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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： HONG Tao XING GuanYing ZUO huaiyu XUE Song LUO XiaoBing State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump

Application of efficient and sustainable freeze-dissolving technology in manufacturing of KHCO_(3)ultrafine particles

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Green Chemical Engineering 2024年第2期5卷 266-272页

作者： Jiaqi Luo Qifan Su Qiushuo Yu Xinyue Zhai Yuan Zou huaiyu Yang School of Chemical Engineering Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei EnergyInternational Science&Technology Cooperation Base of MOST for Clean Utilization of Hydrocarbon ResourcesNorthwest UniversityXi’an710069China Department of Chemical Engineering Loughborough UniversityLoughboroughLE113TUUnited Kingdom

The development of ultrafine particles provided a new way to solve problems in the fields of energy,environment,and medicine,and had become one of the most promising technologies.Therefore,the application of ultrafine particles required the development of cleaner,greener,and more efficient preparation methods.The new freeze-dissolving technology has been applied in manufacturing of KHCO_(3)ultrafine particles,with an aqueous solution of 0.02-0.1 g KHCO_(3)/g water.Frozen ice particles were formed after dripping the solution into liquid nitrogen.The antisolvent ethanol was used to dissolve the ice spherical template at a temperature below 273.15 K,and the pre-formed KHCO_(3)ultrafine particles inside the ice template remained in the ethanol aqueous solution.The ice particles were put into the freeze dryer to isolate the ultrafine KHCO_(3)particles.Compared with the particles produced with traditional freeze-drying technology,the ultrafine powder/particles produced by the freeze-dissolving technology were smaller with narrower size distribution.The freeze-dissolving technology has demonstrated a much more sustainable and efficient manufacturing process than the traditional freeze-drying process.In addition,the influence of the concentrations of KHCO_(3)and the sizes of ice particles were investigated with the discussions of mechanisms.

关键词： Freeze-dissolving Freeze-drying Ultrafine particles Sustainable

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo huaiyu Li Hongzhi Zhang Lun Pan Chengxiang Shi Kang Xue Xiangwen Zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and utilize.In this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant agarose.The various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were examined.Rheological properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep experiments.The microstructure of the gel was obtained through scanning electron microscopy images.The results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum contents.Notably,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure hydrogel.Additionally,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Illumination and regolith temperature at China's next candidate lunar landing site Shackleton crater

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Science China Earth Sciences 2023年第2期66卷 417-429页

作者： Zhen ZHONG Jianguo YAN huaiyu he Qiling WEN Deyun LIU Jean-Pierre BARRIOT School of Physics and Electronic Science Guizhou Normal UniversityGuiyang550025China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan430079China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing100029China Beijing Spacecraft Manufacturing Co. LtdBeijing100094China Observatory Geodetic de Tahiti BP 657098702Faa’aTahitiFrench Polynesia

This study focuses on the illumination and temperature at China’s next lunar candidate landing site Shackleton crater.We used the NASA’s SPICE system to evaluate the terrain obscuration effect on real-time illumination;the resulting illumination map resembles previous studies,validating the methodologies used in our study.In addition,we estimated an accumulated illumination map for the period of likely rover movement.The map indicates the illuminated inner wall of the Shackleton crater is close to 27%of the whole,meaning that the rover will likely receive solar radiation during its movement.Using the real-time illumination and the distributed 1-D thermal diffusion model,we continuously evaluated the regolith temperature for more than 20 years to stabilize the temperature,and selected the temperature of the end time as the initial value used in a thermal study set for July 20,2023 and May 8,2027.Our results indicate the temperature in the permanent shadow region remains nearly constant,thus validating the stability of our estimated initial temperature.Our results also indicate that the surface temperature is more sensitive to transient illumination,but the subsurface temperature is more likely to be associated with the accumulated illumination.This difference indirectly implies that the conductivity of the lunar regolith is inefficient.The locations receiving more solar radiation show a temperature larger than the threshold(~112 K)of ice stability.The permanently shadowed regions can be as cold as 25 K,and such extreme coldness is a hazard to the rover.There are suitable temperature locations which have a warm surface but cold subsurface to preserve water ice.To further ensure normal rover movement,we provided a map of suitable temperature sites and found that these locations exist not only in the Shackleton crater’s inner wall,but also outside the crater.We suggested four trade-off sampling sites with suitable temperatures and gradual slopes.

