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The Tenth Anniversary of Free Trade Pilot Zones in China:Fundamental Experiences and Enhancement Strategies
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作者 Pei Changhong 《China Economist》 2024年第3期2-20,共19页
Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demo... Since the 18th National Congress of the Communist Party of China,the country has established 21 Free Trade Pilot Zones(FTZs),achieving significant pioneering results in reform and opening up and creating a strong demonstrative effect nationwide.The basic experience from a decade of FTZs includes:adhering to the centralized and unified leadership of the CPC Central Committee;combining top-level design with encouragement of grassroots innovation;leveraging the distinct characteristics and strengths of FTZs to form a differentiated development pattern;maintaining the integration of opening up with domestic reforms;using openness to drive reforms;and organically combining openness with national security assurance.Under the current and future new circumstances,China’s FTZs face new challenges and tasks.In accordance with the directives of the 20th National Congress of the Communist Party of China,an enhancement strategy for the FTZs needs to be implemented.This involves the following:First,accurately understanding and responding to the changing situation to create strategic opportunities.Second,shifting paradigms to implement innovation-driven strategies,using the new development pattern concept to guide the reform experiments and construction of the FTZs.Third,granting more autonomy to FTZs for reforms,pursuing progress while maintaining stability,and solidly advancing the reform experiments in the FTZs.Fourth,orderly expanding the opening up of the service sector and cautiously advancing the internationalization of the renminbi.Fifth,promoting innovative development in trade to build a strong trade nation.Sixth,establishing synergy with bilateral FTZs,Belt and Road cooperation,and national diplomatic strategies to enhance the linkage effect. 展开更多
关键词 Tenth anniversary of free Trade Pilot Zones experience summary enhancement strategy conception
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Experimental Study on Free Spanning Submarine Pipeline Under Dynamic Excitation 被引量:9
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作者 李昕 刘亚坤 +2 位作者 周晶 马恒春 朱彤 《China Ocean Engineering》 SCIE EI 2002年第4期537-548,共12页
Seismic load has a significant effect on the response of a free spanning submarine pipeline when the pipeline is constructed in a seismically active region. The model experiment is performed on an underwater shaking t... Seismic load has a significant effect on the response of a free spanning submarine pipeline when the pipeline is constructed in a seismically active region. The model experiment is performed on an underwater shaking table to simulate the response of submarine pipelines under dynamic input. In consideration of the effects