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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

Characteristics and demographic factors of traditional Chinese medicine constitution types among elderly individuals in China:A national multistage cluster random study Author links open overlay panel

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Journal of Traditional Chinese Medical Sciences 2024年第3期11卷 257-263页

作者： Jing Xia Minghua Bai Huirong song Houqin Li Dayan Zhang Mary y.Jiang Ran Chen Feiyu He Cheng Ni Center for Studies in Constitution and Reproductive Sciences of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China National Institute of TCM Constitution and Preventive Medicine Beijing University of Chinese MedicineBeijing 100029China Huangsi Comprehensive Outpatient Department Beijing Tongrentang Healthcare Industry Investment Group CompanyBeijing 100032China Zhangjiakou Second Traditional Chinese Medicine Hospital Zhangjiakou 076250China Faculty of Medicine The Chinese University of Hong KongHong Kong 999077China

Objective To reveal the distribution characteristics and demographic factors of traditional Chinese medicine(TCM)constitution among elderly individuals in *** Elderly individuals from seven regions in China were selected as samples in this study using a multistage cluster random sampling *** basic information questionnaire and Constitution in Chinese Medicine Questionnaire(Elderly Edition)were *** statistical analysis,chi-squared tests,and binary logistic regression analysis were *** The single balanced constitution(BC)accounted for 23.9%.The results of the major TCM constitution types showed that BC(43.2%)accounted for the largest proportion and unbalanced constitutions ranged from 0.9%to 15.7%.East China region(odds ratio[OR]=2.097;95%confidence interval[CI],1.912 to 2.301),married status(OR=1.341;95%CI,1.235 to 1.457),and managers(OR=1.254;95%CI,1.044 to 1.505)were significantly associated with ***>70 years was associated with qi-deficiency constitution and blood stasis constitution(BSC).Female sex was significantly associated with yang-deficiency constitution(OR=1.646;95%CI,1.52 to 1.782).Southwest region was significantly associated with phlegm-dampness constitution(OR=1.809;95%CI,1.569 to 2.086).North China region was significantly associated with inherited special constitution(OR=2.521;95%CI,1.569 to 4.05).South China region(OR=2.741;95%CI,1.997 to 1.3.763),Central China region(OR=8.889;95%CI,6.676 to 11.835),senior middle school education(OR=2.442;95%CI,1.932 to 3.088),and managers(OR=1.804;95%CI,1.21 to 2.69)were significantly associated with *** This study defined the distribution characteristics and demographic factors of TCM constitution in the elderly *** and improving unbalanced constitutions,which are correlated with diseases,can help promote healthy aging through the scientific management of these demographic factors.

关键词： Constitution in Chinese Medicine Questionnaire(Elderly Edition) Body constitution Multistage cluster random sampling Demographic factors Elderly individuals

Seedling dynamics differ between canopy species and understory species in a tropical seasonal rainforest,SW China

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Plant Diversity 2024年第5期46卷 671-677页

作者： Libing Pan Xiaoyang song Wenfu Zhang Jie yang Min Cao CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

We used 11 years of census data from 450 seedling quadrats established in a 20-ha forest dynamics plot to study seedling dynamics in tree species of a tropical seasonal rainforest in Xishuangbanna,southwestern *** found that overall seedling recruitment rate and relative growth rate were higher in the rainy season than in the dry *** the recruitment rate of seedlings from canopy tree species(two species)and the relative growth rate of seedlings from understory species(nine species)were higher in the rainy season than in the dry ***,in the rainy season,the recruitment rate of seedlings was higher for canopy tree species than for understory tree *** addition,relative growth rate of seedlings was higher in the canopy species than in understory seedlings in the dry *** also observed that,in both rainy and dry seasons,mortality rate of seedlings was higher for canopy species than for understory ***,canopy tree species appear to have evolved a flexible strategy to adapt to the seasonal changes of a monsoon *** contrast,understory tree species seem to have adopted a conservative ***,these species mainly release seedlings in the rainy season and maintain relatively stable populations with a lower mortality rate and recruitment rate in both dry and rainy *** study suggests that canopy and understory seedling populations growing in forest understory may respond to future climate change scenarios with distinct regeneration strategies.

