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Structure optimization of the organ-pipe cavitating nozzle and its erosion ability test on hydrate-bearing sediments

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Petroleum Science 2023年第2期20卷 1104-1118页

作者： Xiao-ya Wu Yi-Qun Zhang Zhen-Qiang xu Shuai zhao Gen-Sheng Li Shou-Ceng Tian ya-Wen Tan Ke-Wen Peng College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China College of Safety and Ocean Engineering China University of Petroleum-BeijingBeijing102249China State Key Laboratory of Natural Gas Hydrate China University of Petroleum-BeijingBeijing102249China National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou Marine Geological SurveyGuangzhou510075GuangdongChina Guangdong Provincial Key Laboratory of Distributed Energy Systems Dongguan University of TechnologyDongguan523808GuangdongChina

Cavitating jet is a promising drilling rate improvement technology in both the marine natural gas hydrate (NGH) fluidization exploitation method and the integrated radial jet drilling and completion method. In present study, we aim to improve the efficiency of jet erosion and extracting NGH. With a computational fluid dynamics (CFD) method, the pressure, velocity and cavitation field characteristics of organ-pipe cavitating jet (OPCJ) are analysed. The divergent angle, throat length, and divergent length of OPCJ nozzle are preferred to obtain stronger jet cavitation erosion effect. Laboratory experiments of gas hydrate-bearing sediments (GHBS) erosion by OPCJ and conical jet (CJ) are conducted to compare and validate the jet erosion performance. The impinging models of OPCJ and CJ are constructed to study the impact characteristics. Results show that the preferred values of divergent angle, throat length, and divergent length are 15°, 1d, and 3d, respectively, in present simulation conditions. For GHBS, the OPCJ possesses the advantages of high efficiency and low energy consumption. Moreover, the OPCJ has higher penetration efficiency, while showing equivalent penetration ability compared to CJ. During the impinging process, the OPCJ can induce stronger impact pressure and turbulence effect, and also shows stronger chambering effect and bottom cleaning ability compared to CJ. This study presents the erosion performance of OPCJ and CJ on GHBS, and provides preliminary insights on the potential field applications in NGH exploitation.

关键词： Natural gas hydrate Cavitating jet Structure optimization Computational fluid dynamics Experimental study

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Acta Mathematica Sinica,English Series 2014年第10期30卷 1689-1697页

作者： Zhe DONG ya Fei zhao Department of Mathematics Zhejiang University

In this note, we show that avon Neumann algebra M is injective if and only if the weak＊ similarity degree d.（M） ≤ 2.

关键词： Weak* similarity degree injective von Neumann algebra operator space

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Enzymatic Determination of Glucose by Optical-Fiber Sensor Sequential Injection Renewable Surface Spectrophotometry

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Chemical Research in Chinese Universities 2006年第3期22卷 287-291页

作者： WANG Jian-ya FANG zhao-lun Research Center for Analytical Sciences Northeastern University Shenyang 110006 P. R. China School of Petrochemical Engineering Shenyang University of Technology Shenyang 111003 P. R. China

On the basis of oxidative decoloration of bromopyrogallol red （BPR） with H2O2, catalyzed by horseradish peroxidase（ HRP）, and the sequential injection renewable surface technique（ SI-RST）, a highly sensitive optical-fiber sensor spectrophotometric method for the enzymatic determination of hydrogen peroxide was proposed. By coupling with a glucose oxidase（GOD）-catalyzed reaction, the method was used to determine glucose in human serum. The considerations in system and flow cell design, and factors that influence the determination performance are discussed. With 100μL of sample loaded and 0. 6 mg of bead trapped, the linear response range from 5.0 × 10^-8 to 5.2 × 10^-6 mol/L BPR with a detection limit（3σ） of 2. 5 ×10 ^-8 mol/L BPR, and a precision of 1.1% RSD（ n = 11 ） and a throughput of a 80 samples per hour can be achieved. Under the conditions of a 8. 7 × 10^ -6 mol/L BPR substrate, 0. 04 unit/mL HRP, 600 s reaction time and a reaction temperature of 37℃, the linear response range for H2O2 was from 5.0 × 10^-8 to 7.0 × 10^-6 mol/L with a detection limit（3σ） of 1.0 × 10^-8 mol/L and a precision of 3.7% RSD （ n = 11 ）. The linear response range by coupling with a GOD-catalyzed reaction was from 1.0 × 10^-7 to 1.0 × 10^-5 mol/L. The method was directly applied to determine glucose in human serum. Glucose contents obtained by the proposed procedure were compared with those obtained by using the phenol-4-AAP method, the error was found to be less than 3%.