关键词： Real-time illumination Regolith temperature Shackleton crater Map of landing site

High-precision geochronology of the Early Cretaceous Yingcheng Formation and its stratigraphic implications for Songliao Basin,China

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Geoscience Frontiers 2022年第4期13卷 89-97页

作者： Tiantian Wang Chengshan Wang Jahandar Ramezani Xiaoqiao Wan Zhiqiang Yu Youfeng Gao huaiyu he Huaichun Wu State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China Institute of Earth Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMA 02139United States Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China College of Earth Sciences Jilin UniversityChangchun 130061China School of Ocean Sciences China University of GeosciencesBeijing 100083China

The Songliao Basin in Northeast Asia is the largest and longest-lived rift basin and preserves a nearcontinuous continental succession of the most of the Cretaceous period,providing great material to investigate the adaption of the terrestrial systems to the Cretaceous greenhouse climate and tectonic events.However,the paucity of precise and accurate radioisotopic ages from the Early Cretaceous strata of the Songliao Basin has greatly held back the temporal and causal correlation of the continental records to the global Early Cretaceous records.Three tuff layers intercalated in the Yingcheng Formation have been intercepted by the SK-2 borehole,which offer excellent materials for radioisotopic dating and calibration of the chronostratigraphy of the Lower Cretaceous sequence of Songliao Basin.Moreover,the Yingcheng Formation recorded the largest and the last of the two major volcanic events in Songliao Basin,which also represents a turning point in the basin evolution history of Songliao from syn-rift stage to post-rift stage.here we report high-precision U–Pb zircon geochronology by the CA-ID-TIMS technique on three tuff samples from the Yingcheng Formation of the SK-2 borehole in the Songliao Basin to construct a greatly improved,absolute age framework for the Yingcheng Formation and provide crucial age constraints for the Songliao Lower Cretaceous Strata.The new CA-ID-TIMS geochronology constrained the Yingcheng Formation at 102.571+0.320/-2.346 Ma to ca.113 Ma,correlating to the Albian Stage.Combined with the previous published Songliao geochronology,the Quantou Formation is constrained to between 96.442+0.475/-0.086 Ma and 91.923+0.475/-0.086 Ma;the Denglouku Formation is constrained to between 102.571+0.320/-2.346 Ma and 96.442+0.475/-0.086 Ma;the age of the Shahezi Formation is estimated at ca.113 Ma to ca.118 Ma,which could extend to ca.125 Ma in some locations in Songliao Basin.The major unconformity between the Yingcheng Formation and the Denglouku Formation,which represents the transition of the basin fr

关键词： U–Pb geochronology Songliao Basin Early Cretaceous Yingcheng Formation China

Nature and evolution of the lithospheric mantle revealed by water contents and he-Ar isotopes of peridotite xenoliths from Changbaishan and Longgang basalts in Northeast China

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Science Bulletin 2019年第18期64卷 1325-1335页

作者： Qinghu Xu Jiaqi Liu huaiyu he Yunhui Zhang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049.China College of Earth Sciences Chinese Academy of SciencesBeijing 100029China Key Laboratory of Earth and Planetary Physics.Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

