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Guidance, Navigation and Control 2024年第1期4卷 86-101页

作者： Bin Zhou kang-kang Zhang Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 P.R.China Department of Mechanical Engineering University of Hong Kong Hong KongP.R.China

This paper studies the control of chained nonholonomic systems by using smooth time-varying ***,by using a time-varying state transformation,the chained nonholonomic system is transformed into a linear time-varying ***,with the aid of some properties of a class of parametric Lyapunov equations and time-varying systems theory,smooth time-varying state feedback controller is developed to ensure the exponential convergence of both the system states and *** from existing results,the design parameters in the proposed control strategy are independent of the initial conditions of the ***,as an application of the proposed smooth time-varying feedback,the attitude control problem for underactuated axisymmetric spacecraft is ***,a numerical simulation is presented to validate the effectiveness of the proposed method.

关键词： Nonholonomic systems underactuated spacecraft attitude control smooth time-varying feedback parametric Lyapunov equations

Investigation multi-target synergistic mechanism of Choerospondias axillaris in the treat of cerebral ischemia based on systems pharmacology and experimental verification

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Natural Therapy Advances 2024年第3期7卷 37-47页

作者： Yang Ma min-Chun Chen Zuo-Yan Zhang kang-kang Yan Yi Ding Department of Pharmacy Xi'an No.3 Hospital the affiliated Hospital of Northwest UniversityXi’an 710000China Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’an 71000China

Background:Choerospondias axillaris(CA)is a traditional Mongolian medicine that has been proven to have a good therapeutic effect on cerebrovascular *** Ischemia(CI)is a severe and life-threatening cerebrovascular ***,the specific mechanism of action of CA in the treatment of CI is still ***:In this study,the related targets and pathways of CA in the treatment of CI were first predicted by system pharmacology and then verified by relevant ***:The results showed that 12 active ingredients and 208 targets were *** validation through protein-protein interaction(PPI)network analysis and active ingredients-target-pathway(A-T-P)network analysis has confirmed the pivotal roles of the main bioactive constituents,including quercetin,kaempferol,naringin,β-sitosterol,and gallic *** components exert their anti-ischemic effects by modulating key targets such as IL6,TNF,MAPK3,and CASP3,thereby regulating the PI3K-Akt,HIF-1,and MAPK signaling pathways,which are integral to processes like inflammation,apoptosis,and oxidative *** importantly,through experimental verification,this study confirmed our prediction that CAE significantly reduced neurological function scores,infarct volume,and the percentage of apoptosis ***:This indicates that CA acts on CI through multi-target synergistic mechanism,and this study provides theoretical basis for the clinical application of CA.

关键词： systems pharmacology Choerospondias axillaris cerebral ischemia multi-target synergistic mechanism middle cerebral artery occlusion

Polyoxometalates for continuous power generation by atmospheric humidity

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Nano Research 2024年第3期17卷 1875-1885页

作者： Tuo Ji Weilin Chen Zhenhui kang Liming Zhang Key Laboratory of Polyoxometalate and Reticular Material Chemistry of ministry of Education Northeast Normal UniversityChangchun 130024China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices DepartmentSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China Institute of Functional State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Atmospheric humidity is a sustainable low-value energy widely existing in natural environment,which is a promising candidate to solve the noncontinuous and low efficiency of low-value energy power *** the mono-substituted Dawson-type polyoxometalates are constructed to be highly dispersed organic ammonium-polyoxoanion clusters and are assembled into thin films power generators with micropores,working in atmospheric *** optimal polyoxometalates generator with the thickness of 7.2μm and the area of 0.36 cm^(2) produces a voltage of 0.68 V and a current density of 19.5μA·cm^(-2) under simulated natural environment,and works continuously and stably under almost all-natural environments(humidity 10%–90%).The highly dispersed polyoxometalate nanoclusters can form microporous in polyoxometalate films to effectively absorb atmospheric humidity and spontaneously form distribution gradient of water,which is the structural basis of power *** continuous power generation may be maintained by the effective adsorption and utilization of H_(2)O,the huge electrostatic field of organic ammonium-polyoxoanion clusters,and the reasonably designed polyoxometalates containing inorganic small ions with high *** is the first humidity generator designed with polyoxometalates,which may provide a new research direction for polyoxometalates in sustainable utilization of low-value energy.

