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磁性Ce-La-MOFs@Fe_(3)O_(4)的除氟性能

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材料导报 2024年第4期38卷 38-44页

作者：宋江燕翟涛温倩周融融杨为森简绍菊潘文斌胡家朋福州大学环境与安全工程学院福州350001 武夷学院生态与资源工程学院福建省生态产业绿色技术重点实验室福建武夷山354300 武夷学院数学与计算机学院福建武夷山354300

通过水热法制备了Ce-La-MOFs@Fe_(3)O_(4)复合材料,研究了Ce-La-MOFs@Fe_(3)O_(4)对水溶液中F^(-)的吸附性能,并通过响应曲面法优化了吸附条件。实验结果表明:在pH=3.6、实验温度为40℃、初始氟离子浓度为17.4 mg/L的条件下,Ce-La-MOFs@... 详细信息

通过水热法制备了Ce-La-MOFs@Fe_(3)O_(4)复合材料,研究了Ce-La-MOFs@Fe_(3)O_(4)对水溶液中F^(-)的吸附性能,并通过响应曲面法优化了吸附条件。实验结果表明:在pH=3.6、实验温度为40℃、初始氟离子浓度为17.4 mg/L的条件下,Ce-La-MOFs@Fe_(3)O_(4)的吸附效果最佳,F^(-)去除率可达94.5%。除氟特性实验数据更适合用Langmuir模型进行描述,拟合得到最大吸附容量(q_(max))为147.23 mg/g,热力学参数ΔG^(o)、ΔH^(o)和ΔS^(o)表明该吸附反应是一个自发吸热的熵增过程。动力学研究表明Ce-La-MOFs@Fe_(3)O_(4)对F^(-)的吸附符合准二级反应动力学过程。对复合材料的形貌和结构进行了表征分析,并结合吸附热力学和动力学研究探讨了吸附机理,该吸附过程主要是离子交换和静电吸附共同作用。共存离子实验、循环再生实验结果显示,Ce-La-MOFs@Fe_(3)O_(4)对F^(-)具有较好的选择性,该复合材料的再生性能较好,回收率可达96%,两次循环后对F^(-)的去除率仍达81.74%。

关键词：磁性Ce-La-MOFs@Fe_(3)O_(4) 除氟吸附响应曲面优化

Morphology and structure of BzK-selected galaxies at z ～ 2 in the CANDELS-COSMOS field

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Research in Astronomy and Astrophysics 2015年第6期15卷 819-827页

作者： Guan-wen Fang zhong-yang Ma yang Chen Xu Kong Institute for Astronomy and History of Science and Technology Dali University Key Laboratory for Research in Galaxies and Cosmology University of Science and Technology of China Chinese Academy of Sciences Center for Astrophysics University of Science and Technology of China SISSA via Bonomea 265 I-34136 Trieste Italy

Utilizing a BzK-selecfion technique, we obtain 14 550 star-forming galaxies （sBzKs） and 1763 passive galaxies （pBzKs） at z - 2 from the K-selected （KAB 〈 22.5） catalog in the COSMOS/UltraVISTA field. The differential number counts of sBzKs and pBzKs are consistent with the results from the literature. Compared to the observed results, semi-analytic models of galaxy formation and evolution provide too few （many） galaxies at the high （low） mass end. Moreover, we find that the star formation rate and stellar mass of sBzKs follow the relation of the main sequence. Based on HST/Wide Field Camera 3 F160W imaging, we find a wide range of morphological diversities for sBzKs, from diffuse to early-type spiral structures, with relatively high M20, large size and low G, while pBzKs have elliptical-like compact morphologies with lower M20, smaller size and higher G, indicating a more concentrated and symmetric spatial extent of stellar population distribution in pBzKs than sBzKs. Furthermore, the sizes of pBzKs （sBzKs） at z - 2 are on average two to three （one to two） times smaller than those of local early-type （late-type） galaxies with similar stellar mass. Our findings imply that the two classes have different evolution models and mass assembly histories.

关键词： galaxies evolution -- galaxies fundamental parameters -- galaxies structure -- galaxies high-redshift

玄云SW120B航空发动机尾流热流场数值分析

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重庆理工大学学报（自然科学） 2024年第2期38卷 109-116页

作者：龚淼黄文中国民航大学航空工程学院天津300300

以玄云SW120B航空发动机为研究对象,在纯气相作用和发动机慢车状态下,对尾部热流场进行建模和数值模拟,通过分析尾部温度场和流场特性,得到温度和流速的分布及变化规律。在喷口端面中心建立坐标系,研究结果显示:尾流出口处热流的温度和... 详细信息

