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Chinese Journal of Aeronautics 2021年第1期34卷 1-9页

作者： Jing CUI tao SHEN tao WEI Zhongyi CHU School of Mechanical Engineering and Applied Electronics Beijing University of TechnologyBeijing 100124China School of Instrumental Science ami Opto-electronics Engineering Beihang UniversityBeijing 100191China Shenzhen Polytechnic Shenzhen 518055China

The space debris occupies the orbit resources greatly,which seriously threats the safety of spacecraft for its high risks of *** theories about space debris removal have been put forward in recent *** Electro Dynamic Tether(EDT),which can be deployed under gravity gradient,is considered to be an effective method to remove debris in low orbit for its low power ***,in order to generate sufficient Lorentz force,the EDT needs to be deployed to several kilometers,which increases the risks of tangling and the instability of the EDT *** the deployment process,different initial in-plane/out-of-plane angles,caused by direction error at initial release or the initial selection of ejection,affect the motion of EDT system *** order to solve these problems,firstly,this paper establishes the dynamic model of the EDT ***,based on the model,safety metrics of avoiding tangling and assessing system stability during EDT deployment stage are designed to quantitatively evaluate the EDT system ***,several numerical simulations are established to determine the safety ranges of the initial in-plane/out-of-plane angles on the EDT deployment.

关键词： Assembly the electrodynamics tether system Electrodynamics tether deployment In-plane/out-of-plane angles Tangling risks

Degradation of organics using LaFeO_(3)as a persulfate activator under low-intensity ultra-violet-light irradiation:Catalytic performance and mechanism

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Journal of Rare Earths 2022年第7期40卷 1043-1052页

作者： Yumei Li Jian Fan Xiaonan Feng tao tao School of Environment Huazhong University of Science and TechnologyWuhan 430074China School of Energy and Environment Inner Mongolia University of Science and TechnologyBaotou 014010China

ABO_(3)-type perovskite oxides with abounding defect structures and diverse physical chemistry attributes have been extensively studied in heterogeneous *** LaFeO_(3)perovskites fabricated via the sol-gel method were used as peroxydisulfate(PDS)activators for methylene blue(MB)degradation under low-intensity ultra-violet(UV)-light to evaluate the degradation efficiency of organic pollutants and *** results indicate that under low-intensity UV irradiation,the developed UV/LaFeO_(3)/PDS system shows excellent degradation ability of organic pollutants in a wide pH *** spin resonance and radical quenching experiments verify that SO_(4)^(·-),·OH,h^(+)and ^(1)O_(2)are generated during the activation process,and ^(1)O_(2)plays a dominant role in MB *** of low oxidation state Fe(Ⅱ)and O_(2)^(2-)/O^(-)on the LaFeO_(3)surface shows that oxygen vacancy,as the electron transfer mediator,enhances the redox cycle efficiency of Fe(Ⅱ)/Fe(Ⅲ).Photogenerated electrons of LaFeO_(3)involved in the cyclic transformation of Fe(Ⅱ)/Fe(Ⅲ)and PDS activation further increase the number of active radicals and thus promote the synergistic effect of photocatalytic coupled with sulfate radicalbased advanced oxidation processes.

关键词： LaFeO_(3) Peroxydisulfate Singlet oxygen Low-intensity UV-light Rare earths

Endocrine aberrations of human nonobstructive azoospermia

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Asian Journal of Andrology 2022年第3期24卷 274-286页

作者： Yong tao Ottawa Fertility Center 955 Green Valley CrescentOttawaON K2C 3V4Canada

Nonobstructive azoospermia(NOA)refers to the failure of spermatogenesis,which affects approximately 1%of the male population and contributes to 10%of male *** has an underlying basis of endocrine imbalances since proper human spermatogenesis relies on complex regulation and cooperation of multiple hormones.A better understanding of subtle hormonal disturbances in NOA would help design and improve hormone therapies with reduced risk in human fertility *** purpose of this review is to summarize the research on the endocrinological aspects of NOA,especially the hormones involved in hypothalamic–pituitary–testis axis(HPTA),including gonadotropin-releasing hormone,follicle-stimulating hormone,luteinizing hormone,prolactin,testosterone,estradiol,sex hormone binding globulin,inhibin B,anti-Müllerian hormone,and *** the NOA men associated with primary testicular failure,the quality of currently available evidence has not been sufficient enough to recommend any general hormone optimization *** other NOA patients,especially those with hypogonadotropic hypogonadism,could be treated with hormonal *** these approaches have succeeded in resuming the fertility in many NOA patients,the prudent strategies should be applied in individuals according to specific NOA etiology by balancing fertility benefits and potential *** review also discusses how NOA can be induced by immunization against hormones.

