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Journal of University of Science and Technology Beijing 2008年第6期15卷 723-728页

作者： ying Tang Hongsheng guo School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China Research Institute Beijing No.1 Machine Tool Plant Beijing 101300 China

The paper discussed cutter-work engagement situation hidden behind the mechanical and thermal load effect on cutting edges during high speed hard machining process. The engagement situation was investigated in great detail using experimental and geometrical analytic measures. Experiments were conducted using A1TiN-coated micro-grain carbide end mill cutters to cut hardened die steel. On the basis, a general high speed hard machining strategy, which aimed at eliminating excessive engagement situation during high-speed machining （HSM） hard machining, was proposed. The strategy includes the procedures to identify prone-to-overload areas where excessive engagement situation occurs and then to create a reliable tool path, which has the effect of cutting load reduction to remove the prone-to-overload areas.

关键词： high-speed machining (HSM) hard machining die/mold manufacturing tool path generation load reduction

阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜的制备与表征

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中国组织工程研究 2025年第22期29卷 4720-4730页

作者：胡晨姜莹陈佳乔光伟董文马坚宁夏医科大学总医院口腔颌面外科宁夏回族自治区银川市750004 徐州市口腔医院口腔颌面外科江苏省徐州市221000 宁夏医科大学总医院口腔医院正畸科宁夏回族自治区银川市750004

背景:骨质疏松症是牙种植治疗的高风险因素,制备缓释阿仑膦酸钠的组织工程支架应用于骨质疏松患者口腔种植手术是当前口腔骨组织工程研究热点。目的:制备阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜,表征其缓释性能。方法:(1)采用物理交联... 详细信息

背景:骨质疏松症是牙种植治疗的高风险因素,制备缓释阿仑膦酸钠的组织工程支架应用于骨质疏松患者口腔种植手术是当前口腔骨组织工程研究热点。目的:制备阿仑膦酸钠/壳聚糖/聚乙烯醇复合水凝胶膜,表征其缓释性能。方法:(1)采用物理交联法制备不同质量比(壳聚糖与聚乙烯醇的质量比分别为3∶7、5∶5、7∶3)的壳聚糖/聚乙烯醇复合水凝胶膜与单纯的壳聚糖、聚乙烯醇水凝胶膜,通过表征水凝胶膜的形貌、水接触角、力学性能、溶胀率与细胞相容性筛选适宜的水凝胶膜作为阿仑膦酸钠的载体。(2)制备含0,0.4,1.2,2.0 mg/L阿仑膦酸钠的单纯壳聚糖/聚乙烯醇复合水凝胶膜,将大鼠骨髓间充质干细胞分别与4组水凝胶膜共培养,通过CCK-8法与CD44免疫荧光染色检测水凝胶膜的细胞相容性。将载药壳聚糖/聚乙烯醇复合水凝胶膜浸泡于PBS中,采用紫外可见分光光度法检测复合水凝胶膜的药物释放性能。结果与结论:(1)表征结果显示,随着水凝胶膜中聚乙烯醇质量的增加,水凝胶膜的结构密度增加、孔隙率减少,水接触角(均在90°以内)、断裂伸长率与抗压强度增大,平衡溶胀率降低,对大鼠骨髓间充质干细胞的增殖均无影响,单纯壳聚糖水凝胶膜可促进大鼠骨髓间充质干细胞的黏附,3∶7、5∶5比例复合水凝胶膜不影响大鼠骨髓间充质干细胞的黏附,单纯聚乙烯醇水凝胶膜、7∶3比例复合水凝胶膜抑制大鼠骨髓间充质干细胞的黏附,综合以上结果,选择5∶5复合水凝胶膜作为阿仑膦酸钠的载体。(2)CCK-8检测结果显示,含0.4,1.2 mg/L阿仑膦酸钠组复合水凝胶膜无细胞毒性;CD44免疫荧光染色结果显示,含0.4 mg/L阿仑膦酸钠组复合水凝胶膜不影响大鼠骨髓间充质干细胞的黏附,含1.2,2.0 mg/L阿仑膦酸钠组复合水凝胶膜抑制大鼠骨髓间充质干细胞的黏附;含0.4,1.2,2.0 mg/L阿仑膦酸钠的壳聚糖/聚乙烯醇复合水凝胶膜在最初6 h内爆发性释放阿仑膦酸钠,此后均匀稳定地释放阿仑膦酸钠,释放时间达96 h以上。(3)结果表明,5∶5比例的壳聚糖/聚乙烯醇复合水凝胶膜具有良好的理化性能、细胞相容性,可以作为阿仑膦酸钠的缓释载体。

