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Biophysical-driven piezoelectric and aligned nanofibrous scaffold promotes bone regeneration by re-establishing physiological electrical microenvironment

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Nano Research 2024年第8期17卷 7376-7393页

作者： aoao Wang Xinbo Ma Yafeng Yang Guoliang Shi Liwei Han Xiantong Hu Rui Shi Jun Yan Quanyi Guo Yantao Zhao Senior Department of Orthopedics the Fourth Medical Center of PLA General HospitalBeijing 100048China Department of Chemistry Capital Normal UniversityBeijing 100048China National Center for Orthopaedics Beijing Research Institute of Traumatology and OrthopaedicsBeijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China Xijing 986 Hospital Department The Fourth Military Medical UniversityXi'an 710032China Institute of Orthopedics Chinese PLA General HospitalBeijing Key Laboratory of Regenerative Medicine in OrthopedicsKey Laboratory of Musculoskeletal Trauma&War Injuries PLABeijing 100853China

The initial healing stages of bone fracture is a complex physiological process involving a series of spatially and temporally overlapping events,including pathogen clearance,immunological modulation,and *** this study,we have developed a piezoelectric and aligned nanofibrous scaffold composed of ZnO@PCL/PVDF with multiple antibacterial,immunomodulatory,and osteogenic effects using electrospinning *** scaffold’s piezoelectric signal output under ultrasound(US)control can be similar to the physiological electrical signals of healthy bone tissue,creating a truly biomimetic electrical microenvironment in the bone *** vitro studies have shown that ZnO@PCL/PVDF scaffold significantly enhances the proliferation,migration,and osteogenic differentiation of MC3T3-E1 cells under piezoelectric drive provided by ***,the scaffold exhibits inhibitory effects on the growth of *** and ***,as well as the ability to induce M2.macrophage polarization,indicating potent antibacterial and immunomodulatory *** vivo experiments demonstrated that the ZnO@PCL/PVDF scaffold can accelerate the repair of mandibular defects in rats,effectively inhibit bacterial colonization,and reduce inflammatory ***,this study confirms that the newly developed ZnO@PCL/PVDF scaffold effectively promotes bone repair by truly mimicking the endogenous electrical microenvironment and precisely regulating the temporospatial disorders of initial bone healing,thus providing a simple and effective solution for bone defects.

关键词： piezoelectricity bone defect bacterial infection ZnO nanoparticles immunomodulation osteogenesis

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新型波形钢腹板组合箱梁畸变效应

中国铁道科学 2024年第1期45卷 89-98页

作者：秦翱翱刘世忠马驰贡保甲蔡明昊枣庄学院城市与建筑工程学院山东枣庄277160 兰州交通大学土木工程学院甘肃兰州730070

为研究新型波形钢腹板(CSW)组合箱梁的畸变效应,以板梁框架法和位移法为基础,建立单箱多室新型CSW组合箱梁的畸变控制微分方程和边界条件,得到畸变正应力解析解,并采用有限元法检验推导结果的正确性。应用推导结果对比分析新型CSW组合... 详细信息

为研究新型波形钢腹板(CSW)组合箱梁的畸变效应,以板梁框架法和位移法为基础,建立单箱多室新型CSW组合箱梁的畸变控制微分方程和边界条件,得到畸变正应力解析解,并采用有限元法检验推导结果的正确性。应用推导结果对比分析新型CSW组合箱梁与传统CSW组合箱梁的畸变性能,以及截面高度、箱室宽度和钢底板厚度对新型CSW组合箱梁畸变效应的影响。结果表明:解析解计算得到的畸变正应力与有限元模型计算的结果吻合较好,畸变角的变化规律与有限元模型计算结果一致;与传统CSW组合箱梁相比,新型CSW组合箱梁的畸变翘曲刚度减小了38.89%,畸变框架刚度减小了71.84%,抗畸变能力减弱;随着截面高度和箱室宽度增加,新型CSW组合箱梁跨中畸变角和跨中畸变双力矩均逐渐增大,且箱室宽度的影响更为明显;随着钢底板厚度增加,新型CSW组合箱梁跨中畸变角逐渐减小,跨中畸变双力矩逐渐增大。

关键词：波型钢胶板组合箱梁单箱多室畸变效应畸变控制微分方程边界条件畸变性能

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胶磷矿与白云石界面水化特性的分子模拟研究

有色金属（选矿部分） 2024年第7期 38-47页

作者：陈傲傲张覃贵州大学资源与环境工程学院贵阳550025 贵州科学院贵阳550001 喀斯特地区优势矿产资源高效利用国家地方联合工程实验室贵阳550025 贵州省非金属矿产资源综合利用重点实验室贵阳550025

以胶磷矿为研究对象,研究了胶磷矿和白云石的界面水化特性,通过密度泛函理论(DFT)和分子动力学模拟(MDS)研究了单个水分子在氟磷灰石(001)面和白云石(104)面的吸附构型和水溶液中矿物表面的水化作用,并对矿物界面形成水化膜的结构和性... 详细信息