关键词： Tropical forest Tree seedling Seasonality Recruitment Mortality Relative growth rate

Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries

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Nano-Micro Letters 2024年第8期16卷 268-308页

作者： yiding Li Li Wang youzhi song Wenwei Wang Cheng Lin Xiangming He Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084People’s Republic of China National Engineering Research Center of Electric Vehicles Beijing Institute of Technology(BIT)Beijing 100081People’s Republic of China Shenzhen Automotive Research Institute of BIT(Shenzhen Research Institute of National Engineering Research Center of Electric Vehicles) Shenzhen 518118People’s Republic of China

The battery technology progress has been a contradictory process in which performance improvement and hidden risks *** the battery is still a“black box”,thus requiring a deep understanding of its internal *** battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing *** paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety *** paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”*** the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed *** advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system ***,with the help of smart batteries in the future,the importance of consistency can be weakened or even *** application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life.

关键词： Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic

Trial characteristics and treatment effect estimates in randomized controlled trials of Chinese herbal medicine: A meta-epidemiological study

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Journal of Integrative Medicine 2024年第3期22卷 223-234页

作者： Betty H.Wang ya-li Lin yin-yan Gao Jin-lu song Lang Qin Ling-qi Li Wen-qi Liu Claire C.W.Zhong Mary y.Jiang Chen Mao Xiao-bo yang Vincent C.H.Chung Irene X.y.Wu Jockey Club School of Public Health and Primary Care the Chinese University of Hong KongHong Kong 999077China Xiangya School of Public Health Central South UniversityChangsha 410006Hunan ProvinceChina School of Chinese Medicine the Chinese University of Hong KongHong Kong 999077China School of Public Health Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina State Key Laboratory of Dampness Syndrome of Chinese Medicine the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Chinese Medicine Syndrome Research Team the Second Affiliated HospitalGuangzhou University of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome Guangzhou 510120Guangdong ProvinceChina Hunan Provincial Key Laboratory of Clinical Epidemiology Central South UniversityChangsha 410006Hunan ProvinceChina

Background:Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials(RCTs).Nevertheless,it remains unclear if similar associations exist in RCTs on Chinese herbal medicine(CHM).Further,Chinese medicine-related characteristics have not been explored ***:To investigate trial characteristics related to treatment effect estimates on CHM *** strategy:This meta-epidemiological study searched 5 databases for systematic reviews on CHM treatment published between January 2011 and July *** criteria:An eligible systematic review should only include RCTs of CHM and conduct at least one *** extraction and analysis:Two reviewers independently conducted data extraction on general characteristics of systematic reviews,meta-analyses and included *** also assessed the risk of bias of RCTs using the Cochrane risk of bias tool.A two-step approach was used for data *** ratio of odds ratios(ROR) and difference in standardized mean differences (dSMD) with 95%confidence interval (CI) were applied to present the difference in effect estimates for binary and continuous outcomes,***:Ninety-one systematic reviews,comprising 1338 RCTs were *** binary outcomes,RCTs incorporated with syndrome differentiation (ROR:1.23;95%CI:[1.07,1.39]),adopting Chinese medicine formula (ROR:1.19;95%CI:[1.03,1.34]),with low risk of bias on incomplete outcome data (ROR:1.29;95%CI:[1.06,1.52]) and selective outcome reporting (ROR:1.12;95%CI:[1.01,1.24]),as well as a trial size≥100 (ROR:1.23;95%CI:[1.04,1.42]) preferred to show larger effect *** for continuous outcomes,RCTs with Chinese medicine diagnostic criteria (dSMD:0.23;95%CI:[0.06,0.41]),judged as high/unclear risk of bias on allocation concealment (dSMD:-0.70;95%CI:[-0.99,-0.42]),with low risk of bias on incomplete outcome data (dSMD:0.30

关键词： Chinese herbal medicine Randomized controlled trial Risk of bias Meta-epidemiological study Effect estimates

Molecular design of recyclable thermosetting polyimide and its composite with excellent mechanical and tribological properties