关键词： atmospheric humidity continuous power generations nanomaterials polyoxoanions polyoxometalates

Transparent high-performance piezoceramics through pressureless sintering

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Journal of Advanced Ceramics 2024年第5期13卷 561-567页

作者： Hye-Lim Yu Woo-Seok kang Ju-Hyeon Lee Temesgen Tadeyos Zate Young-Jin Lee Bo-Kun Koo Dong-Jin Shin min-Soo Kim Soon-Jong Jeong Young Ghyu Ahn Wook Jo Department of Material Science and Engineering Ulsan National Institute of Science and TechnologyUlsan 44919Republic of Korea Energy Conversion Research Center Korea Electrotechnology Research InstituteChangwon 51543Republic of Korea MLCC Development Team Component Biz.UnitSamsung Electro-Mechanics Co.Ltd.Suwon 16674Republic of Korea

Piezoelectricity offers an electromechanical coupling that is widely utilized in transducer *** has been a consistent demand for transparent piezoelectric materials for optoelectrical ***,despite the inherent tradeoff between the transparency and the piezoelectricity,numerous strategies have been explored to develop the transparent piezoelectric ***,the most transparent piezoelectric materials developed to date is either a single crystal or materials that achieve transparency via hot-press sintering,limiting its industrial ***,we introduce a novel piezoelectric material that ensures transparency through co-doping and pressureless sintering of polycrystalline *** this study,we employed a compositional optimization approach to enhance the synergistic effect between the transparency and the piezoelectric properties of 0.71Pb(Mg_(1/3)Nb_(2/3))O_(3)–0.29PbTiO_(3)(PMN–0.29PT)*** utilizing the tape casting process for mass production and large-area manufacturing,our Pb_(0.913)La_(0.0145)Sm_(0.0145)(Mg_(1/3)Nb_(2/3))_(0.71)Ti_(0.29)O_(3)(TP2.9)ceramics exhibited over 60%transparency and large piezoelectric coefficient(d33)of 1104 pC/*** material holds considerable promise for a wide range of industrial applications in both the optical and electronic domains.

关键词： piezoelectric ceramics transparency pressureless sintering co-doping tape casting

MicroR-9c-5p and novel-mir50 co-target Akt to regulate Lasioderma serricorne reproduction

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Insect Science 2024年第1期31卷 106-118页

作者： Yi Yan Dong-Dong Qin Hong Yang kang-kang Xu Can Li Wen-Jia Yang Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and Economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

High fecundity is a common characteristic of insect pests which increases the difficulty of population ***/threonine kinase Akt is an indispensable component of the insulin signaling *** of LsAkt severely hinders reproduction in Lasioderma serricorne,a stored product insect ***,the post-transcriptional pathway of LsAkt in *** remains *** study identified 2 binding sites of miR-9c-5p and novel-mir50 in the coding sequences of *** expression profiles of 2 microRNAs(miRNAs)and LsAkt displayed an opposite pattern during the adult *** reporter assay showed that novel-mir50 and miR-9c-5p could downregulate the expression of *** of miR-9c-5p and novel-mir50 by injection of mimics inhibited the expression of LsAkt and reduced oviposition,decreased egg hatchability,and blocked ovarian *** also decreased the expression of genes involved in ovarian development(LsVg and LsVgR)and the nutritional signaling pathway(LsTOR,LsS6K,and Ls4EBP),and reduced the phosphorylation of ***,injection of miR-9c-5p and novel-mir50 inhibitors induced the expressions of LsAkt,LsVg,LsVgR,LsTOR,LsS6K,and Ls4EBP,enhanced Akt phosphorylation level,and accelerated ovarian *** of bovine insulin downregulated the expression of miR-9c-5p and novel-mir50 and upregulated the LsAkt *** also rescued the reproductive development defects associated with miR-9c-5p/novel-mir50 overexpression,forming a positive regulatory loop of insulin *** results indicate that miR-9c-5p/novel-mir50 regulates the female reproduction of *** by targeting Akt in response to insulin *** data also demonstrate the effects of the insulin/miRNA/Akt regulatory axis in insect reproduction.