of the terrestrial and submarine pipeline, water depth, support condition, distance from seabed, empty and full pipeline, and span on dynamic response, 120 groups of experiments are conducted. Affecting factors are analyzed and conclusions are drawn for reference. For the control of dynamic response, the span of a submarine pipeline is by far more important than the other factors. Meanwhile, the rosponse difference between a submarine pipeline under sine excitation and that under random excitation exists in experiments. 展开更多
关键词 free spanning submarine pipeline underwater shaking table model experiment dynamic response factor analysis
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Model experiment of rock blasting with single borehole and double free-surface 被引量:5
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作者 TIAN Jian-sheng QU Fan-fei 《Mining Science and Technology》 EI CAS 2009年第3期395-398,404,共5页
In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-... In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-surface was performed with the objective of studying the effect of parameters such as charge structure, free-surface and rock compressive strength on rock blasting.The model experiments indicate that:1) the smaller the rock compressive strength and density, the more distinctive the cavity expanding action by blasting;2) the powder factor in an air-decoupling charge structure is larger than that in a coupling charge structure, i.e., the explosive energy in an air-decoupling charge structure transferred to the rocks is less than that in a coupling charge structure;3) a free-surface improves the utilizations of explosive energy;4) an air-decoupling charge structure helps to maintain the integrity and stability of wall rock in controlled perimeter blasting, such as in roadways and tunnel excavation by drilling and blasting. 展开更多
关键词 model experiment single borehole cylindrical charge air-decoupling charge structure free surface
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Rolling Control Characteristic Experimental Investigation of a Canard Missile with Free-Spinning Tail 被引量:1
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作者 雷娟棉 吴甲生 孟令涛 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期36-38,共3页
To study the rolling control characteristics of a canard-controlled missile, a series of wind tunnel experiment is conducted. The experimental method, the structure features of wind tunnel model and the experimental r... To study the rolling control characteristics of a canard-controlled missile, a series of wind tunnel experiment is conducted. The experimental method, the structure features of wind tunnel model and the experimental results are introduced in this paper. The experimental data show that the canard is an inefficient rolling control device for canard-controlled missile with fixed tail fins; but for the free-spinning tail fin configuration, the canard can conduct rolling control of the missile, and even have higher controlling efficiency under larger canard deflection angle. 展开更多