关键词： endocrine follicle-stimulating hormone gonadotropin-releasing hormone inhibin B nonobstructive azoospermia prolactin sperm retrieval testosterone

A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： tao HAO School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

Positive-instantaneous frequency and approximation

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Frontiers of Mathematics in China 2022年第3期17卷 337-371页

作者： tao QIAN Macao Center for Mathematical Science Macao University of Science and TechnologyMacaoChina

Positive-instantaneous frequency representation for transient signals has always been a great concern due to its theoretical and practical importance,although the involved concept itself is *** desire and practice of uniqueness of such frequency representation(decomposition)raise the related topics in *** approximately the last two decades there has formulated a signal decomposition and reconstruction method rooted in harmonic and complex analysis giving rise to the desired signal *** method decomposes any signal into a few basic signals that possess positive instantaneous *** theory has profound relations to classical mathematics and can be generalized to signals defined in higher dimensional manifolds with vector and matrix values,and in particular,promotes kernel approximation for multi-variate *** article mainly serves as a *** also gives two important technical proofs of which one for a general convergence result(Theorem 3.4),and the other for necessity of multiple kernel(Lemma 3.7).Expositorily,for a given real-valued signal f one can associate it with a Hardy space function F whose real part coincides with *** function F has the form F=f+iHf,where H stands for the Hilbert transformation of the *** develop fast converging expansions of F in orthogonal terms of the form F=∑k=1^(∞)c_(k)B_(k),where B_(k)'s are also Hardy space functions but with the additional properties B_(k)(t)=ρ_(k)(t)e^(iθ_(k)(t)),ρk≥0,θ′_(k)(t)≥0,*** original real-valued function f is accordingly expanded f=∑k=1^(∞)ρ_(k)(t)cosθ_(k)(t)which,besides the properties ofρ_(k)andθ_(k)given above,also satisfies H(ρ_(k)cosθ_(k))(t)ρ_(k)(t)sinρ_(k)(t).Real-valued functions f(t)=ρ(t)cosθ(t)that satisfy the conditionρ≥0,θ′(t)≥0,H(ρcosθ)(t)=ρ(t)sinθ(t)are called *** f is a mono-component,then the phase derivativeθ′(t)is defined to be instantaneous frequency of *** above described positive-instantaneou

关键词： Möbius transform blaschke product mono-component hilbert transform hardy space inner and outer functions adaptive fourier decomposition rational orthogonal system nevanlinna factorization beurling-lax theorem reproducing kernel hilbert space several complex variables Clifford alge-bra pre-orthogonal AFD

An innovative flake graphite upgrading process based on HPGR,stirred grinding mill, and nanobubble column flotation

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International Journal of Mining Science and Technology 2021年第6期31卷 1063-1074页

作者： Fangyuan Ma Dongping tao Youjun tao Shuyong Liu Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education School of Chemical Engineering and TechnologyChina University of Mining and TechnologyXuzhou 221116China School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China School of Mining Engineering University of Science&Technology LiaoningAnshan 114051China

Physical upgrading of graphite is typically achieved with many stages of grinding and flotation to produce a concentrate with approximately 95% carbon *** innovative grinding and column flotation process has been developed for efficient graphite upgrading to substantially simplify the process flowsheet and reduce operating *** this process,a high-pressure grinding roller(HPGR) and a stirred mill were employed as primary comminution techniques and a nanobubble flotation column as a key separation *** results obtained with a crystalline flake graphite sample with a carbon grade of 11.15% show that the novel process can produce a concentrate with 94.82% carbon grade and 97.89% recovery from an open circuit of one rougher and two cleaner flotation *** electron microscope(SEM)microphotographs indicate that HPGR offers the advantage of more effective protection of graphite flakes during *** test results show that stirred mill could not only protect graphite flakes but also promote the efficient liberation of *** with the traditional flotation process,nanobubble flotation can effectively recover ultrafine *** new process possesses a number of important advantages over the traditional method,including substantially higher graphite recovery,greatly simplified process flowsheet,better protection of flake size,reduced reagent consumption and process costs,etc.

关键词： Column flotation Graphite HPGR Microbubbles Nanobubbles Stirred mill

Simplified procedure for controlling pressure distribution of a scramjet combustor

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Chinese Journal of Aeronautics 2014年第5期27卷 1137-1141页

作者： Cui tao School of Energy Science and Engineering Harbin Institute of Technology

Scramjet engines are used at extreme temperatures and velocity. New control problems involving distributed parameter control have been found concerning investigations of the control of scramjet engines whose physical states are spatially interacted. Succeeding the existing theoretical studies on the distributed parameter control for scramjet engines, this paper puts forward a simplified distributed parameter control approach for scramjet engines aimed at engineering application. The simplified control procedure uses the classical proportional-integral（PI） compensation to control the target pressure distribution of scramjet engines, which is effective and applicable for practical implements. Simulation results show the validation of the simplified distributed parameter control procedure.