以玄云SW120B航空发动机为研究对象,在纯气相作用和发动机慢车状态下,对尾部热流场进行建模和数值模拟,通过分析尾部温度场和流场特性,得到温度和流速的分布及变化规律。在喷口端面中心建立坐标系,研究结果显示:尾流出口处热流的温度和流速呈三维锥体分布,以喷口为中心向外扩散,流体远离喷口0.6 m处开始呈现偏离中心轴向的趋势。尾流高温区域为:zz>2.5 m,y>0.6 m,最高温度不超过323 K。尾流高流速区域为:zz>0.9 m,y>0.2 m,最高流速不超过20 m/s。人体安全区距离为:z>2.5 m,y>0.5 m。研究方法可为大型民航发动机尾流热流场分析和发动机慢车下的地面除冰作业安全区域划分提供参考。

关键词：航空发动机慢车除冰热流场尾流

Quantum secure direct communication with cluster states

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1271-1275页

作者： CAO WeiFeng yang YuGuang wen QiaoYan College of Electric and Information Engineering Zhengzhou University of Light IndustryZhengzhou 450002China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China College of Computer Science and Technology Beijing University of TechnologyBeijing 100124China State Key Laboratory of Integrated Services Network Xidian UniversityXi’an 710071China State key Laboratory of Information Security Gradute University of Chinese Academy of Sciences Beijing 100049China

A quantum secure direct communication protocol with cluster states is *** with the deterministic secure quantum communication protocol with the cluster state proposed by Yuan and Song(***.,2009,7:689),this protocol ca... 详细信息

关键词： quantum secure direct communication deterministic secure quantum communication cluster state

Threshold Multiparty Controlled Teleportation of Arbitrary m-Qubit Quantum Information

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Communications in Theoretical Physics 2009年第10期52卷 593-596页

作者： yang Yu-Guang wen Qiao-Yan College of Computer Science and Technology Beijing University of Technology Beijing 100124 China State Key Laboratory of Integrated Services Network Xidian University Xi＇an 710071 China State Key Laboratory of Information Security （Graduate University of Chinese Academy of Sciences） Beijing 100049 China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

We present a （t, .n） threshold multiparty controlled quantum teleportation protocol of an arbitrary m-qubit quantum state between two remote parties. The unknown m-qubit quantum state can be recovered by the receiver under control of a subset of the n controllers if the number of the subset is larger than or equal to a threshold, say, t, but not for any t - 1 or fewer controllers. Our scheme seems to be more practical and more flexible than other existing protocols. The quantum resource required is just m Einstein-Podolsky-Rosen （EPR） pairs plus some single photons. The techniques required are only Bell state measurement, single-qubit unitary operation and yon Neumann measurement. So our scheme is also feasible with present-day technique.

关键词： controlled teleportation threshold controlled teleportation entanglement

Morphology and structure of extremely red objects at z ～ 1 in the CANDELS-COSMOS field

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Research in Astronomy and Astrophysics 2015年第6期15卷 811-818页

Using high-resolution HST/Wide Field Camera 3 F125W imaging from the CANDELS-COSMOS field, we report the structural and morphological properties of extremely red objects （EROs） at -z 1. Based on the UVJ color criteria, we sepa- rate EROs into two types： old passive galaxies （OGs） and dusty star-forming galaxies （DGs）. For a given stellar mass, we find that the mean size of OGs （DGs） is smaller by a factor of - 2 （1.5） than that of present-day early-type （late-type） galaxies at a rest-frame optical wavelength. We derive the average effective radii of OGs and DGs, corresponding to 2.09 ± 1.13 kpc and 3.27± 1.14 kpc, respectively. Generally, the DGs are heterogeneous, with mixed features including bulges, disks and irregular structures, with relatively high M20, large size and low G. By contrast, OGs have elliptical-like compact morphologies with lower M20, smaller size and higher G, indicating a more concentrated and symmetric spatial extent of the stellar population distribution in OGs than DGs. These findings imply that OGs and DGs have different evolutionary processes, and that the minor merger scenario is the most likely mechanism for the structural properties of OGs. However, the size evolution of DGs is possibly due to the secular evolution of galaxies.

关键词： galaxies evolution -- galaxies: fundamental parameters -- galaxies structure -- galaxies high-redshift

Discovery of six high-redshift quasars with the Lijiang 2.4 m telescope and the Multiple Mirror Telescope

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Research in Astronomy and Astrophysics 2012年第9期12卷 1185-1190页

作者： Xue-Bing Wu wen-wen zuo Qian yang Wei-Min Yi Chen-Wei yang wen-Juan Liu Peng Jiang Xin-wen Shu Hong-Yan zhou Department of Astronomy Peking University Beijing 100871 China wuxb @*** National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy ofSciences Kunming 650011 China Key Laboratory for Research in Galaxies and Cosmology The University of Science andTechnology of China Chinese Academy of Sciences Hefei 230026 China Polar Research Institute of China Shanghai 200136 China