关键词：阿仑膦酸钠壳聚糖聚乙烯醇水凝胶复合水凝胶膜种植体

Prediction of the geological indicators in TBM tunnel based on optimized proportion of surrounding rock grades

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Underground Space 2023年第4期11卷 204-217页

作者： Xiao guo Wei guo Jianqin Liu Jinli qiao Guisong Hu School of Mechanical Engineering Tianjin UniversityTianjin 300350China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300350China School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China

With tunnel boring machine being used in underground engineering,accurate geological indicators have been the important basis for tunnel boring machine(TBM)*** propagation neural network(BPNN)has been used to predict the geological indicators of tunnels in previous ***,these studies ignored the imbalance proportion of surrounding rock grades,leading to the indiscriminate use of data,thus affecting the predictive effect of *** order to prove the importance of the proportion of surround-ing rock grade in geological prediction,we mainly attempt to utilize particle swarm optimization(PSO)to optimize the proportion of sample data,and integrate with BPNN to establish a PSO-BPNN theoretical model to predict geological *** the same time,combined with the actual engineering data,5 tunneling indicators were selected as input and 4 geological indicators were selected as out-put by a variety of dimensionality reduction *** geological indicators are density,uniaxial compressive strength,internal fric-tion angle(u)and Poisson’s ratio(e).On this basis,the PSO-BPNN prediction model was established in *** comparing the prediction of traditional BPNN,PSO-BPNN and other optimization-integrated models,the result shows that optimized proportion of surrounding rock grades reduces the prediction error and improves the interpretability of the prediction ***,we com-bined the theory of surrounding rock partition to illustrate the rationality of surrounding rock proportion in PSO result,that is,the proportion of complex surrounding rock should be increased appropriately to improve the prediction ***,based on the optimization-integrated models with engineering data and the surrounding rock classification theory,the importance of proportion of surrounding rock grades for tunnel geological prediction is confirmed.

关键词： TBM BPNN Particle swarm optimization Prediction of geological indicators Sample imbalance

Self-templated nitrogen-doped mesoporous carbon decorated with double transition-metal active sites for enhanced oxygen electrode catalysis

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Rare Metals 2020年第7期39卷 824-833页

作者： Meng-Fei qiao ying Wang Lei Li Guang-Zhi Hu guo-An Zou Xamxikamar Mamat Ye-Min Dong Xun Hu Key Laboratory of Chemistry of Plant Resources in Arid Regions Xinjiang Technical Institute of Physics and ChemistryChinese Academy of ScienceUrumqi 830011China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxing 314001China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Material Science and Engineering University of JinanJinan 250022China

The development of high-performance,low-cost bifunctional catalysts with long-term stability for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is one of the most critical challenges for the large-scale application of metal-air ***,we report an advanced nitrogen-doped mesoporous carbon(NMC)composite(NiCo2O4/CoNx-NMC)formed from a mixture of Co-and Ni-hydroxide-infiltrated phenolic resin and melamine *** composite exhibits superior electrocatalytic activity,stability,and selectivity for the ORR and *** activity parameter(DE),which is an indicator of the overall catalytic activity of bifunctional catalysts,was 0.76 V for NiCo2O4/***,catalyst outperforms the majority of previously reported non-precious metal-based bifunctional *** remarkable ultra-high catalytic performance of NiCo2O4/CoNx-NMC for the ORR and OER can be attributed to the presence of different active sites of the CoNx structure and the formation of NiCo2O4 with the spinel structure,which was obtained by a stepwise pyrolysis *** synthesis strategy opens a new avenue for the rational design of highly active bifunctional electrocatalysts.

