: A model of personalized fetal growth curve can be established, and be used to evaluate fetal growth and development through estimated fetal weight monitoring.

关键词： Fetal weight growth charts personal health services

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Assessing the prognostic impact of prostatic urethra involvement and developing a nomogram for T1 stage bladder cancer

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BMC UROLOGY 2023年第1期23卷 182-182页

作者： Wan, Hao Zhan, Xiangpeng Li, xuwen Chen, Tao Deng, Xinxi liu, Yang Deng, Jun Fu, Bin Li, Yu Nanchang Univ Dept Urol Affiliated Hosp 1 Nanchang Jiangxi Peoples R China Nanchang Univ Dept Cardiol Affiliated Hosp 2 Nanchang Jiangxi Peoples R China Jiu Jiang NO1 Peoples Hosp Dept Urol Jiujiang Jiangxi Peoples R China

Purpose To investigate prognostic values of prostatic urethra involvement (PUI) and construct a prognostic model that estimates the probability of cancer-specific survival for T1 bladder cancer patients. Method and materials We investigated the national Surveillance, Epidemiology, and End Results (SEER) database (2004-2015) to get patients diagnosed with T1 bladder cancer. An external validation cohort was obtained from the First Affiliated Hospital of Nanchang University. The Kaplan-Meier method with the log-rank test was applied to assess cancer-specific survival (CSS) and overall survival (OS). Moreover, the propensity score matching (PSM) and multivariable Cox proportional hazard model were performed. All patients were randomly divided into the development cohort and validation group at the ratio of 7:3. The performance of the model was internally validated by calibration curves and the concordance index (C-index). Results The PUI group had a lower survival rate of both CSS and overall survival OS before and after PSM when compared to non-involved patients (All P < 0.05). Multivariate analysis revealed a poor prognosis in the PUI group for cancer-specific mortality (CSM) and all-cause mortality (ACM) analyses before and after PSM (All P < 0.05). Seven variables, including age, surgery, radiotherapy, tumour size, PUI, and marital status, were incorporated in the final nomogram. The C-index in the development cohort was 0.715 (0.711-0.719), while it was 0.672 (0.667-0.677) in the validation group. Calibration plots for 3- and 5-year cancer-specific survival showed good concordance in the development and validation cohorts. Conclusions PUI was an independent risk factor of ACM and CSM in T1 bladder cancer patients. In addition, a highly discriminative and precise nomogram that predicted the individualized probability of cancer-specific survival for patients with T1 bladder cancer was constructed.

关键词： Prognosis T1 bladder cancer Prostatic urethra involved SEER Nomogram

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Submarine Continental Slopes Stability Prediction of Natural Gas HydratesBased on Machine Learning

Submarine Continental Slopes Stability Prediction of Natural...

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Offshore Technology Conference, OTC 2025

作者： Chen, Yu He, Yufa Wang, Yixuan Zhou, Yunjian Fu, Qiang Qin, xuwen liu, Dingyuan Tian, Zheng Zhang, Kexin CNOOC Research Institute Ltd State Key Laboratory of Offshore Natural Gas Hydrates Beijing China Huairou Laboratory Beijing China China Aero Geophysical Survey and Remote Sensing Center for Natural Resources Beijing China

ISBN: (纸本)9781959025610

In the process of extracting naturally-occurring oceanic gas hydrates, the dissociation of hydrates can causea reduction in soil strength. This reduction has the potential to trigger slope failure and submarine landslides,which present a catastrophic threat to offshore facilities and hydrate production. This research aims to create a robust and accurate machine-learning model that can efficiently predict stability of submarine continental slopes where gas hydrates are widespread. By collecting and analyzing 144 relevant cases, a comprehensive dataset was constructed, incorporating slope basic data, overlying and underlying layer data, and geological parameters of the hydrate layer. After conducting a correlation coefficient analysis between the characteristic parameters of the dataset and the output, the key characteristic parameters were determined. To model the dataset and assess its performance, four machine learning techniques were employed: Random Forest(RF), XGBoost, K-Nearest Neighbors (KNN), and Support Vector Machine (SVM). Formation physical parameters, geotechnical parameters, and NGH parameters were taken as input parameters, and the stability of NGH slopes was taken as prediction indicator. Evaluation metrics such as the ROC and confusion matrix were employed to comprehensively evaluate these models’ classification ability. Among these algorithms,the RF algorithm achieves the best prediction accuracy and AUC value, demonstrating its potential in submarine continental slopes stability prediction of natural gas hydrates. Additionally, sensitive analysis using Gini impurity calculations revealed that hydrate decomposition degree is the most significant factor affecting slope stability, followed by the burial depth and thickness of the hydrate layer. The slope angle,cohesion, and internal friction angle also have significant impacts. This study provides a new perspective for predicting submarine continental slopes stability with NGH and offers a scientific