关键词： Sequential injection renewable surface Optical-fiber sensor Enzymatic reaction Glucose

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Syntheses and Structures of Two Coordination Polymers Containing Macrocyclic Oxamide and Isophthalic Acid Derivatives

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Chemical Research in Chinese Universities 2012年第5期28卷 775-779页

作者： WU Lin SUN ya-qiu LIU Xiao-xu GA0 Dong-zhao xu yan-yan ZHANG Guo-ying Tianjin Key Laboratory of Structure and Performance for Functional Molecule College of ChemistryTianjin Normal UniversityTianjin 300387P.R.China

Two novel coordination polymers [Cd（NiL）（aipt）]（1） and [Mn（nipt）（NiL）2]？H2O（2）（NiL, H2L=2,3-dioxo- 5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2aipt=5-aminoisophthalic acid, H2nipt=5-nitroisoph- thalic acid） were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 consist of different 1D chains including both oxamide and 5-aminoisophthalate or 5-nitroisophthalic bridge. And all these chains were further interlinked via hydrogen bonds, resulting in a 2D architecture in compounds 1 and 2.

关键词： Macrocyclic oxamide complex 5-Aminoisophthalic acid 5-Nitroisophthalic acid Heterometallic complex Polynuclear complex

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H lder Continuity of Weak Solutions for Parabolic Equations with Nonstandard Growth Conditions

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Acta Mathematica Sinica,English Series 2006年第3期22卷 793-806页

作者： Meng xu ya Zhe CHEN School of Mathematical Sciences Peking University Department of Applied Mathematics Nanjing University of Science and Technology

In this paper, we investigate the interior regularity including the local boundedness and the interior HSlder continuity of weak solutions for parabolic equations of the p（x, t）-Laplacian type. We improve the Moser iteration technique and generalize the known results for the elliptic problem to the corresponding parabolic problem.

关键词： Boundedness Hoelder continuity Parabolic equations Nonstandard growth conditions

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Certain averaging operators on Triebel-Lizorkin spaces

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Applied Mathematics(A Journal of Chinese Universities) 2022年第4期37卷 546-562页

作者： zhao Jun-yan PAN ya-li College of Mathematics and Computer Science Zhejiang Normal UniversityJinhua 321004China Department of Mathematics School of InformationHuaibei Normal UniversityHuaibei 235000China

In this article,we study the boundedness properties of the averaging operator S_(t)^(γ) on Triebel-Lizorkin spaces F_(p,q)^(α)(R^(n))for various p,*** an application,we obtain the norm convergence rate for S_(t)^(γ)(f)on Triebel-Lizorkin spaces and the relation between the smoothness imposed on functions and the rate of norm convergence of S_(t)^(γ) is given.

关键词： spherical mean Triebel-Lizorkin spaces norm convergence saturation of approximation Bessel function wave operator oscillatory integrals

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Theoretical analysis of the coupling between Feshbach states and hyperfine excited states in the creation of 23Na40K molecule

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Chinese Physics B 2020年第2期29卷 218-223页

作者： ya-Xiong Liu Bo zhao Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaShanghai 201315China

We present an intensive study of the coupling between different Feshbach states and the hyperfine levels of the excited states in the adiabatic creation of 23Na40K ground-state *** use coupled-channel method to calculate the wave function of the Feshbach molecules,and give the short-range wave function of triplet *** energies of the hyperfine excited states and the coupling strength between the Feshbach states and the hyperfine excited states are *** results can be used to prepare a specific hyperfine level of the rovibrational ground state to study the ultracold collisions involving molecules.

关键词： Feshbach resonance stimulated Raman adiabatic passage ultracold molecule

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Martensitic transformation and magnetic properties in Mn_(49-x)Cu_(x)Ni_(41)Sn_(10)(x=0-2)

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Rare Metals 2023年第7期42卷 2433-2438页

作者： Meng-Zhe zhao Hong-Mei Qiu Ze-ya Zhu Yun-Li xu Zhu-Hong Liu Li-Qing Pan Department of Applied Physics University of Science and Technology BeijingBeijing100083China College of Science China Three Gorges UniversityYichang443002China

