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“吉林省通过海参崴内贸中转”背景下的东北铁路货运发展策略

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物流技术 2024年第2期43卷 20-26页

作者：张云逸刘文歌石可周可大连交通大学经济管理学院辽宁大连116028

在扩大吉林省内贸跨境运输范围、利用海参崴进行内贸跨境中转的背景下,如何促进铁路货运高质量发展意义重大。在系统梳理东北地区内贸跨境运输发展沿革的基础上,分析了通过海参崴跨境中转对我国东北地区固有铁路货源的影响,得出吉林省... 详细信息

在扩大吉林省内贸跨境运输范围、利用海参崴进行内贸跨境中转的背景下,如何促进铁路货运高质量发展意义重大。在系统梳理东北地区内贸跨境运输发展沿革的基础上,分析了通过海参崴跨境中转对我国东北地区固有铁路货源的影响,得出吉林省至上海局管内铁路货源、吉林省至辽宁省铁路集港货源、吉林省至南方各局管内铁路货源可能受到影响的初步研判。接着从作业能力和运输组织两个方面分析了吉林通过海参崴内贸中转的制约因素,如:铁路换装作业效率低下、铁路口岸的作业能力差、货源组织模式较为落后等。基于以上问题,提出应完善铁路运营条件、缩短换装作业时间、提高港口作业效率等,持续增强铁路货运作业能力;积极对接市场、开行海铁联运班列、与船公司合作等,不断优化铁路货物运输组织模式;依托吉林省内铁路货场打造海铁、公铁多式联运综合性枢纽;多方协同改进货物装载运输方案,优化运输设备设计,提高运输技术水平等策略,以期为东北铁路货运的高质量发展提供参考。

关键词：铁路货运内贸跨境运输东北地区海参崴

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大苞藤黄叶化学成分研究

中草药 2024年第3期55卷 697-704页

作者：梅贵陆正阳谷英姿石可熊慧陈玉杨光忠中南民族大学药学院湖北武汉430074 中南民族大学化学与材料科学学院湖北武汉430074 国家中医药管理局民族药学三级实验室湖北武汉430074

目的研究大苞藤黄Garcinia bracteata叶化学成分。方法采用正、反相硅胶柱色谱及高效液相色谱等多种技术进行分离纯化,并通过NMR、HR-ESI-MS以及量子化学计算鉴定化合物结构。通过CCK-8方法,评价了所有化合物对人非小细胞肺癌细胞A54... 详细信息

目的研究大苞藤黄Garcinia bracteata叶化学成分。方法采用正、反相硅胶柱色谱及高效液相色谱等多种技术进行分离纯化,并通过NMR、HR-ESI-MS以及量子化学计算鉴定化合物结构。通过CCK-8方法,评价了所有化合物对人非小细胞肺癌细胞A549体外抗增殖活性。结果从大苞藤黄叶醋酸乙酯提取物中分离得到了12个化合物,分别鉴定为1,3,5-三羟基-5,6,7,8-四氢[口山]酮(1)、1,3-二羟基-5-羰基-5,6,7,8-四氢[口山]酮(2)、1,3,5,6-四羟基-8-异戊烯基缩酚酸环醚(3)、松脂醇(4)、对羟基苯丙烯酸(5)、3-甲氧基-4,4’,5-三羟基联苯(6)、(2S)-2,9-巨豆二羟基-6-烯-1-酮(7)、(2R)-2,9-巨豆二羟基-6-烯-1-酮(8)、(5Z)-9-羟基-1,5-巨豆二烯-2-酮(9)、2-氧代-α-紫罗兰醇(10)、黑麦草内酯(11)、gardeterpenoneA (12)。结论化合物1、2为新的[口山]酮类化合物,化合物3为新的缩酚酸类化合物,分别命名为大苞藤黄甲素、大苞藤黄乙素和大苞藤黄丙素(garbractinones A-C);化合物7~10为降倍半萜类化合物,化合物11、12为单萜类化合物,均是首次从大苞藤黄叶中分离得到。所有化合物(50μmol/L)对A549细胞没有表现明显的抗增殖活性,其抑制率小于50%。