关键词： Landslides

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基于CiteSpace的黑茶研究现状可视化分析

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食品工业科技 2024年第8期45卷 397-406页

作者：张旭雯刘岁赵锦琦杨亚葛炳钢王坤波傅冬和湖南农业大学茶学教育部重点实验室湖南长沙410128 国家植物功能成分利用工程技术研究中心湖南长沙410128 湖南省植物功能成分利用协同创新中心湖南长沙410128 农业农村部园艺作物基因资源评价利用重点实验室湖南长沙410128

黑茶是最受欢迎的茶类之一,为梳理黑茶研究进程,本文利用CiteSpace可视化分析软件,基于中国知网(China national knowledge infrastructure,CNKI)数据库和Web of Science(WOS)数据库核心集合,筛选出的3436篇中文文献和617篇英文文献,对... 详细信息

黑茶是最受欢迎的茶类之一,为梳理黑茶研究进程,本文利用CiteSpace可视化分析软件,基于中国知网(China national knowledge infrastructure,CNKI)数据库和Web of Science(WOS)数据库核心集合,筛选出的3436篇中文文献和617篇英文文献,对作者、关键词、研究机构、国家以及发表期刊等信息进行可视化分析。结果表明,黑茶文献数量呈上升趋势,中文研究早于英文研究,正处于高速发展阶段;《福建茶叶》和《Journal of Agricultural and Food Chemistry》分别是发表黑茶文献最多的中英文期刊;黑茶研究形成了多个研究团体,学者代表有刘仲华、吕才有、周红杰等;研究机构主要为各大农业院校和茶叶研究所,其中,研究成果较深入的机构是云南农业大学、湖南农业大学和安徽农业大学;黑茶研究领域中,我国是影响力最大的国家,其次为美国和日本;中文研究侧重于黑茶品质形成机理、微生物、香气成分等方面,英文研究更关注黑茶的药理研究。黑茶对糖尿病、动脉粥样硬化等代谢疾病的干预功效研究仍是未来国内外研究的热点。

关键词：黑茶 CiteSpace 文献计量学科学知识图谱

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Single-Atom Fe-Anchored Nano-Diamond With Enhanced Dual-Enzyme Mimicking Performance for H2O2 and Glutathione Detection

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FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY 2022年 9卷 790849页

作者： liu, Ying Yan, Jianghong Huang, Yu Sun, Zhiheng Zhang, Huijing Fu, Lihaoyuan Li, xuwen Jin, Yongri Jilin Univ Coll Chem Changchun Peoples R China First Clin Hosp Jilin Prov Acad Tradit Chinese Med Changchun Peoples R China

Glutathione (GSH) is an important antioxidant and free radical scavenger that converts harmful toxins into harmless substances and excretes them out of the body. In the present study, we successfully prepared single-atom iron oxide-nanoparticle (Fe-NP)-modified nanodiamonds (NDs) named Fe-NDs via a one-pot in situ reduction method. This nanozyme functionally mimics two major enzymes, namely, peroxidase and oxidase. Accordingly, a colorimetric sensing platform was designed to detect hydrogen peroxide (H2O2) and GSH. Owing to their peroxidase-like activity, Fe-NDs can oxidize colorless 3,3 ',5,5 '-tetramethylbenzidine (TMB) into blue with sufficient linearity at H2O2 concentrations of 1-60 mu M and with a detection limit of 0.3 mu M. Furthermore, using different concentrations of GSH, oxidized TMB can be reduced to TMB, and the color change from blue to nearly colorless can be observed by the naked eye (linear range, 1-25 mu M;detection limit, 0.072 mu M). The established colorimetric method based on oxidase-like activity can be successfully used to detect reduced GSH in tablets and injections with good selectivity and high sensitivity. The results of this study exhibited reliable consistency with the detection results obtained using high-performance liquid chromatography (HPLC). Therefore, the Fe-NDs colorimetric sensor designed in this study offers adequate accuracy and sensitivity.

关键词： nanodiamond single-atom Fe peroxidase-like and oxidase-like activity colorimetric sensor glutathione

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Probing the surface forces between air bubbles and bitumen via direct force Measurements: Effects of aqueous chemistry

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FUEL 2024年第PartC期357卷

作者： Yang, Diling Qiao, Chenyu Mao, Xiaohui Wang, Jingyi Xie, Lei Chen, Jingsi Peng, xuwen Peng, Qiongyao Wang, Tao liu, Qi Zhang, Hao Zeng, Hongbo Univ Alberta Dept Chem & Mat Engn Edmonton AB T6G 1H9 Canada