The crystal structure,phase transition,metamagnetic behavior and magnetic entropy change(ΔS_(M))of the Mn_(49-x)Cu_(x)Ni_(41)Sn_(10)(x=0-2)alloys were systematically *** results of experiment about crystal structure confirm that Mr_(49-x)Cu_(x)Ni_(41)Sn_(10)alloys have a highly ordered cubic L2_(1)Heusler *** Cu element improving,all samples have a martensitic transformation and inverse martensitic transformation by analyzing the result of magnetic *** saturation magnetization of samples decreases gradually,the martensitic transformation temperature(T_(M))of as-annealed samples increases to a high-temperature area,and the Curie temperature(T_(C))of samples moves to a low-temperature area with the content of Cu element increasing from x=0 to x=*** positive values of magnetic entropy change(ΔS_(M))of all alloys were investigated near the martensitic *** the applied magnetic field is 3 T,a worthwhile value ofΔS_(M)can reach up to 32.0 J·kg^(-1)·K^(-1)in Mn_(47)Cu_(2)Ni_(41)Sn_(10)alloy.

关键词： Heusler alloys Arc melting X-ray diffraction Magnetic properties

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Scutellaria baicalensis, the golden herb from the garden of Chinese medicinal plants

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Science Bulletin 2016年第18期61卷 1391-1398页

作者： Qing zhao Xiao-ya Chen Cathie Martin Plant Science Research Center Shanghai Chenshan Botanical Garden Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai 201602 China Department of Metabolic Biology John Innes CentreNorwich NR4 7UH UK Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China

Scutellaria baicalensis Georgi, or Chinese skullcap, has been widely used as a medicinal plant in China for thousands of years, where the preparation from its roots is called Huang-Qin. It has been applied in the treatment of diarrhea, dysentery, hypertension, hemorrhaging, insomnia,inflammation and respiratory infections. Flavones such as baicalin, wogonoside and their aglycones baicalein wogonin are the major bioactive compounds extracted from the root of S. baicalensis. These flavones have been reported to have various pharmacological functions, including anti-cancer,hepatoprotection, antibacterial and antiviral, antioxidant,anticonvulsant and neuroprotective effects. In this review,we focus on clinical applications and the pharmacological properties of the medicinal plant and the flavones extracted from it. We also describe biotechnological and metabolic methods that have been used to elucidate the biosynthetic pathways of the bioactive compounds in Scutellaria.

关键词： Scutellaria baicalensis Flavonoids Anti-cancer Metabolic biology Medicinal plants

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Phrenic and intercostal nerves with rhythmic discharge can promote early nerve regeneration after brachial plexus repair in rats

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Neural Regeneration Research 2018年第5期13卷 862-868页

作者： Jing Rui ya-Li xu Xin zhao Ji-Feng Li Yu-Dong Gu Jie Lao Department of Hand Surgery Huashan Hospital Fudan University Shanghai China Key Laboratory of Hand Reconstruction Ministry of Health Shanghai China Shanghai Key Laboratory of Peripheral Nerve and Microsurgery Shanghai China

Exogenous discharge can positively promote nerve repair. We, therefore, hypothesized that endogenous discharges may have similar effects. The phrenic nerve and intercostal nerve, controlled by the respiratory center, can emit regular nerve impulses; therefore these endogenous automatically discharging nerves might promote nerve regeneration. Action potential discharge patterns were examined in the diaphragm, external intercostal and latissimus dorsi muscles of rats. The phrenic and intercostal nerves showed rhythmic clusters of discharge, which were consistent with breathing frequency. From the first to the third intercostal nerves, spontaneous discharge amplitude was gradually increased. There was no obvious rhythmic discharge in the thoracodorsal nerve. Four animal groups were performed in rats as the musculocutaneous nerve cut and repaired was bland control. The other three groups were followed by a side-to-side anastomosis with the phrenic nerve, intercostal nerve and thoracodorsal nerve. Compound muscle action potentials in the biceps muscle innervated by the musculocutaneous nerve were recorded with electrodes. The tetanic forces of ipsilateral and contralateral biceps muscles were detected by a force displacement transducer. Wet muscle weight recovery rate was measured and pathological changes were observed using hematoxylin-eosin staining. The number of nerve fibers was observed using toluidine blue staining and changes in nerve ultrastructure were observed using transmission electron microscopy. The compound muscle action potential amplitude was significantly higher at 1 month after surgery in phrenic and intercostal nerve groups compared with the thoracodorsal nerve and blank control groups. The recovery rate of tetanic tension and wet weight of the right biceps were significantly lower at 2 months after surgery in the phrenic nerve, intercostal nerve, and thoracodorsal nerve groups compared with the negative control group. The number of myelinated axons d

关键词： nerve regeneration endogenous automatic discharge side-to-side nerve anastomosis peripheral nerve regeneration phrenic nerve intercostal nerve peripheral nerve injury neural regeneration

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