关键词：藤黄属大苞藤黄叶 [口山]酮缩酚酸环醚降倍半萜大苞藤黄甲素大苞藤黄乙素大苞藤黄丙素

数字金融促进经济高质量发展效应与机制研究——基于双创驱动视角

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经济问题 2024年第3期 69-75页

作者：张高明边亚静石可敬冯琛琛首都经济贸易大学金融学院北京100070 河北经贸大学金融学院河北石家庄050051 河北省城乡融合发展协同创新中心河北石家庄050051 广西师范大学经济管理学院广西桂林541004

在选取2011—2021年面板数据,并基于主成分分析法测度了各省级行政区经济高质量发展指数后,从双创视角研究了数字金融助推经济高质量发展的效果和机制。研究发现,数字金融对经济高质量发展有明显的推动效应,且双创驱动发挥着重要的机制... 详细信息

在选取2011—2021年面板数据,并基于主成分分析法测度了各省级行政区经济高质量发展指数后,从双创视角研究了数字金融助推经济高质量发展的效果和机制。研究发现,数字金融对经济高质量发展有明显的推动效应,且双创驱动发挥着重要的机制作用;异质性检验结果表明,地区与政府干预程度不同,数字金融的作用效果会有所区别;数字金融与经济高质量发展存在门槛效应,且双创因素能够动态强化推动经济高质量发展的效果。

关键词：数字金融经济高质量发展技术创新创业活跃度

Analysis of the dominant frequency in a subsonic compressor stator at near stall condition

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Chinese Science Bulletin 2014年第1期59卷 23-28页

作者： ke shi Song Fu School of Aerospace Tsinghua University

IDDES method was applied to investigate the highly unsteady flow in a subsonic compressor stator with very large hub clearance and high incidence *** blade loading variation frequency was found close to the rotating instability(RI)frequency f RI&333 Hz observed in the *** analysis of the flow physics shows that the loading variation is caused by the periodic swing of the large scale separated flow on the blade suction side *** breakdown of the leakage vortex has no significant dominant frequencies,thus cannot be the cause of RI in this compressor stator as normally ***,the vortex shedding and vortex breakdown due to shear layer instability at the outer edge of the blade suction surface separation region excite high frequency unsteadiness that can form the sources of noise.

关键词：压气机亚音速静子非定常流动频分状态失速优势频率

Empirical Research on the Application of a Structure-Based Software Reliability Model

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IEEE/CAA Journal of Automatica Sinica 2021年第6期8卷 1153-1162页

作者： Jie Zhang Yang Lu ke shi Chong Xu School of Computer and Information Anhui Normal UniversityWuhu 241003China School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230601China

Reliability engineering implemented early in the development process has a significant impact on improving software *** can assist in the design of architecture and guide later testing,which is beyond the scope of traditional reliability analysis *** reliability models work for this,but most of them remain tested in only simulation case studies due to lack of actual *** we use software metrics for reliability modeling which are collected from source codes of post *** the proposed strategy,redundant metric elements are filtered out and the rest are aggregated to represent the module *** further propose a framework to automatically apply the module value and calculate overall reliability by introducing formal *** experimental results from an actual project show that reliability analysis at the design and development stage can be close to the validity of analysis at the test stage through reasonable application of metric *** study also demonstrates that the proposed methods have good applicability.

关键词： Algebraic method reliability evaluation software metrics software reliability

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浮球覆盖下水面能量平衡再建与蒸发模型研究

长江科学院院报 2024年第3期41卷 22-29页

作者：徐思远严新军王海涛侍克斌新疆农业大学水利与土木工程学院乌鲁木齐830052 新疆水利工程安全与水灾害防治重点实验室乌鲁木齐830052

针对干旱区平原水库蒸发强烈导致水资源利用率低的问题,选用黑色高密度聚乙烯(HDPE)浮球作为干旱区平原水库节水材料。通过理论分析、建模与室外试验三者结合,对完整非冰冻期内浮球覆盖下水面蒸发、水体能量平衡组分变化分布的响应机理... 详细信息