The surface interactions of air bubbles and other components (e.g., particles, oil droplets) significantly influence the operation efficiency of a variety of engineering processes such as oily water treatment, bitumen extraction and flotation. Herein, the surface interactions of air bubbles with two types of Athabasca bitumen samples in aqueous solutions of varying pH, salinity, type of cations and in the presence of surfactants have been systematically characterized using a bubble probe atomic force microscope (AFM) technique. AFM imaging has revealed that exposure to high concentrations of NaCl and CaCl2 solutions or alkaline environments causes roughening of the bitumen surfaces. The results of surface force measurements demonstrate that the interaction and attachment behaviors between bubbles and bitumen are significantly affected by ionic strength, solution pH, and the presence of surfactants. The experimental force measurement results could be accurately described by a theoretical model that incorporates Reynolds lubrication theory and augmented Young-Laplace equation, with the inclusion of disjoining pressure. In low-salinity conditions, the bubble-bitumen interaction is dominated by electric double layer (EDL) repulsion, which prevents surface attachment. This effect is more pronounced at elevated pH conditions. In high-salinity solutions, however, the EDL interactions are significantly reduced, and the hydrophobic interaction becomes the dominant factor, overcoming the van der Waals repulsion and leading to the attachment of bubbles to bitumen surfaces. Raising aqueous pH weakens the bubble-bitumen hydrophobic interaction, whereas the introduction of calcium ions strengthens this interaction, resulting in enhanced surface attachment. Interestingly, even in high-salinity conditions, the presence of a small number of surfactants can inhibit bubble-bitumen contact, mainly caused by reduced hydrophobic attraction and increased steric repulsion. This work provid

关键词： bitumen oil sands bitumen flotation bubbles surface interactions

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Gradient tumor microenvironment-promoted penetrating micelles for hypoxia relief and immunosuppression reversion in pancreatic cancer treatment

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ACTA BIOMATERIALIA 2023年第1期167卷 387-400页

作者： Luo, Yifan Li, Chao Zhang, Yiwen liu, Peixin Chen, Hongyi Zhao, Zhenhao Wang, Yu Zhou, Zheng Song, Haolin Su, Boyu Li, Chufeng Li, xuwen Zhang, Tongyu You, Haoyu Wu, Yuxing Tian, Zonghua Zhang, Shilin Guo, Yun Fan, Hongrui Chen, Qinjun Jiang, Chen Sun, Tao Fudan Univ Minhang Hosp Sch Pharm Dept Pharmaceut Shanghai 201203 Peoples R China Fudan Univ MOE Frontiers Ctr Brain Sci Shanghai 201203 Peoples R China

The tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC) is the main block for the penetration of chemotherapy. In the tumor microenvironment, a dense matrix composed of fibrin is formed on the exterior, while the interior is featured by high reduction, hypoxia and low pH. How to match the special microenvironment to on-demand drug release is the key to improve chemotherapeutic efficacy. Herein, a microenvironment-responsive micellar system is developed to deepen tumoral penetration. Briefly, the conjugation of a fibrin-targeting peptide to PEG-poly amino acid has been utilized to achieve accumulation of micelles in the tumor stroma. By modification of micelles with hypoxia-reducible nitroimidazole which becomes protonated under acidic conditions, their surface charge is more positive, facilitating deeper penetration into tumors. Paclitaxel was loaded onto the micelles via a disulfide bond to enable glutathione (GSH)-responsive release. Therefore, the immunosuppressive microenvironment is relived through the alleviation of hypoxia and depletion of GSH. Hopefully, this work could establish paradigms by designing sophisticated drug-delivery systems to tactfully employ and retroact the tamed tumoral microenvironment to improve the therapeutic efficacy based on understanding the multiple hallmarks and learning the mutual regulation.

关键词： Pancreatic cancer Penetration Nitroimidazole Tumor hypoxia Gemcitabine

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非线性曲面梁形态优化及恒压支撑装置设计

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机械强度 2024年第1期46卷 161-168页

作者：谢苗张文卓李伟东刘杰邹青海邢旭文辽宁工程技术大学机械工程学院华能煤炭技术研究有限公司庆阳新庄煤业有限公司新庄煤矿

基于超前支护设备顶梁支撑结构研究一种恒压支撑装置的设计方法，恒压支撑装置由正刚度线性弹簧、负刚度非线性平面曲梁及承压气囊组合而成。通过对巷道顶板应力场分析，得到支撑结构的边界条件；利用B样条曲线简述负刚度非线性平面曲... 详细信息

基于超前支护设备顶梁支撑结构研究一种恒压支撑装置的设计方法，恒压支撑装置由正刚度线性弹簧、负刚度非线性平面曲梁及承压气囊组合而成。通过对巷道顶板应力场分析，得到支撑结构的边界条件；利用B样条曲线简述负刚度非线性平面曲梁的特点；基于遗传算法与非线性有限元法对负刚度非线性平面曲梁进行形态优化设计；依据恒压支撑装置的工作原理，对线性螺旋弹簧刚度/强度特性进行分析与设计；对恒压支撑装置的零部组件进行设计，实现支撑装置输出压强大小恒定及自我保护功能。恒压支撑装置设计方法为综掘巷道超前支护研制提供了有力技术支撑。

关键词：恒压支撑装置非线性平面曲梁形态优化

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