关键词 canard missile aerodynamic characteristics wind tunnel experiment free-spinning tail rolling control characteristics
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Effects of hurricane forward speed and approach angle on storm surges: an idealized numerical experiment 被引量:1
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作者 Chenguang Zhang Chunyan Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期48-56,共9页
The effects of hurricane forward speed(V)and approach angle(θ)on storm surge are important and a systematic investigation covering possible and continuous ranges of these parameters has not been done before.Here we p... The effects of hurricane forward speed(V)and approach angle(θ)on storm surge are important and a systematic investigation covering possible and continuous ranges of these parameters has not been done before.Here we present such a study with a numerical experiment using the Finite Volume Community Ocean Model(FVCOM).The hurricane track is simplified as a straight line,such that V andθfully define the motion of the hurricane.The maximum surge is contributed by both free waves and a forced storm surge wave moving with the hurricane.Among the free waves,Kelvin-type waves can only propagate in the down-coast direction.Simulations show that those waves can only have a significant positive storm surge when the hurricane velocity has a down-coast component.The optimal values of V andθthat maximize the storm surge in an idealized semi-circular ocean basin are functions of the bathymetry.For a constant bathymetry,the maximum surge occurs when the hurricane approaches the coast from the normal direction when the free wave generation is minimal;for a stepped bathymetry,the maximum surge occurs at a certain acute approach angle which maximizes the duration of persistent wind forcing;a step-like bathymetry with a sloped shelf is similar to the stepped bathymetry,with the added possibility of landfall resonance when the free and forced waves are moving at about the same velocity.For other cases,the storm surge is smaller,given other parameters(hurricane size,maximum wind speed,etc.)unchanged. 展开更多
关键词 storm SURGE experiments FVCOM HURRICANE forward speed APPROACH ANGLE KELVIN waves forced and free SURGE interactions
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Experimental Simulation of Dolomite Dissolution Under Burial Diagenesis Conditions and Thermodynamic Interpretation 被引量:8
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作者 黄思静 肖林萍 +3 位作者 杨俊杰 张文正 黄月明 刘桂霞 《Chinese Journal Of Geochemistry》 EI CAS 2000年第1期58-64,共7页