针对干旱区平原水库蒸发强烈导致水资源利用率低的问题,选用黑色高密度聚乙烯(HDPE)浮球作为干旱区平原水库节水材料。通过理论分析、建模与室外试验三者结合,对完整非冰冻期内浮球覆盖下水面蒸发、水体能量平衡组分变化分布的响应机理进行研究,并在此基础上建立相应的水面蒸发量计算模型。结果显示:相较于自由水面,73%的浮球覆盖率下的整体水面净辐射吸收率减小约12.6%,其月均蒸发所需潜热通量减少了61.8%,约为148.73 W/m^(2),水体的感热通量和蓄热通量也有较大的变化。通过对彭曼模型的能量项和空气动力项进行修正,建立的覆盖条件下的水面蒸发量计算模型具有较高的精度。

关键词：浮球节水材料能量平衡蒸发模型水资源利用率

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Controlled Growth Morphology of Porous Nanocrystal Iron Oxide by Electrodeposition

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Chemical Research in Chinese Universities 2009年第5期25卷 595-599页

作者： LI Li shi ke-ying key Laboratory of Functional Inorganic Material Chemistry Ministry of Education Laboratory of Physical Chemistry School of Chemistry and Materials Science Heilongjiang University Harbin 150080 P. R. China

Fe（Ⅱ） was deposited into the bottom of the mesopores of highly ordered large caged cubic mesoporous silica by electrodeposition. And the deposited Fe mesoporous silica thin film was treated by 1%---4% HF to remove the SiO2 template and then calcined. It was found that nanowire bundles, dendritic plates of porous iron oxide, dense parallel backbones of porous iron oxide were obtained at -1.4-- -1.6 V and 0.08--0.1 mol/L electrolyte concentration after calcinations; the dendritic pattern of porous iron oxide film templated by the SBA-16 film was obtained in macrostructure at a higher absolute value of cathode potential（-1.7-- -1.8 V） and a lower electrolyte concentration（0.02-0.05 mol/L）, the dendritic pattern of porous iron oxide film could copy the microstructure of SBA-16 film; Fe（II） nanowires grew and formed in one dimension（1D） and two-dimension（2D） electrocrystallization at a potential of-l.6-- -1.7 V and an electrolyte concentration of 0.05 mol/L, and the shape of the ID or 2D crystalline iron oxide nanowires calcined was similar to the original shape of the SBA-16 channels. The desired morphology and size of porous nanocrystal iron oxide can be obtained by adjusting the applied potential value and electrolyte concentration, and all kinds of morphologies of porous nanostructure crystal iron oxide can be prepared.

关键词： Electrocrystallization Deposition Porous iron oxide Morohology

Effects of Austenizing Temperature on Reprecipitation of BN

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Journal of Iron and Steel Research International 2013年第9期20卷 99-104页

作者： YIN shi-ke A Rong Mitsuru Tanino China Iron and Steel Research Institute Group Fundamental Research Laboratory Nippon Steel Co.

Most of BN was precipitated around the spherical MnS and formed the compound of MnS and BN during the isothermal treatment at 850 ℃ after austenizing at 950-1050 ℃. Most of MnS was transformed into polygon when austenized at 1 150 ℃ or above, which could not be the nuclei of BN anymore. During the insulation process at 850 ℃, MnS kept the state of monomer. The compound of MnS and BN at earlier time was of fine polycrystalline in spherality and BN was formed as a plate-like monocrystal on a certain part of the polycrystalline when its dimension reached 0.6 μm.

关键词： austenizing temperature BN repreeipitation isothermal treatment

Numerical investigation of the casing treatment mechanism with a single circumferential groove

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Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 353-365页

作者： shi ke CHEN HaiXin FU Song School of Aerospace Tsinghua University

The paper investigates the effect of a single circumferential groove casing treatment(CGCT) on a transonic compressor rotor *** particular,the effect of the groove at different axial locations on the flow field is studied in detail and stall margin improvement is also *** present results show that the groove close to the leading edge plays a crucial role in stabilizing the near stall flow structures and,hence,improves the stall *** groove at the mid-chord-section of the blade can help exchange and transfer momentums between different directions,and suppress the flow unsteadiness,leading to increased efficiency in rotor performance and extended operation *** groove located near the blade trailing edge has limited effects on stall margin improvement and may cause additional penalty in *** comparison with the recent work on CGCT,some common flow physics can be observed.

关键词： compressor casing treatment circumferential groove transonic rotor stall margin