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Friction 2024年第3期12卷 452-461页

作者： Xiaoyue WANG Zenghui yANG Tingmei WANG Qihua WANG Xinrui ZHANG song LI Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Recyclability of thermosetting polymers and their composites is a challenge for alleviating environmental pollution and resource *** this study,solvent-recyclable thermosetting polyimide(PI)and its composite were successfully *** tensile strength,elongation at break,and young’s modulus of PI are 108.70±7.29 MPa,19.35%±3.89%,and 2336.42±128.00 MPa,*** addition of reduced graphene oxide(RGO)not only enhances the mechanical properties of PI but also endows it with excellent tribological *** PI illustrates a high recycling efficiency of 94.15%,but the recycled composite exhibits inferior mechanical *** recycling and utilization of PI and its composite are realized through imine bonds(-C=N),which provides new guidance for solving the problem of environmental pollution and resource waste and is potential application in the field of sustainable tribology.

关键词： thermosetting polyimide(PI) recyclability dynamic covalent bonds friction and wear polymer composites

Crystallization of RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of layered hydroxides(RE=Gd-Lu lanthanides and y),derivation of RE_(2)O_(2)SO_(4),photoluminescence and optical thermometry

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Journal of Rare Earths 2024年第8期42卷 1496-1506,I0003页

作者： Fan Li Zhenqi song Zhiyuan Pan Sihan Feng Qi Zhu Ji-Guang Li Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Functional Materials National Institute for Materials ScienceTSsukuboaIbaraki3050044Japan

Layered rare-earth hydroxides(LREHs) draw wide research interest because of their peculiar crystal structure,rich interlayer chemistry and abundant functionality of the RE element,but are limited to the two categories of RE_(2)(OH)_(5)A·nH_(2)O(A:typical of Cl^(-)or NO_(3)^(-)) and RE_(2)(OH)_(4)SO_(4)·nH_(2)*** the other hand,rare-earth oxysulfates(RE_(2)O_(2)SO_(4)) have attracted attention due to their properties of large-capacity oxygen storage,low-temperature magnetism and luminescence,but their preparation procedure mostly involves toxic SO_(x) gases and/or complicated *** this work,RE_(2)(OH)_(2)CO_(3)SO_(4)·nH_(2)O as a new family of LREHs(RE=Gd-Lu lanthanides and y) were produced via hydrothermal reaction,from which phase-pure RE_(2)O_(2)SO_(4) was derived via subsequent annealing at 800℃ in air without the involvement of SO_(x),The compounds were thoroughly characterized to reveal the intrinsic influence of lanthanide contraction(RE^(3+) radius) on crystal structure,thermal behavior(dehydroxylation/decarbonation/desulfurization),vibrational property and crystallite *** analyzing the photoluminescence of Eu^(3+) and Sm^(3+)in the Gd_(2)O_(2)SO_(4) typical host it is found that the 617 nm(Eu^(3+),λ_(ex)=275 nm) and 608 nm(Sm^(3+),λ_(ex)=407 nm) main emissions can retain as high as ^(7)9.6% and 85.5%of their room-temperature intensities at 423 K,with activation energies of ~0.19 and 0.21 eV for thermal quenching,*** also indicates that both the phosphors have the potential for optical temperature sensing via the fluorescence intensity ratio(FIR) technology,whose maximum relative sensitivity reaches -2.70%/K for Eu^(3+)and 1.73%/K for Sm^(3+) at 298 K.

关键词： Layered hydroxide RE_(2)O_(2)SO_(4) Luminescence Optical temperature sensing Rare earths

Preparation and combustion properties of laminated sticks of B-CuO and B-Bi_(2)O_(3)

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Defence Technology（防务技术） 2024年第8期38卷 67-74页

作者： Haoyu song Chenyang Li Fubing Gao Chongwei An Shijiao Li Xuan Zhan Jianchen He School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Chongqing Military Agency of the Army Chongqing 400060China

