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Biomimetic soft robotic wrist with 3-DOF motion and stiffness tunability based on ring-reinforced pneumatic actuators and a particle jamming joint

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Science china(Technological Sciences) 2024年第3期67卷 774-790页

作者： HU TeTe LU xinjiang YI Jian WANG YuHui XU Du State Key Laboratory of Precision Manufacturing for Extreme Service Performance School of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China

The human wrist, a complex articulation of skeletal muscles and two-carpal rows, substantially contributes to improvements in maneuverability by agilely performing three-degree-of-freedom(3-DOF) orienting tasks and regulating stiffness according to variations in interaction forces. However, few soft robotic wrists simultaneously demonstrate dexterous 3-DOF motion and variable stiffness;in addition, they do not fully consider a soft-rigid hybrid structure of integrated muscles and two carpal *** this study, we developed a soft-rigid hybrid structure to design a biomimetic soft robotic wrist(BSRW) that is capable of rotating in the x and y directions, twisting around the z-axis, and possessing stiffness-tunable capacity. To actuate the BSRW, a lightweight soft-ring-reinforced bellows-type pneumatic actuator(SRBPA) with large axial, linear deformation(η_(lcmax)=70.6%,η_(lemax)=54.3%) and small radial expansion(η_(demax)=3.7%) is designed to mimic the motion of skeletal muscles. To represent the function of two-carpal rows, a compact particle-jamming joint(PJJ) that combines particles with a membrane-covered ballsocket mechanism is developed to achieve various 3-DOF motions and high axial load-carrying capacity(>60 N). By varying the jamming pressure, the stiffness of the PJJ can be adjusted. Finally, a centrally positioned PJJ and six independently actuated SRBPAs, which are in an inclined and antagonistic arrangement, are sandwiched between two rigid plates to form a flexible,stable, and compact BSRW. Such a structure enables the BSRW to have a dexterous 3-DOF motion, high load-carrying ability,and stiffness tunability. Experimental analysis verify 3-DOF motion of BSRW, producing force of 29.6 N and 36 N and torque of2.2 Nm in corresponding rotations. Moreover, the range of rotational angle and stiffness-tuning properties of BSRW are studied by applying jamming pressure to the PJJ. Finally, a system combining a BSRW and a soft enclosing gripper is proposed to demo

关键词： pneumatic soft actuators particle jamming robotic wrist soft robotics stiffness-tunable

Formation of bulk ferromagnetic nanostructured Fe_(40)Ni_(40)P_(14)B_6 alloys by metastable liquid spinodal decomposition

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Science china(Technological Sciences) 2009年第7期52卷 1919-1922页

作者： LI Qiang1,2 1 School of physics Science and Technology, xinjiang university, urumqi 83004., china 2 department of physics, The Chinese university of HongKong, Shatin N.T., HongKong, china School of physics Science and Technology Xinjiang University Urumqi China department of physics The Chinese University of HongKong Shatin N.T. HongKong China

Nanostructured Fe40Ni40P14B6 alloy ingots of 3―5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 260 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>290 K, the overall microstructure of the specimen changed into a granular morphology. The average grain sizes of the small and large grains are 30 nm and 80 nm, respectively. These prepared samples are soft magnets with saturation magnetization Bs 0.744 T.

关键词： nanomaterials magnetic materials solidification bulk nanostructured alloy Fe40Ni40P14B6 metastable liquid spinodal decomposition

Solvothermal synthesis of nanocrystalline FeS_2

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 188-200页

作者： CHEN Yanhua1, ZHENG Yufeng1, ZHANG Xiaogang2, SUN Yanfei1 & DONG Youzhong11. physics department of xinjiang university, urumqi 83004., china 2. Institute of Applied Chemistry of xinjiang university, urumqi 83004., china physics department of xinjiang university Urumqi China Institute of Applied Chemistry of xinjiang university Urumqi China

This paper reports on the synthesis of the nanocrystalline FeS2 via a solvent-thermal process. Using FeSO4 and NH2CSNH2 as precursors and polyvinyl- pyrrolidone (PVP) as a protective agent (dispersant), we have successfully synthesized nanocrystalline FeS2 both under acidic conditions (pH = 5) and under alkali conditions (pH = 10) at various temperatures and for different time in alcohol-water solution. X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Ultraviolet Visible (UV-VIS) spectroscopy were used to characterize the morphology, structure, particle size and optical characterization of sample synthesized under acidic condition, and the XRD pattern was refined by Rietveld method. The experimental result shows that nanocrystalline FeS2 with uniform size, highly crystallized quality and excellent dispersivity has been synthesized at 200℃for 36 h.

关键词： FeS2 (Pyrite), solvothermal, PVP, the Rietveld method.

Ecological-breaking zone originates and its ecosystems reconstruction in arid area

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Journal of Environmental Sciences 1996年第2期8卷 203-211页

作者： Huang Peiyou Lu Zili(Biology department of xinjiang university,urumqi 83004.,china) Biology department Xinjiang University Urumqi 830046 China

In the process of arid land exploitation, the landscape of desert is divided into three types. Oasis is rising,the area of uneffected area keeps its original state,the serious degenerated area where is only limited between oasis and desert, but not overall. Its relationship with the neighbor region, the zone of ecological-breaking region or ecological rift valley is not successive. . Its ecological effect endangered the arid land overall. Rehabilitating vegetation is the basic measure for abatement. The authors proposed a new tactics that based on the properties of vegetation. Depending on the local water sources and partly regulating the composition of environmental factor to satisfy the requirement of desert community, the rehabilitate vegetation should be realized.