关键词： Bifunctional catalysis Oxygen reduction reaction Oxygen evolution reaction Pyrolysis strategy Double active sites

Loess-soil sequences in southern Anhui Province: Magnetostratigraphy and paleoclimatic significance

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Chinese Science Bulletin 2003年第19期48卷 2088-2093页

作者： qiao Yansong guo Zhengtang Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029 China SKLLQG Institute of Farth Environment Chinese Academy of Sciences Xi'an 710075 China

Two parallel loess-soil sequences from Xuancheng and Fanchang in southern Anhui Province are dated using geomagnetic and luminescence methods. The Brunhes/Matuyama (B/M) reversal boundary is recognized within the lower part of the so-called Vermiculated Red Soil (VRS) in the Xuancheng section while the entire Fanchang sequence is of Brunhes age. This indicates that the most recent VRS in southern China, a stratigraphic marker and an indication of extremely warm-humid conditions, was formed during the middle Pleistocene, chronologically correlative with the S4 and S5 soil units in northern China. Microscopic and sedimentologic investigations reveal that eolian deposition started in this region at about 0.85 MaBP, roughly synchronous with the well-known Mid-Pleistocene climate change of global significance. The strengthening of both summer and winter monsoon circulations and the consequent river hydrological changes at that time would have provided favorable conditions for sustained eolian deposition in the middle-lower reaches of the Yangtze River since 0.85 MaBP.

关键词：黄土性土壤安徽磁性地层学古气候虫蛀状红土风积物

Molecular recognition and biological application of modified β-cyclodextrins

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Science China Chemistry 2019年第5期62卷 549-560页

作者： ying-Ming Zhang qiao-Yan Xu Yu Liu College of Chemistry State Key Laboratory of Elemento-Organic ChemistryNankai University Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

The molecular recognition based on cyclodextrins(CDs) has become a focus of interest in modern supramolecular *** are known to encapsulate various ions and organic/inorganic molecules in their hydrophobic cavities and form stable inclusion complexes through cooperative noncovalent interactions. During the past few decades, a large variety of modified CDs have been elaborately designed and synthesized, which significantly promotes our molecular-level understanding of the structure–function relationship in many supramolecular systems. Through the accurate analysis on the molecular binding behaviors, one can create a library of CD-based nanoassemblies with controlled physicochemical properties. In this review, we will focus on the stability constant-directed molecular recognition and the biological activities of β-CDs toward some representative bioactive substrates, including metal ions, steroids, porphyrins, amino acids and oligopeptides, as well as drug molecules, with the final goal of promoting their practical applications in the biomedical field.

关键词： Host-guest chemistry molecular recognition cyclodextrin biological function

Adaptive candidate estimation-assisted multi-objective particle swarm optimization

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Science China(Technological Sciences) 2022年第8期65卷 1685-1699页

作者： HAN HongGui ZHANG LinLin HOU ying qiao JunFei Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing 100124China Engineering Research Center of Digital Community Ministry of EducationBeijing 100124China

The selection of global best(Gbest) exerts a high influence on the searching performance of multi-objective particle swarm optimization algorithm(MOPSO). The candidates of MOPSO in external archive are always estimated to select Gbest. However,in most estimation methods, the candidates are considered as the Gbest in a fixed way, which is difficult to adapt to varying evolutionary requirements for balance between convergence and diversity of MOPSO. To deal with this problem, an adaptive candidate estimation-assisted MOPSO(ACE-MOPSO) is proposed in this paper. First, the evolutionary state information,including both the global dominance information and global distribution information of non-dominated solutions, is introduced to describe the evolutionary states to extract the evolutionary requirements. Second, an adaptive candidate estimation method,based on two evaluation distances, is developed to select the excellent leader for balancing convergence and diversity during the dynamic evolutionary process. Third, a leader mutation strategy, using the elite local search(ELS), is devised to select Gbest to improve the searching ability of ACE-MOPSO. Fourth, the convergence analysis is given to prove the theoretical validity of ACE-MOPSO. Finally, this proposed algorithm is compared with popular algorithms on twenty-four benchmark functions. The results demonstrate that ACE-MOPSO has advanced performance in both convergence and diversity.