To explore the composite process of B-CuO and B-Bi_(2)O_(3) two-component laminated sticks,obtain the corresponding sticks with good printing effect,and explore the energy release *** this study,boron,copper oxide,and bismuth trioxide powders were dispersed in the dispersed phase (DMF) using F_(2602) as a binder,and the construction of two-component B-CuO,B-Bi_(2)O_(3),three-component microcomposite,and three-component macro-composite sticks were realized with the help of double nozzle direct ink writing (DIW) technique *** resulting sticks were ignited by a nichrome wire energized with a direct current,and a high-speed camera system was used to record the combustion behavior of the sticks,mark the flame position,and calculate the rate of *** results showed that the B-CuO stick burning rate (42.11 mm·s^(-1)) was much higher than that of B-Bi_(2)O_(3)(17.84 mm·s^(-1)).The formulation with the highest CuO content (ω_(CuO)=58.7%) in the microscale composite of the sticks also had the fastest burning rate of 60.59 mm·s^(-1),as the CuO content decreased (ω_(CuO)=43.5%,29.3%),its burning rate decreased to 34.78 mm·s^(-1),37.97 mm·s^(-1).The stick with the highest copper oxide content(ω_(CuO)=60%) also possessed the highest burning rate (48.84 mm·s^(-1)) in the macro-composite sticks,and the burning rates of the macro-composite sticks with component spacing of 0.1 mm,0.2 mm,and 0.5 mm were 43.34 mm·s^(-1),48.84 mm·s^(-1),and 40.76 mm·s^(-1).

关键词： Boron-based thermite Direct ink writing Linear burning rate Multi-component composite

Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using y_(2)O_(3) additive

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Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi yu yi-hong Shi Ping Liu yong-wan Wu Cheng-hao song Xian-gong Deng Xiang Ding song-lin Ran yi Zhang Hai-jun Zhang Hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and y_(2)O_(3) as an *** effects of y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide y_(2)O_(3) Mechanical property Heat conductivity

Synergistic extraction of rare earth elements and alumina from coal fly ash by potassium pyrosulfate

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Journal of Rare Earths 2024年第4期42卷 749-758页

作者： Jingjing Zou yiping Sun Chunbin Guo Daye Chen yonghong song yongfeng Wu Zhaotianhui Li Department of Environment Science and Engineering Liaoning Technical UniversityFuxin23000China Department of Materials Science and Engineering Liaoning Technical UniversityFuxin123000 China Technology Research and Development Department Chinese Institute of Coal ScienceBeijing100013China Shenhua Zhungeer Energy and Resource Comprehensive Development Co. Ltd.Erdos10300China Liaoning yingguan High-tech Ceramic Co. Ltd.Jinzhou121213China

Although coal fly ash(CFA)contains a high content of rare earth elements(REEs),the related extraction methods have limitations because of their low efficiencies,high levels of energy consumption,and other *** address these problems,in this study,we examined the coextraction of REEs and Al_(2)O_(3)from two types of Al_(2)O_(3)-rich CFA,pulverized CFA(PCFA)and circulating fluidized bed fly ash(CFBFA)using low-temperature calcination in the presence of K_(2)S_(2)O_(7).The total REEs,heavy REEs(HREEs),and light REEs(LREEs)extraction efficiencies were determined using different K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios and calcination temperatures and correlated with the Al_(2)O_(3) extraction efficiency using Pearson correlation coefficient *** REEs are concentrated within CFA particles encapsulated in an aluminosilicate glass phase,and the REEs extraction efficiency is related to the form of Al in *** extraction efficiencies of Al_(2)O_(3) and REEs increase as the K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratio and calcination temperature increase,and the extraction selectivity of the more industrially valuable HREEs from CFBFA is *** high K_(2)S_(2)O_(7)/Al_(2)O_(3) molar ratios,the extraction of REEs from PCFA is more efficient than that from CFBFA with the regeneration of the highly active Al-O-Si bonds in *** Al_(2)O_(3) extraction efficiencies of PCFA as well as CFBFA correlate strongly with the total REEs,HREEs,and LREEs extraction *** developed extraction technology has the potential to promote CFA valorization and expand REEs resources,thus mitigating the bottlenecks of REEs procurement.

关键词： Rare earths Alumina Coal fly ash Potassium pyrosulfate Calcination Extraction