关键词： arid area ecological-breaking zone ecosystems reconstruction.

Identifying the geographical origin and processing technology of Moyao(Myrrh)on the basis of near-infrared spectroscopy combined with chemometrics

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Journal of Traditional Chinese Medicine 2024年第3期44卷 505-514页

作者： XU Ningning YAN Ganming XU Fengjie DENG Linfeng QIAO xinjiang LU Changzheng CHENG Shaomin TCM Diagnosis Institute College of Traditional Chinese MedicineJiangxi University of Chinese MedicineNanchang 330004China TCM Processing Institute Pharmaceutical CollegeJiangxi University of Chinese medicineNanchang 330004China School of Electronic Information and Artificial Intelligence Shaanxi University of Science and TechnologyXi'an 710021China Jiangzhong Pharmaceutical Co. Ltd.Nanchang 330096China Jiangxi Guhan Refined Chinese Herbal Pieces Co. Ltd.Nanchang330041.China

OBJECTIVE:To evaluate the quality of Moyao(Myrrh)in the identification of the geographical origin and processing of the ***:Raw Moyao(Myrrh)and two kinds of Moyao(Myrrh)processed with vinegar from three countries were identified using near-infrared(NIR)spectroscopy combined with chemometric *** component analysis(PCA)was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories.A classical chemometric algorithm(PLS-DA)and two machine learning algorithms[K-nearest neighbor(KNN)and support vector machine]were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh)samples,and their discriminative performance was ***:Based on the accuracy,precision,recall rate,and F1 value in each model,the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive *** all of the chemometric analyses,the NIR spectrum of Moyao(Myrrh)preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins,and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the *** best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 ***:NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh)and can also provide a reference for evaluations of its quality and the clinical use.

关键词： Moyao(Myrrh) near-infrared spectroscopy geographical origin processing technology

THE NEAR-CRITICAL AND SUPER-CRITICAL ASYMPTOTIC BEHAVIOR IN THE THERMODYNAMIC LIMIT OF REVERSIBLE RANDOM POLYMERIZATION PROCESSES

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Acta Mathematica Scientia 2000年第3期20卷 380-389页

作者：韩东 department of Mathematics University of Xinjiang Urumqi 830046 China

In this paper, the near-critical and super-critical asymptotic behavior of a reversible Markov process as a chemical model for polymerization was studied. The results of the present paper, together with an analysis of the sub-critical stage, establish the existence of three distinct stages (sub-critical, near-critical and super-critical stages) of polymerization (in the thermodynamic limit as N --> +infinity,),depending on the value of strength of the fragmentation reaction. These three stages correspond to the size of the largest length of polymers of size N to be itself of order log N, Nm/m+1 (m greater than or equal to 2, m not equal 4n, n greater than or equal to 1) and N, respectively.

关键词： polymerization Markov process limit behavior stationary distribution

FeS_(2) (pyrite) electrodeposition thin films and study of growth mechanism

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Science china(Technological Sciences) 2005年第6期48卷 601-611页

作者： DONG Youzhong1, ZHENG Yufeng1, ZHANG Xiaogang2, DUAN He1, SUN Yanfei1 & CHEN Yanhua1 1. department of physics, xinjiang university, urumqi 83004., china 2. Institute of Applied Chemistry, xinjiang university, urumqi 83004., china department of physics Xinjiang University Urumqi China Institute of Applied Chemistry Xinjiang University Urumqi China

Ferrous sulfide (FeS) thin films were initially electrodeposited on indium-tin oxide (ITO) substrates in the aqueous solution containing iron, sulfur elements and then annealed in the sulfur atmosphere. Thereby, we successfully obtained the single-phased iron pyrite (FeS2) thin films with good quality. The experimental parameters for electrodeposition and the post-growth thermal-dynamical conditions have been calculated so that more details about the effect of thermal-dynamical conditions on the micromechanism concerned with the iron pyrite crystal growth as well as the properties of the samples have been discussed.

关键词： electrodeposition, FeS2 (pyrite), thin films, growth dynamics.

New Hardy Spaces Associated with Herz Spaces and Beurling Algebras on Homogeneous Groups

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Acta Mathematica Sinica,English Series 2002年第4期18卷 661-670页

作者： Yin Sheng JIANG department of Mathematics. xinjiang university, urumqi, 83004., P. R. china department of Mathematics Xinjiang University Urumqi P. R. China

The author introduces the Hardy spaces associated with the Herz spaces and the Beurling algebras on homogeneous groups and establishes their atomic decomposition characterizations. As the applications of this decomposition, the duals of these Hardy spaces and the boundedness of the central δ-Calderon-Zygmund operators on these Hardy spaces are studied.

关键词： Homogeneous group Hardy spaces Herz spaces Beurling algebras Central atoms

The Silk Road and East-West Cultural Exchange

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china Book International 2024年第2期 52-57页

作者： Rong xinjiang department of History Peking University Center for Ancient Chinese History Peking University British Academy Dunhuang and Turpan Society of china

To the east and south of china lies the ocean,to the west are deserts and mountains,and to the north are the Gobi Desert and forests,placing it in a relatively enclosed geographical environment,which is not conducive to communication with the outside ***,china has never been self-isolated;through both the terrestrial and maritime Silk Road,it has maintained extensive contact with the external world,both contributing to and absorbing *** the historical process of East-West cultural exchange,the Silk Road played an extremely important role.

关键词： Silk West maintained