以胶磷矿为研究对象,研究了胶磷矿和白云石的界面水化特性,通过密度泛函理论(DFT)和分子动力学模拟(MDS)研究了单个水分子在氟磷灰石(001)面和白云石(104)面的吸附构型和水溶液中矿物表面的水化作用,并对矿物界面形成水化膜的结构和性质进行分析。DFT结果表明,水分子会与氟磷灰石(001)面和白云石(104)面发生相互作用,水分子在氟磷灰石表面与Ca1位点的吸附能为-12..19 kJ/mol,在白云石表面与Ca和Mg位点的吸附能为-62.30 kJ/mol和-54.89 kJ/mol,水分子的O与氟磷灰石和白云石表面的Ca/Mg位点作用形成弱化学吸附,水分子与白云石表面Ca位点作用强于Mg位点,水分子的H与两种矿物表面的O作用形成氢键吸附。氟磷灰石/白云石-水体系MDS结果表明,两种矿物表面水分子密度沿z轴方向出现明显分层,靠近矿物表明的水分子密度较大,这层水分子即为水化膜。水化膜内的水分子呈定向、密集排列,氟磷灰石和白云石表面均能形成水化膜。通过相对浓度分布和扩散系数分析发现,氟磷灰石和白云石表面水化膜结构分为有序层、过渡层和本体水,靠近表面的有序层水分子与表面作用较强,水分子有序排列,外层水分子主要受氢键作用,水分子随着与表面距离增加趋于混乱无序,氟磷灰石表面水化膜厚度为0.56 nm,白云石表面水化膜厚度为0.68 nm。

关键词：磷灰石白云石密度泛函理论分子动力学模拟

Coordinated observations of large scale coronal brightening and H_αsurge

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Chinese Science Bulletin 1998年第23期43卷 1969-1973页

作者： Jiong Qiu aoao Xu Department of Astronomy Nanjing Unversity Nanjing China

During the post_flare phase of an eruptive two_ribbon flare on February 4, 1995, the Soft X_ray Telescope (SXT) on board Yohkoh observed the rapid brightening of a set of large scale coronal loops (150-2.0 Mm in length). Simultaneously, coordinated ground_based observations reveal a co_incident H α surge event. To our knowledge, no H α surge event coincident with the large scale coronal brightening observed by Yohkoh has been reported. The possible mechanisms for the concurrent cool plasma ejection and the filling of the hot coronal loops are discussed. It is found that magnetic reconnection between a magnetic arcade and an overlying large scale coronal structure may account for the coincident events. Big amount of magnetic energy was converted into both mechanic energy (about 10 2. J) in the mass ejection and thermal radiation (10 2. J) contained in the large SXR loops.

关键词： Sun: activity Sun flares X_rays coordinated observation.

Solid sand particle addition can enhance the production of resting cysts in dinoflagellates

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Journal of Oceanology and Limnology 2018年第2期36卷 273-280页

作者： YANG aoao HU Zhangxi TANG Yingzhong CASKey Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China University of Chinese Academy of Sciences Beijing 100049 China Laboratory of Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China

Resting cysts are an important part of the life cycle for many harmful algal bloom-forming dinoflagellates, and play vital roles in the recurrence and geographical spread of harmful algal blooms. Numerous factors have been suggested to regulate the formation of resting cysts, although only a few have been proven to be significant. Cyst formation can be induced by adverse environmental conditions such as drastic changes in temperature, light, salinity, and nutrient levels, and by biological interactions. In this study, we evaluated the ability of an artificial factor(fine sand particles) to enhance the formation of resting cysts. Fine sand particles were added to cultures of dinoflagellates that are known to produce cysts. The addition of fine sand particles significantly increased both the production rate and final yield of cysts in cultures of S crippsiella trochoidea, Biecheleria brevisulcata, and Levanderina fissa(= Gymnodinium fissum, Gyrodinium instriatum, Gyr odinium uncatenum). The largest increase in the final yield(107-fold) of cysts as a result of sand addition was in S. trochoidea. However, addition of fine sand particles did not induce cyst formation, or barely af fected cyst formation, in A kashiwo san guinea, Cochlodinium polykrikoides and Pheopolykrikos hartmannii, which are also known to be cyst-producing species. We speculated that addition of sand significantly increased the chances of cell collision, which triggered cyst formation. However, further research is required to test this idea. Importantly, our findings indicate that the addition of fine sand particles is a useful method to obtain a large quantity of cysts in a short time for laboratory studies or tests; for example, if a cyst viability test is being used to assess the eff ectiveness of ships' ballast water treatment.