Simulating experiments on dolomite dissolution by acetic acid were made under burial diagenesis conditions, at temperatures ranging from 75℃ to 130℃ and pressures from 20 MPa to 30 MPa. The results show that the dis... Simulating experiments on dolomite dissolution by acetic acid were made under burial diagenesis conditions, at temperatures ranging from 75℃ to 130℃ and pressures from 20 MPa to 30 MPa. The results show that the dissolution rate of dolomite increased rapidly with increasing temperature and pressure. From 75℃/20 MPa to 130℃/30 MPa, the total amount of released Ca and Mg increased from 32.98 mg/L to 337.9 mg/L, over one order of magnitude in difference. Thermodynamic calculation indicates that the increment of Gibbs free energy (△G) of the chemical reaction decreases with increasing temperature and pressure. This thermodynamic result is consistent with the experimental result. Based on the experimental results, it is suggested that secondary porosities formed by dolomite dissolution under conditions of deep burial diagenesis should be more common than those under epigenesis and shallow burial conditions, and therefore dolomite reservoirs in the formations that have been deeply buried should be more abundant than in the formations that have only been shallowly buried. 展开更多
关键词 模拟实验 成岩作用 白云石 分解 Gibbs自由能 多孔性
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Experience Free Life in Ancient lown Yangliuqing
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《China & The World Cultural Exchange》 2019年第7期44-46,共3页
Different from the gentle and graceful style of Jiangnan ancient town,Yangliuqing has a more straightforward and heroic character?The architectural style of the town is open and the lines are straight and clear,which ... Different from the gentle and graceful style of Jiangnan ancient town,Yangliuqing has a more straightforward and heroic character?The architectural style of the town is open and the lines are straight and clear,which is especially clean and neat. 展开更多
关键词 experiENCE free LIFE The ARCHITECTURAL STYLE
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Integrated Numerical Experiment of an Intense RF Linac for CIAE Far-Infrared FEL
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作者 Fu Shinian Chen Yinbao Huang Zhibin China Institute of Atomic Energy,P.O.Box 275(17),Beijing 102413 《Chinese journal of nuclear physics》 1997年第2期121-127,共7页
An L band RF linac is now under installation at CIAE to provide intense electronbeam for a far-infrared free-electron laser oscillator.This linac consists of a DC thermionicgun,a subharmonic prebuncher,a buncher,an ac... An L band RF linac is now under installation at CIAE to provide intense electronbeam for a far-infrared free-electron laser oscillator.This linac consists of a DC thermionicgun,a subharmonic prebuncher,a buncher,an accelerating section and a beam transport line.From the INEX(Integrated Numerical Experiment)conducted for prediction of the perfor-mance of the complex and the comparison of some of the simulation results with available ex-perimental data,it shows that the beam quality can satisfy our FEL requirements. 展开更多
关键词 RF LINAC free electron laser INTEGRATED numerical experiments
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Comment on “Analyses of Mössbauer Experiments in a Rotating System: Proper and Improper Approaches” [Annals of Physics Volume 418, July 2020, 168191]