关键词： Aeroengine Control Modeling Scramjet engine Supersonic combustion

Quantum measurement in coherence-vector representation

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Science China(Physics,Mechanics & Astronomy) 2016年第4期59卷 8-12页

作者： tao Zhou School of Physical Science and Technology Southwest Jiaotong University

We consider the quantum measurements on a finite quantum system in coherence-vector representation. In this representation, all the density operators of an N-level(N≥2) quantum system constitute a convex set M^(N)embedded in an(N^2- 1)-dimensional Euclidean space R^((N^2)-1), and we find that an orthogonal measurement is an(N- 1)-dimensional projector operator on R^((N^2)-1). The states unchanged by an orthogonal measurement form an(N- 1)-dimensional simplex, and in the case when N is prime or power of prime, the space of the density operator is a direct sum of(N + 1) such simplices. The mathematical description of quantum measurement is plain in this representation, and this may have further applications in quantum information processing.

关键词： quantum measurement coherence-vector representation geometry

Microstructure and Mechanical Properties of 1,000 MPa Ultra-High Strength Hot-Rolled Plate Steel for Coal Mine Refuge Chamber

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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 422-429页

作者： Changsheng Li Biao Ma tao Li tao Zhu State Key Laboratory of Rolling and Automation Northeastern University

The 1,000 MPa ultra-high strength hot-rolled plate steel with low-carbon bainitic microstructure was developed in the laboratory for coal mine refuge chamber. The static recrystallization behavior, microstructure evolution, and mechanical properties of this hot-rolled plate steel were investigated by the hot compression, continuous cooling trans- formation, and tensile deformation test. The results show that the developed steel has excellent mechanical properties at both room and elevated temperature, and its microstructure mainly consists of lath bainite, granular bainite, and ferrite after thermal-mechanical control process （TMCP）. The ultra-high strength plate steel is obtained by the TMCP process in hot rolling, strengthened by bainitic transformation, microstructure refinement, and precipitation of alloying elements such as Nb, Ti, Mo, and Cu. The experimental steel has relatively low welding crack sensitivity index and high atmospheric corrosion resistance index. Therefore, the developed steel has a good balance of strength and ductility both at room and elevated temperature, weldability and corrosion resistance, and it can suffice for the basic demands for materials in the manufacture of coal mine refuge chamber.

关键词： Ultra-high strength steel Low-carbon bainite Coal mine refuge chamber Microstructure Mechanical property

Tibetan Plateau: An evolutionary junction for the history of modern biodiversity

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Science China Earth Sciences 2020年第2期63卷 172-187页

作者： tao DENG Feixiang WU Zhekun ZHOU tao SU Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesXishuangbanna 666303China

Holding particular biological resources,the Tibetan Plateau is a unique geologic-geographic-biotic interactively unite and hence play an important role in the global biodiversity *** Tibetan Plateau has undergone vigorous environmental changes since the Cenozoic,and played roles switching from"a paradise of tropical animals and plants"to"the cradle of Ice Age mammalian fauna".Recent significant paleontological discoveries have refined a big picture of the evolutionary history of biodiversity on that plateau against the backdrop of major environmental changes,and paved the way for the assessment of its far-reaching impact upon the biota around the plateau and even in more remote ***,based on the newly reported fossils from the Tibetan Plateau which include diverse animals and plants,we present a general review of the changing biodiversity on the Tibetan Plateau and its influence in a global *** define the Tibetan Plateau as a junction station of the history of modern biodiversity,whose performance can be categorized in the following three patterns:(1)Local origination of endemism;(2)Local origination and"Out of Tibet";(3)Intercontinental dispersal via *** first pattern is exemplified by the snow carps,the major component of the freshwater fish fauna on the plateau,whose temporal distribution pattern of the fossil schizothoracines approximately mirrors the spatial distribution pattern of their living *** ascent with modification,their history reflects the biological responses to the stepwise uplift of the Tibetan *** second pattern is represented by the dispersal history of some mammals since the Pliocene and some *** ancestors of some Ice Age mammals,e.g.,the wholly rhino,Arctic fox,and argali sheep first originated and evolved in the uplifted and frozen Tibet during the Pliocene,and then migrated toward the Arctic regions or even the North American continent at beginning of the Ice Age;the ancestor of panthe

关键词： Tibetan Plateau Cenozoic Biodiversity Evolution Plants Fish Mammals