关键词： sand resting cyst encystment Scrippsiella trochoidea Biecheleria brevisulcata Levanderina fissa

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盐酸环丙沙星对大豆早期生长发育的影响

生物化工 2024年第4期10卷 43-48页

作者：余小壮张燕高大鹏杨傲傲临沂大学生命科学学院山东临沂276000

目的:探究盐酸环丙沙星类抗生素残留对农作物生长发育的毒性作用。方法:设置系列浓度梯度的盐酸环丙沙星,研究其对大豆萌发及其幼苗生长发育的影响。结果:在0~100 mg/L的浓度条件下,大豆种子的发芽率、发芽指数和活力指数均随盐酸环丙... 详细信息

目的:探究盐酸环丙沙星类抗生素残留对农作物生长发育的毒性作用。方法:设置系列浓度梯度的盐酸环丙沙星,研究其对大豆萌发及其幼苗生长发育的影响。结果:在0~100 mg/L的浓度条件下,大豆种子的发芽率、发芽指数和活力指数均随盐酸环丙沙星浓度的增大均呈下降趋势。当盐酸环丙沙星浓度为5 mg/L时,发芽势最高,与对照组相比无显著差异;当盐酸环丙沙星浓度>5 mg/L时,随浓度升高发芽势不断下降。在96 h内,5 mg/L组的大豆总长度均高于其他组,但随着时间延长,大豆总长度随盐酸环丙沙星浓度的升高而降低,其中100 mg/L抑制作用最明显,总长度最短。与对照组相比,大豆幼苗鲜质量和各类叶绿素含量均随盐酸环丙沙星浓度的增大而减少。结论:环境中的高浓度的盐酸环丙沙星会抑制大豆的萌发及早期生长发育。

关键词：盐酸环丙沙星抗生素大豆生长发育叶绿素

Effect and mechanism of reductive polyaniline on the stability of nitrocellulose

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Lunar potassium distribution:Results from Chang'E-1 gamma ray spectrometer

Defence technology 2024年第8期 217页

作者： Wenjiang Li Binbin Wang Huimin Chen aoao Lu Chenguang Li Qiang Li Fengqiang Nan Ping Du

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2083-2090页

作者： ZHU Meng-Hua MA Tao CHANG Jin TANG ZeSheng IP Wing-Huen XU aoao Space Exploration Laboratory Macao University of Science and Technology Avenida Wai Long Taipa Macao China Purple Mountain Observatory Chinese Academy of Sciences 2 West Beijing Road Nanjing 210008 China

The global map of potassium is represented in this paper from Chang'E-1 (CE-1) Gamma-ray Spectrometer (CGRS) for its one-year *** a linear relationship between net count rate and its abundance,the average potassium abundance of individual landing sites is used as ground-truth for the calibration to derive the global map of absolute *** CGRS spectra have a lower signal-to-noise ratio,the translated map still keeps relative *** calculated from Apollo,Lunar Prospector,and Kaguya,global potassium map from CGRS shows high concentrations on the lunar nearside and secondary concentrations located in the South Pole-Aitken (SPA) basin on the *** comparison with Lunar Prospector potassium map shows a good correlation,though abundances on the highlands of the farside are much lower than that of Lunar *** the footprint of CGRS measurements is larger than the sampling radius of each landing site,the calibrated map shows a larger variation range of the scale than that of Lunar Prospector,which was derived using theoretical calculation;namely,the calibrated map has higher values in the areas with high concentration while having lower values for the areas with lower ***,the derived potassium map is more consistent with the lunar sample data than that of Lunar Prospector.

关键词： Chang'E-1 gamma-ray spectrometer potassium distribution empirical calibration

磷矿中磷灰石及脉石矿物浮选表面化学研究进展

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矿产保护与利用 2024年第3期44卷 1-15页

作者：张覃卯松黄小芬陈傲傲张文彬贵州科学院贵州贵阳550001 贵州大学贵州贵阳550025 喀斯特地区优势矿产资源高效利用国家地方联合工程实验室贵州贵阳550025 贵州省非金属矿产资源综合利用重点实验室贵州贵阳550025 昆明理工大学云南昆明650031

磷矿是战略性关键矿产资源。中国磷矿储量位居世界第二位,主要类型为沉积型磷块岩。由于磷块岩是由外生作用形成、由隐晶质或显微隐晶质磷灰石及其它脉石矿物组成的堆积体,并且磷灰石与脉石矿物的表面润湿性、表面电性、表面吸附等表面... 详细信息

磷矿是战略性关键矿产资源。中国磷矿储量位居世界第二位,主要类型为沉积型磷块岩。由于磷块岩是由外生作用形成、由隐晶质或显微隐晶质磷灰石及其它脉石矿物组成的堆积体,并且磷灰石与脉石矿物的表面润湿性、表面电性、表面吸附等表面性质相近,使得浮选分离难度大。浮选表面化学是磷矿浮选的重要理论基础,是实现不同矿物之间选择性分离的关键。综述了磷矿石中主要有用矿物磷灰石和主要脉石矿物白云石、石英的晶体化学特征,以及磷灰石与脉石矿物表面润湿性、表面电性、表面吸附等表面性质。讨论了不同浮选药剂作用下矿物表面润湿性的变化特征、矿物在水溶液中的双电层结构、矿物表面的活性位点与捕收剂作用的吸附构型。在此基础上,总结了难免离子对磷灰石与脉石矿物浮选行为的影响,为中低品位磷矿石的浮选分离提供理论支撑。

关键词：磷灰石白云石石英浮选表面化学晶体化学特征表面性质难免离子