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作者 Jaykov Foukzon 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期416-444,共29页
The notion of classical well localized trajectories of a single photon in Minkowski spacetime does not make any rigorous sense by the well-known existence of a proof that single photons cannot be well localized. This ... The notion of classical well localized trajectories of a single photon in Minkowski spacetime does not make any rigorous sense by the well-known existence of a proof that single photons cannot be well localized. This leads to principal difficultness when photodetection probability on relativistic non inertial frame of reference is considered. In order to resolve this tension, we extend canonical Minkowski geometry up to relevant point-free Minkowski geometry [Ann. Physics 423 (2020) 168329]. The photodetection probability density on uniformly rotating frame endrowed with point-free Lorentzian geometry is obtained. The result of S. A. Podosenov <i>et al</i>. [Ann. Physics 413 (2020) 168047] is obtained without any reference to unphysical notion of the classical trajectories of photon. The paper again shows the correctness of the remarkable result of Prof. C. Corda concerning the Mössbauer rotor experiment as new proof of general relativity, which has been awarded by the Gravity Research Foundation. In addition, the paper also shows various very elementary mistakes, misunderstandings and flaws by the self-called “YARK group”, which is a group of fringe researchers who attempts to promote wrong science, in particular, against the relativity theory. 展开更多
关键词 Mössbauer Rotor experiment Uniformly Rotating Frame Photodetection Probability Density Minkowski Point-free Geometry
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国际自贸区新实践、新规则与我国自贸试验区高质量发展 被引量:1
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作者 廖佳 黄建忠 《国际贸易》 北大核心 2024年第6期45-53,共9页
中国自贸试验区建设已历十载,综合比较国际自贸区发展的理论与实践创新,认真研究和落实国际经贸规则对自贸区建设的相关要求,对推动我国自贸试验区建设高质量发展意义重大。文章首先对国际自贸区研究的学术文献脉络进行了简要梳理,随后... 中国自贸试验区建设已历十载,综合比较国际自贸区发展的理论与实践创新,认真研究和落实国际经贸规则对自贸区建设的相关要求,对推动我国自贸试验区建设高质量发展意义重大。文章首先对国际自贸区研究的学术文献脉络进行了简要梳理,随后总结归纳了国际主要自贸区的最新实践,阐明了国际经贸规则的创新演变。指出当前我国自贸试验区总体上偏重于贸易便利化框架下的制度改革,与投资便利化相关领域的制度创新需要进一步加强,政府采购制度需要进一步深化改革,未来发展战略需要进一步明确等问题。并提出从投资者视角调校自贸试验区建设方向、从可持续发展和新产业技术革命趋势要求出发促进我国自贸试验区(港)高质量发展的思路和政策建议。 展开更多
关键词 自贸试验区 国际经验 国际经贸规则 高质量发展
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自贸区设立何以赋能经济高质量发展——基于贸易、投资与创新的视角 被引量:2
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作者 刘佳 秦芳 《江汉大学学报(社会科学版)》 2024年第1期117-128,共12页
自贸区是国内国际双循环背景下新一轮改革开放的“试验田”,其带来的制度创新与全方位改革对于驱动经济高质量发展具有重要意义。基于2000—2021年省级面板数据,借助自由贸易试验区设立这一准自然实验情景,系统考察自贸区设立对经济高... 自贸区是国内国际双循环背景下新一轮改革开放的“试验田”,其带来的制度创新与全方位改革对于驱动经济高质量发展具有重要意义。基于2000—2021年省级面板数据,借助自由贸易试验区设立这一准自然实验情景,系统考察自贸区设立对经济高质量发展的影响。研究发现:自贸区设立显著促进了经济高质量发展,这一结论经稳健性检验后依旧成立。从作用机制来看,自贸区设立通过贸易效应、投资效应及创新效应三条内在路径影响经济高质量发展。异质性分析发现,自贸区建设引致的经济高质量发展效应在不同设立批次、区位特征省份间存在异质性,且对设立批次早、内陆地区省份产生明显偏好。拓展性分析发现,自贸区建设通过空间溢出效应推动邻近地区经济高质量发展。研究结论在理论上为经济高质量发展新路径探索提供了全新视角,实践上为自贸区持续深化改革创新、推进更高水平对外开放提供了经验证据。 展开更多