关键词： multi-objective particle swarm optimization evolutionary state information adaptive candidate estimation convergence and diversity convergence analysis

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Polymers with tertiary amine groups for drug delivery and bioimaging

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Science China Chemistry 2016年第8期59卷 991-1002页

作者： Yu-Juan Gao Zeng-ying qiao Hao Wang CAS Center for Excellence in Nanoscience CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Techr ology Beijing 100190 China

Over the past decade, biopolymers have gained great interests especially in biomedicine due to their physical properties and/or chemical structures changes in response to external stimuli in a certain time fiarne or at a specific location. Among them, poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups have been extensively studied and exhibit pH sensitive properties due to the protonation of tertiary amine groups. The pH values in normal organs, tissues, and subcellular compartments are always different from those in pathological tissues. These interesting properties allow their applications in a variety of fields ranging from diagnosis and therapeutics of diseases. Here, we review the recent progress of poly（β-amino ester）s, methacrylate-based block copolymers and polypeptide with tertiary amine groups and their applications in drug delivery and bioimaging.

关键词： biopolymers tertiary amine groups pH-responsive drug delivery bioimaging

Quantum non-demolition phonon counter with a hybrid optomechnical system

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Science China(Physics,Mechanics & Astronomy) 2018年第5期61卷 1-9页

作者： qiao Song KeYe Zhang ying Dong WeiPing Zhang Quantum Institute for Light and Atoms School of Physics and Material Science East China Normal University Shanghai 200241 China Institute for Quantum Computing and Department of Physics and Astronomy University of Waterloo Waterloo Ontario N2L 3G1 Canada Department of Physics and Astronomy Shanghai Jiao Tong University and Tsung-Dao Lee Institute Shanghai 200240 China Collaborative Innovation Center of Extreme Optics Shanxi University Taiyuan 030006 China

A phonon counting scheme based on the control of polaritons in an optomechanical system is proposed. This approach permits us to measure the number of phonons in a quantum non-demolition(QND) manner for arbitrary modes not limited by the frequency matching condition as in usual photon-phonon scattering detections. The performance on phonon number transfer and quantum state transfer of the counter are analyzed and simulated numerically by taking into account all relevant sources of noise.

关键词： phonon counting optomechanics quantum non-demolition quantum hybrid system

Surface coal mining impacts on land use change and ecological service value:a case study in Shengli coalfield,Inner Mongolia

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International Journal of Coal Science & Technology 2022年第5期9卷 172-186页

作者： Lijia Zhang Xu Zhou Yan Zhou Ji Zhou Jiwang guo Zihan Zhai Yan Chen Xiangyan Su Lingxiao ying Liwei Wang ying qiao China University of Mining and Technology Beijing 100083China Land Consolidation and Rehabilitation Center Ministry of Natural ResourcesBeijing 100035China Zhejiang University Zhejiang 310007China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Coal plays a crucial role in global economic development and remains the most common and widely distributed fossil fuel *** the world's largest developing country,China's mining and utilization of coal resources have contributed signifcantly to the country’s rapid economic *** Mongolia is an ecologically fragile arid and semi-arid area of *** exploitation of opencast mining has seriously hindered the sustainable use of regional land and the residents'*** ENVI-based remote sensing images from 2000,2005,2010,2015,and 2020,this study employed a random forest algorithm to divide land utilization types into construction land,vegetation,cultivated land,bare land,and water areas and analyzed the characteristics of land use and ecosystem service value changes over the past 20 *** results were as follows:(1)Construction land in the mining area changed minimally from 2000 to 2020;vegetation and water bodies showed a decreasing trend,whereas bare and cultivated lands showed an increasing *** land exhibited the largest change in area proportion and water bodies the smallest.(2)The total ecosystem service value of the mining area declined from 10.939 to 9.527 billion *** ecosystem service value was the highest,followed by cultivated land and water,with the bare land ecosystem service value the lowest.(3)On a spatial scale,the total ecosystem service value of the Shengli mining area decreased year by year,indicating that land use changes in the mining area do have an impact on ecosystem service value.

关键词： ESV Land use change Transformed matrix Spatial and temporal change