The nature and evolution of the lithospheric mantle underlying Northeast(NE)China were investigated by assessing the mineral chemistry,water contents,and noble gas(he-Ar)isotopes of peridotite xenoliths captured by Cenozoic basalts from the Changbaishan and Longgang regions.The xenoliths,which have863–1141℃ equilibration temperatures,primarily comprise spinel lherzolites and rare spinel harzburgites.The Mg#(Fo)values of olivine in the peridotite xenoliths vary from 86.9 to 91.3.The clinopyroxenes have high Ti/Eu and low(La/Yb)N,and their chondrite-normalized rare earth elements(REEs)exhibit light REE-depletion to-enrichment patterns,indicating that the mantle underneath the investigated region was predominantly subjected to partial melting(1%–10%)and was metasomatized by silicate melts.The measured3he/4he ratios of the Changbaishan xenoliths have a narrow range from 5.8 Ra to 8.4 Ra with an average of 7.4 Ra.The3he/4he isotopic ratios of the Longgang xenoliths varied from 4.7 Ra to8.1 Ra with an average of 5.9 Ra;slightly lower than the Changbaishan xenoliths.The whole-rock H2Ocontents of the studied peridotite ranged from 9 to 132 ppm.The high H2O contents in excess of50 ppm(up to 132 ppm)might represent newly accreted and cooled asthenospheric materials,while those with H2O contents lower than 50 ppm(as little as 9 ppm)may represent thinned,relic,ancient lithospheric mantle.These geochemical evidences,in combination with published data,indicated that the lithospheric mantle beneath the Changbaishan and Longgang in NE China is dominated by the younger and more fertile lithospheric mantle with a minor ancient and refractory keel.In addition,the lithospheric mantle of this area was metasomatized by melts related to the recent subduction event(e.g.,Pacific oceanic plate).Therefore,the westward-dipping Pacific oceanic plate subduction had an important contribution to the transformation of the lithospheric mantle beneath NE China.

关键词： Subcontinental lithospheric mantle Peridotite xenoliths Mineral chemistry he-Ar isotopes Water contents Northeast China

Impact history and origin of lunar meteorite Northwest Africa 15528

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Science China Earth Sciences 2023年第6期66卷 1399-1422页

作者： Runchuan LIU huaiyu he Thomas SMITH Hanqing YE Huapei WANG Xuhang ZHANG Fei SU Ziheng LIU Wei GUO Peng YANG Chuantong ZHANG Dingshuai Xue Ting CAO Jiannan LI Xuelong JIANG Ye he Chao LU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institutes of Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Paleomagnetism and Planetary Magnetism Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Institution of Meteorites and Planetary Materials Research Center Guilin University of TechnologyGuilin 541004China

No samples from the Moon’s far side have been returned to Earth.Thus,lunar meteorite study can deepen the understanding of the Moon’s far side(if we can identify which lunar meteorites came from the Moon’s far side).The Northwest Africa(NWA)15528 meteorite is a lunar feldspathic regolith breccia meteorite and we speculated it might originate from the Feldspathic Highlands Terrane(FHT)on the far side of the Moon.here,we report detailed petrography,major and trace elements,and noble gas(he,Ne,and Ar)isotopes for the clasts and matrix,respectively.The results show that the NWA 15528 lunar meteorite contains diverse clasts,including anorthosite,granulite,basalt,and impact melt clasts.The coarse,wellcrystallized,uniform chemical composition minerals may come from intrusive plutonic rocks.Among the anorthosite clasts,the norite/olivine clasts originate from the deep lunar crust,whereas the other anorthosite clasts are from lunar highlands.The Sm concentrations in NWA 15528 were similar to those in the fourth group of Apollo 16 melt samples,demonstrating that NWA 15528 has a typical plagioclase highland meteorite composition.Compared with the Apollo sample data and remote sensing results,the chemical composition of NWA 15528 indicated strong affinities with the FHT area and ferroan anorthosite(FAN)material from the far side of the Moon.The noble gas isotopic composition of NWA 15528 is consistent with a binary mixture of solar wind and cosmogenic components;during stepwise pyrolytic extractions,we observed that the abundance of cosmogenic components decreased,whereas that of solar wind components increased with increasing temperature.The average cosmic-ray exposure(CRE)age of the matrix and granulite is 42±6 Ma,with a shielding depth in the same range of 10-20 g cm^(−2).The gas retention age of NWA 15528 is 2.14 Ga,and the antiquity age of NWA 15528 is(0.69-0.74)±0.2 Ga(considering 50%40Arm is 40Artrap)which indicates the different clasts of NWA 15528 are assembled after 0.69-0.74 Ga.