关键词： Akt insulin Lasioderma serricorne microRNA reproduction

Occurrence of microplastics in natural and farmland soil in the Qilian Mountains of the Northern Tibetan Plateau

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Journal of Mountain Science 2024年第7期21卷 2159-2172页

作者： kang Qiangqiang ZHANG Yulan kang Shichang ZHANG Shengyin LUO Xi LI Longrui WANG Zhaoqing ZHANG Shuncun Key Laboratory of Petroleum Resources Exploration and Evaluation Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China

Microplastics(MPs)become ubiquitous in soil and are an environmental and public health concern ***,the status of MPs in natural and farmland soils in remote areas remains poorly *** this study,we investigated the characteristics of MPs in natural and farmland soils along two transects in the Qilian Mountains of the northern Tibetan *** average abundance of MPs in natural and farmland soils was 29,778 and 56,123 items kg^(-1),respectively,with a detection size range of 10-1000μ*** in the size range of 10-100μm accounted for 84.1%of particles *** the 21 polymers detected,polyethylene dominated in both farmland and natural *** shape of MPs was dominated by fragments(95.8%),followed by fibers(3.8%)and beads(0.4%).The abundance of MPs was positively correlated with increasing altitude in natural *** was no significant correlation between the abundance of MPs and soil physicochemical properties due to the narrow range of values of soil physicochemical *** the growing concern regarding MPs pollution,research on the status of MPs in high altitude and remote areas is critical to understanding their global cycle.

关键词： Microplastics pollution Soil Remote areas Tibetan Plateau

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

THE SCHUR TEST OF COMPACT OPERATORS

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Acta Mathematica Scientia 2024年第5期44卷 2041-2050页

作者： Qijian kang Maofa WANG School of Mathematics and Statistics Lingnan Normal UniversityZhanjiang524048China School of Mathematics and Statistics Wuhan UniversityWuhan430072China

Infinite matrix theory is an important branch of function *** linear operator on a complex separable infinite dimensional Hilbert space corresponds to an infinite matrix with respect a orthonormal base of the space,but not every infinite matrix corresponds to an *** classical Schur test provides an elegant and useful criterion for the boundedness of linear operators,which is considered a respectable mathematical *** this paper,we prove the compact version of the Schur ***,we provide the Schur test for the Schatten class S_(2).It is worth noting that our main results can be applicable to the general matrix without limitation on non-negative *** finally provide the Schur test for compact operators from l_(p) into l_(q).

关键词： Schur test compact operator infinite matrix

A review on the multi-scaled structures and mechanical/thermal properties of tool steels fabricated by laser powder bed fusion additive manufacturing

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International Journal of minerals,Metallurgy and Materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan kang Zehao Qin Mohamed El Mansori Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

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甘草柑橘皮果醋发酵工艺研究

粮食与油脂 2024年第7期37卷 63-69,87页

作者：亢敏山西工商学院山西太原030006

以柑橘皮为主料,甘草为辅料,采用液态发酵法制备甘草柑橘皮果醋。先以总黄酮含量为指标,在单因素试验的基础上通过响应面法优化酒精液制备工艺;再在最佳酒精液制备条件下,以总酸含量和感官评分为指标,通过响应面法优化果醋制备工艺,并... 详细信息

以柑橘皮为主料,甘草为辅料,采用液态发酵法制备甘草柑橘皮果醋。先以总黄酮含量为指标,在单因素试验的基础上通过响应面法优化酒精液制备工艺;再在最佳酒精液制备条件下,以总酸含量和感官评分为指标,通过响应面法优化果醋制备工艺,并对其理化及微生物指标进行分析。结果表明:酒精液最佳工艺参数为酵母菌接种量0.5%(以原料液体积为基准)、原料液糖度16%、发酵时间9 d,在此条件下果醋总黄酮含量为5.37%。最佳果醋制备参数为醋酸菌接种量2.0%(以酒精液体积为基准)、发酵温度35℃、初始乙醇体积分数8.5%、发酵时间9 d,在此条件下果醋总酸含量为5.61 g/100 mL,感官评分为8.74,微生物指标符合相关标准要求。

关键词：甘草柑橘皮果醋发酵工艺感官评分