关键词 自由贸易试验区 经济高质量发展 准自然实验 双重差分
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易切削钢Te元素含量对其切削表面形貌的影响研究
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作者 雷小宝 庆振华 谢峰 《工具技术》 北大核心 2024年第3期37-42,共6页
采用硬质合金刀具对三种不同Te元素含量的易切削钢12L14,12L14+Te(0.017),12L14+Te(0.05)进行切削实验,研究其已加工表面形貌状态及原因。试验研究结果表明:12L14+Te(0.017)材料的已加工表面最光滑,粗糙度值最小;12L14+Te(0.05)材料的... 采用硬质合金刀具对三种不同Te元素含量的易切削钢12L14,12L14+Te(0.017),12L14+Te(0.05)进行切削实验,研究其已加工表面形貌状态及原因。试验研究结果表明:12L14+Te(0.017)材料的已加工表面最光滑,粗糙度值最小;12L14+Te(0.05)材料的已加工表面最粗糙,微观形貌显示存在较多撕裂;切削不含Te元素的12L14材料时,已加工表面形貌与粗糙度值介于二者之间;添加Te元素材料会生成MnTe等熔点较低的化合物,在切削中起到应力集中源的作用,易导致已加工表面出现微观撕裂现象,但同时减小了刀具积屑瘤形成的可能,所以易切削钢切削表面形貌的生成是二者因素综合影响的结果。 展开更多
关键词 易切削钢 切削试验 表面形貌 粗糙度
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制度型开放对企业投资效率的影响研究——以自由贸易试验区建设为例
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作者 张同功 刘淑琦 陈阳 《青岛科技大学学报(社会科学版)》 2024年第3期18-28,共11页
选取2009—2022年沪深A股上市公司为样本,运用多时点双重差分法检验自贸区建设对企业投资效率的影响。研究表明:自贸区建设能够有效改善企业投资不足和过度投资的情况,进而促进企业投资效率提高;机制检验发现,自贸区建设可以通过创新水... 选取2009—2022年沪深A股上市公司为样本,运用多时点双重差分法检验自贸区建设对企业投资效率的影响。研究表明:自贸区建设能够有效改善企业投资不足和过度投资的情况,进而促进企业投资效率提高;机制检验发现,自贸区建设可以通过创新水平提升效应、税收优惠提高效应、融资环境改善效应和融资约束缓解效应提高企业投资效率;异质性检验发现,自贸区建设能够显著提升民营企业、非资本密集型行业、低层级城市企业的投资效率。基于此,进一步深化制度型对外开放,加强制度型开放政策之间的联动性,因地制宜加强自贸区建设、制定区内政策,对促进企业投资效率提高有重要作用。 展开更多
关键词 自贸区 企业投资效率 准自然实验 多时点双重差分模型
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切削参数对车削12L14钢切削力影响的试验研究
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作者 赵夫超 张增成 +2 位作者 刘畅 杨坤 刘长青 《黑龙江工业学院学报(综合版)》 2024年第2期130-135,共6页
采用硬质合金刀具对12L14易切削钢开展车削正交试验,研究切削深度a p、进给量f和切削速度v c对切削力的影响规律,结果表明:硬质合金刀具在车削12L14易切钢时,对切削力影响最大的因素为切削深度,其次为进给量,而切削速度影响最小。各方... 采用硬质合金刀具对12L14易切削钢开展车削正交试验,研究切削深度a p、进给量f和切削速度v c对切削力的影响规律,结果表明:硬质合金刀具在车削12L14易切钢时,对切削力影响最大的因素为切削深度,其次为进给量,而切削速度影响最小。各方向切削力的变化随着a p、f的增大而线性增大,随着v c的增大有所波动,对切削分力与各切削参数之间的关系进行了多元线性回归分析,建立了切削力经验公式,并利用试验数据验证了经验公式在一定参数阈值下的有效性。 展开更多
关键词 12L14易切削钢 切削试验 切削参数 切削力公式
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空间斯特林热电转换技术在轨试验
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作者 尹钊 张安 +5 位作者 郭佩 闫春杰 赵振昊 张学林 魏志明 陆登柏 《宇航学报》 EI CAS CSCD 北大核心 2024年第1期123-132,共10页
为提高空间同位素电源的效率和功率,满足深空探测、载人登月和火星登陆等航天任务对航天器能源的需求,梳理了空间自由活塞斯特林热电转换涉及的关键技术,设计了天宫空间站空间自由活塞斯特林热电转换装置的在轨试验方案,在轨开展了斯特... 为提高空间同位素电源的效率和功率,满足深空探测、载人登月和火星登陆等航天任务对航天器能源的需求,梳理了空间自由活塞斯特林热电转换涉及的关键技术,设计了天宫空间站空间自由活塞斯特林热电转换装置的在轨试验方案,在轨开展了斯特林热电转换试验,验证了空间微重力环境下双活塞自由运动的间隙密封、双活塞相位保持等关键技术,获取了空间环境下双自由活塞精确的运动相位保持及漂移特性、动力学与热力学强耦合特性等关键参数。在轨试验结果表明,试验装置在轨运行性能良好,热电转换效率达到24.72%,为未来空间高效同位素电源等不依赖太阳能的能源技术应用奠定了基础。 展开更多
关键词 天宫空间站 空间同位素电源 自由活塞 斯特林热电转换 在轨试验
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输电线路单导线自由扭转覆冰动态仿真研究
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作者 杨国林 蒋兴良 +2 位作者 廖乙 胡建林 张志劲 《电工技术学报》 EI CSCD 北大核心 2024年第13期4079-4089,共11页