关键词： The Moon Regolith Meteorites Cosmic rays Solar wind Thermal histories Far side of the Moon

Structural insight into the dual-antagonistic mechanism of AB928 on adenosine A_(2)receptors

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Science China(Life Sciences) 2024年第5期67卷 986-995页

作者： Yuan Weng Xinyu Yang Qiansen Zhang Ying Chen Yueming Xu Chenyu Zhu Qiong Xie Yonghui Wang huaiyu Yang Mingyao Liu Weiqiang Lu Gaojie Song Shanghai Key Laboratory of Regulatory Biology Institute of Biomedical Sciences and School of Life SciencesEast China Normal UniversityShanghai 200241China Department of Medicinal Chemistry School of PharmacyFudan UniversityShanghai 201203China

The adenosine subfamily G protein-coupled receptors A_(2A)R and A_(2B)R have been identified as promising cancer immunotherapy candidates.One of the A_(2A)R/A_(2B)R dual antagonists,AB928,has progressed to a phaseⅡclinical trial to treat rectal cancer.However,the precise mechanism underlying its dual-antagonistic properties remains elusive.herein,we report crystal structures of the A_(2A)R complexed with AB928 and a selective A_(2A)R antagonist 2-118.The structures revealed a common binding mode on A_(2A)R,wherein the ligands established extensive interactions with residues from the orthosteric and secondary pockets.In contrast,the cAMP assay and A_(2A)R and A_(2B)R molecular dynamics simulations indicated that the ligands adopted distinct binding modes on A_(2B)R.Detailed analysis of their chemical structures suggested that AB928 readily adapted to the A_(2B)R pocket,while 2-118 did not due to intrinsic differences.This disparity potentially accounted for the difference in inhibitory efficacy between A_(2B)R and A_(2A)R.This study serves as a valuable structural template for the future development of selective or dual inhibitors targeting A_(2A)R/A_(2B)R for cancer therapy.

关键词： adenosine receptor A2AR A2BR inhibitor dual-antagonism drug discovery

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国产“年代剧”的叙事新变与价值引领

艺术传播研究 2024年第2期 128-134页

作者：肖怀宇中国传媒大学

近年来,国产“年代剧”佳作频现,《人世间》等作品已“破圈”传播。从时代精神的真实再现、文化记忆的创新重构、家国情怀的伦理内涵、温暖现实的价值导向等几个方面入手,可分析这些“年代剧”广受欢迎的原因,并从其间总结出优秀国产“... 详细信息

近年来,国产“年代剧”佳作频现,《人世间》等作品已“破圈”传播。从时代精神的真实再现、文化记忆的创新重构、家国情怀的伦理内涵、温暖现实的价值导向等几个方面入手,可分析这些“年代剧”广受欢迎的原因,并从其间总结出优秀国产“年代剧”在叙事上的新策略、新特点。

关键词：年代剧影视叙事时代精神文化记忆家国情怀温暖现实主义

波前编码红外成像系统的温度梯度适应能力探究

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天津大学学报（自然科学与工程技术版） 2024年第5期57卷 521-529页

作者：盛婧蔡怀宇汪毅陈晓冬天津大学精密仪器与光电子工程学院天津300072

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯... 详细信息

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯度模型来仿真非稳态下的温度变化.利用温度梯度模型来定性分析光学系统在轴向、径向温度梯度为系统引入的附加像差.计算两个方向下的光程差变化来比较两种温度梯度环境下系统的成像性能差异.在此基础上,为非稳态温度环境下红外光学系统的设计建立了结合光/机/热分析的无热化设计流程,通过ZEMAX设计了一套最大轴向尺寸为85 mm、最大径向尺寸为25 mm的红外光学系统,通过SolidWorks加载轴向和径向的热形变,探究所设计的系统能够适用的温度梯度范围.结果表明,结合光/机/热分析的无热化设计流程可以有效表明系统在非稳态温度下的成像情况.对上述采用三次相位板进行无热化设计的红外光学系统,在非稳态温度下可以适应±10℃的轴向温差范围,但是仅可以适应±1℃的径向温差范围.因此在进行红外波前编码光学系统的无热化设计时,需要对径向方向进行重点优化.

关键词：波前编码技术红外光学成像系统温度梯度三次相位板