Quasars with redshifts greater than 4 are rare, and can be used to probe the structure and evolution of the early universe. Here we report the discovery of six new quasars with i-band magnitudes brighter than 19.5 and redshifts between 2.4 and 4.6 from spectroscopy with the Yunnan Faint Object Spectrograph and Camera (YFOSC) at the Lijiang 2.4 m telescope in February, 2012. These quasars are in the list of z > 3.6 quasar candidates selected by using our proposed J K/i Y criterion and the photometric redshift estimations from the SDSS optical and UKIDSS near-IR photometric data. Nine candidates were observed by YFOSC, and five among six new quasars were identified as z > 3.6 quasars. One of the other three objects was identified as a star and the other two were unidentified due to the lower signal-to-noise ratio of their spectra. This is the first time that z > 4 quasars have been discovered using a telescope in China. Thanks to the Chinese Telescope Access Program (TAP), the redshift of 4.6 for one of these quasars was confirmed by the Multiple Mirror Telescope (MMT) Red Channel spectroscopy. The continuum and emission line properties of these six quasars, as well as their central black hole masses and Eddington ratios, were obtained.

关键词： quasars: general — quasars: emission lines — galaxies: active — galax- ies: high-redshift

Giant molecules:where chemistry,physics,and bio-science meet

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Science China Chemistry 2017年第3期60卷 338-352页

作者： Guang-zhong Yin wen-Bin zhang Stephen z.D. Cheng Key Laboratory of Polymer Chemistry & Physics of Ministry of Education Center for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Polymer Engineering The University of Akron

This feature article focuses on the recent development of giant molecules,which has emerged at the interface among chemistry,physics,and *** molecular designs are inspired by natural polymers like proteins and are modularly constructed from molecular nanoparticle building blocks via sequential "click" *** important molecular parameters such as topology,composition,and molecular weight can be precisely *** hierarchical assembly reveals many features reminiscent of both small molecules and proteins yet unusual for conventional synthetic *** features are summarized and compared along with synthetic polymers and ***,examples are given in each category of giant molecules to illustrate the characteristics of their hierarchical assembly across different length,time and energy *** idea of "artificial domain" is presented in analogy to the structural domains in *** doing so,we aim to develop a rational and modular approach toward functional *** factors that dominate the materials functions are discussed with respect to the precision and dynamics of the *** complexity of structure-function relationship is acknowledged,which suggests that there is still a long way to go toward the convergence of synthetic polymers and biopolymers.

关键词： giant molecules molecular nanoparticles protein protein engineering domains

Regulatory mechanisms of retinal ganglion cell death in normal tension glaucoma and potential therapies

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Neural Regeneration Research 2023年第1期18卷 87-93页

作者： wen-Cui Shen Bing-Qing Huang Jin yang Tianjin Eye Hospital&Eye Institute Tianjin Key Laboratory of Ophthalmology and Visual ScienceNankai UniversityTianjinChina State Key Laboratory of Experimental Hematology National Clinical Research Center for Blood DiseasesInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjinChina

Normal tension glaucoma(NTG)is a multifactorial optic neuropathy characterized by normal intraocular pressure,progressive retinal ganglion cell(RGC)death,and glaucomatous visual field *** studies have described the mechanisms underlying the pathogenesis of *** addition to controlling intraocular pressure,neuroprotection and reduction of RGC degeneration may be beneficial therapies for *** this review,we summarized the main regulatory mechanisms of RGC death in NTG,including autophagy,glutamate neurotoxicity,oxidative stress,neuroinflammation,immunity,and *** can be induced by retinal hypoxia and axonal *** this process,ischemia can cause mutations of optineurin and activate the nuclear factor-kappa B *** neurotoxicity is induced by the over-stimulation of N-methyl-D-aspartate membrane receptors by glutamate,which occurs in RGCs and induces progressive glaucomatous optic *** stress also participates in NTG-related glaucomatous optic *** impairs the mitochondrial and DNA function of RGCs through the apoptosis signal-regulating kinase-JUN N-terminal kinase ***,it increases inflammation and the immune response of *** 1 causes endothelial dysfunction and impairment of ocular blood flow,promoting vasospasm and glaucomatous optic neuropathy,as a result of *** conclusion,we discussed research progress on potential options for the protection of RGCs,including TANK binding kinase 1 inhibitors regulating autophagy,N-methyl-D-aspartate receptor antagonists inhibiting glutamate toxicity,ASK1 inhibitors regulating mitochondrial function,and antioxidants inhibiting oxidative *** NTG,RGC death is regulated by a network of mechanisms,while various potential targets protect ***,these findings provide insight into the pathogenesis of NTG and potential therapeutic strategies.

关键词： autophagy endothelin 1 glutamate neurotoxicity inhibitor nerve regeneration neuroinflammation normal tension glaucoma oxidative stress retinal ganglion cell vasoconstriction