输电线路冰灾长期威胁电网安全稳定运行,结合输电线路实际覆冰情况,建立准确的输电线路覆冰增长模型对电网冰灾防御具有重要意义。但现有的输电线路覆冰增长模型多忽略了输电线路自由扭转覆冰过程。该文基于野外自然环境下输电线路单导... 输电线路冰灾长期威胁电网安全稳定运行,结合输电线路实际覆冰情况,建立准确的输电线路覆冰增长模型对电网冰灾防御具有重要意义。但现有的输电线路覆冰增长模型多忽略了输电线路自由扭转覆冰过程。该文基于野外自然环境下输电线路单导线自由扭转覆冰的观测结果,建立了反映导线自由扭转覆冰动态过程的仿真分析模型。在重庆大学雪峰山能源装备安全国家野外科学观测研究站开展GJ50导线自由扭转覆冰实验,将实验结果与数值仿真结果进行对比分析。结果表明:导线扭转角度和单位覆冰质量沿单导线中心点对称分布;仿真获得的导线覆冰形状与实际情况吻合;导线扭转角度和单位覆冰质量仿真值与测量值误差平均值均在10%以内。 展开更多
关键词 单导线 扭转覆冰 数值仿真 野外实验验证
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Xe^(23+)离子束轰击低温工况下的无氧铜表面解吸性能研究
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作者 焦纪强 蒙峻 +2 位作者 罗成 柴振 谢文君 《材料导报》 EI CSCD 北大核心 2024年第1期131-135,共5页
强流重离子加速器运行时产生动态真空效应引起束流寿命缩短,需安装无氧铜束流准直器来降低该效应。为探究无氧铜材料在离子束轰击下的解吸性能,本工作设计并研制了满足低温工况的解吸率测试装置,在兰州重离子加速器国家实验室利用Xe^(2... 强流重离子加速器运行时产生动态真空效应引起束流寿命缩短,需安装无氧铜束流准直器来降低该效应。为探究无氧铜材料在离子束轰击下的解吸性能,本工作设计并研制了满足低温工况的解吸率测试装置,在兰州重离子加速器国家实验室利用Xe^(23+)离子束完成了无氧铜温度在4.2 K、20 K、77 K和300 K,以及束流能量为0.58 MeV/u、0.96 MeV/u和1.3 MeV/u的在束试验。结果表明,离子束轰击无氧铜表面时解吸出最多的分子为H_(2),其次分别为H2O、CO、CO_(2)、Ar和O_(2);当温度为4.2 K、束流能量为0.58 MeV/u时无氧铜解吸出H2的比例为87.74%。在同一能量下,随着无氧铜表面温度的升高,解吸率呈增加趋势,能量为0.58 MeV/u时,4.2 K下无氧铜的解吸率仅为25 mol/ion,小于300 K时的600 mol/ion,表明温度越高其解吸产额越大。在同一温度下,随着束流能量的升高无氧铜表面解吸率增加,但增加趋势逐渐减缓,解吸产额趋向饱和。 展开更多
关键词 强流重离子加速器 无氧铜 低温工况 解吸率 在束试验
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本草免洗凝胶的制备及其抗菌作用研究
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作者 朱亮 张珏 +2 位作者 饶洪国 颜德昌 伍明江 《广东化工》 CAS 2024年第10期18-20,共3页
目的:研发本草免洗凝胶,并评估该免洗凝胶抗菌作用。方法:采用正丁醇去除马齿苋色素,将马齿苋药渣与金银花、白及混合后进行提取;以卡波姆-940为基质,按照凝胶剂的制备方法,制成本草免洗凝胶;并对所制备的免洗凝胶进行抗菌作用研究。结... 目的:研发本草免洗凝胶,并评估该免洗凝胶抗菌作用。方法:采用正丁醇去除马齿苋色素,将马齿苋药渣与金银花、白及混合后进行提取;以卡波姆-940为基质,按照凝胶剂的制备方法,制成本草免洗凝胶;并对所制备的免洗凝胶进行抗菌作用研究。结果:本实验研发的75%乙醇-水提取物免洗凝胶色泽均匀、气味清香、手感较好,对大肠杆菌、金黄色葡萄球菌、白色念珠菌、铜绿假单胞菌等具有明显的抑制作用。结论:该本草免洗凝胶制作简单,抗菌作用明显,具有一定的潜在开发应用价值。 展开更多
关键词 本草 提取物 抗菌实验 免洗 凝胶
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塔拉多糖超声提取及其自由基清除能力研究 被引量:3
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作者 徐宜彬 刘运伟 +3 位作者 李阳 董遨宇 惠大勇 李占君 《森林工程》 北大核心 2024年第2期168-175,共8页
为研究塔拉多糖的提取工艺及抗氧化活性,选用超声辅助提取法对塔拉多糖进行提取,围绕液料比、超声功率、提取温度和提取时间展开单因素试验,并通过响应面法对影响参数进行优化。经过统计分析和数学回归模型拟合得知,决定系数(R~2)为0.9... 为研究塔拉多糖的提取工艺及抗氧化活性,选用超声辅助提取法对塔拉多糖进行提取,围绕液料比、超声功率、提取温度和提取时间展开单因素试验,并通过响应面法对影响参数进行优化。经过统计分析和数学回归模型拟合得知,决定系数(R~2)为0.956,即精确系数为95.60%,表明该模型吻合度较好,适用于塔拉多糖超声提取工艺的优化,其最佳参数为10∶1 mL/g, 20 min, 150 W,40℃,实际平均得率为24.58%,接近理论期望得率25.07%。此外,又对塔拉多糖自由基的清除能力进行一阶动力学方面的研究,以维生素C为对照,根据试验数据得知,塔拉多糖的DPPH、ABTS~+对应IC 50分别为524.07和3 496.88μg/mL,说明其在自由基清除能力方面表现较为优异,因此在抗氧化性方面具有较好的应用价值。研究成果最终可为植物多糖的提取、纯化与应用提供可靠的理论指导与数据支撑。 展开更多
关键词 塔拉多糖 超声辅助提取 单因素试验 响应面法 自由基清除能力
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中国(江苏)自由贸易试验区连云港片区的战略提升策略——以海南自由贸易港为借鉴 被引量:1
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作者 张宇霞 宣昌勇 《连云港师范高等专科学校学报》 2024年第1期6-10,共5页
海南自由贸易港在推动建设中国特色自由贸易港的过程中为我国其他自由贸易试验区建设指明了发展方向,提供了经验借鉴。中国(江苏)自由贸易试验区连云港片区经过3年多的建设改革已经进入“深水区”,借鉴海南自由贸易港建设经验对其自身... 海南自由贸易港在推动建设中国特色自由贸易港的过程中为我国其他自由贸易试验区建设指明了发展方向,提供了经验借鉴。中国(江苏)自由贸易试验区连云港片区经过3年多的建设改革已经进入“深水区”,借鉴海南自由贸易港建设经验对其自身建设和发展具有重要意义。中国(江苏)自由贸易试验区连云港片区项目建设存在未完成规划事项、三大功能定位达成度有待进一步提高和溢出效应有待进一步发挥等问题。中国(江苏)自由贸易试验区连云港片区要对标海南自贸港采取以下策略加快战略提升:积极稳妥推进,完成片区建设方案规划的任务;强化三大功能定位,开创对外开放新境界;加速区域融合,释放区域一体化新动力。 展开更多
关键词 自贸区建设 海南自由贸易港 连云港自贸片区 经验借鉴
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