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Effect of chlorine content of chlorophenols on their adsorption by mesoporous SBA-15

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Journal of Environmental Sciences 2012年第8期24卷 1411-1417页

作者： qingdong qin ke Liu Dafang Fu Haiying Gao School of Civil Engineering Southeast UniversityNanjing 210096China Department of Man-Machine and Environment Engineering Nanfing University of Aeronautics and AstronauticsNanfing 210016China

Studies on the effect of the chlorine content of chlorophenols （CPs） on their adsorption from aqueous solution by mesoporous SBA-15 are important in understanding the mechanisms of CP adsorption. In this study, three CPs with different degrees of chlorine content （i.e., 2-chlorophenol, 2,6-dichlorophenol and 2,4,6-trichlorophenol） were investigated. The effects of parameters such as temperature and solution pH were studied. The results showed that CP adsorption by SBA- 15 increased with increasing number of chlorine substituents and depended strongly on the temperature and solution pH. Thermodynamic parameters such as Gibbs free energy change （AGO）, enthalpy change （△H^0） and entropy change （△S^0） were also calculated. By comparison of the adsorption coefficient of CPs with varying physical-chemical properties （size, hydrophobicity and electron density）, we propose that hydrophobic interactions between CPs and the SBA-15 surface, as well as electron donor-acceptor （EDA） complexes between oxygen of the siloxane surface of SBA-15 （e--donor） and the n-system of the CPs （e--acceptor）, were dominant adsorption mechanisms.

关键词： chlorophenols mesoporous SBA-15 adsorption pH temperature

A new robust design for imperfection sensitive stiffened cylinders used in aerospace engineering

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Science China(Technological Sciences) 2015年第5期58卷 796-802页

作者： LIANG ke ZHANG YongJie SUN qin RUESS Martin School of Aeronautics Northwestern Polytechnical University Qian Xuesen Laboratory of Space Technology China Aerospace Science and Technology Corporation Faculty of Aerospace Engineering Delft University of Technology

A knock-down factor is commonly used to take into account the obvious decline of the buckling load in a cylindrical shell caused by the inevitable imperfections. In 1968, NASA guideline SP-8007 gave knock-down factors which rely on a lower-bound curve taken from experimental data. Recent research has indicated that the NASA knock-down factors are inclined to produce very conservative estimations for the buckling load of imperfect shells, due to the limitations of the computational power and the experimental skills available five decades ago. A novel knock-down factor is proposed composed of two parts for the metallic stiffened cylinders. A deterministic study is applied to achieve the first part of the knock-down factor considering the measured geometric imperfection, the other types of imperfections are considered in the second part using a stochastic analysis. A smeared model is used to achieve the implementation of the measured geometric imperfection for the stiffened cylinder. This new robust and less conservative design for the stiffened cylinders is validated by using test results.

关键词： cylinders buckling conservative shells stochastic inevitable validated imperfect deterministic metallic

Inductively Coupled Plasma(ICP) Mass Spectrometry(MS) Hyphenated with Atomic Emission Spectrometry(AES) for Simultaneous Determination of Major, Minor and Micro Amounts of Elements in Geochemical Samples

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Chemical Research in Chinese Universities 2005年第6期21卷 753-756页

作者： huANG Zhen-yu ZHANG qin hu ke WU Jian-ling YANG Peng-yuan Department of Chemistry Fudan University Shanghai 200433 P. R. China Academy of Chinese Geology Science Langfang 065000 P. R. China Lab Tech Beijing 101312 P. R. China Institute of Chemistry and Chemical Engineering Guangxi University Nanning 530004 P. R. China

Introduction Geological resource survey demands for determining various constituents including major, minor, micro, trace and ultra-trace levels of elements for preparing the map of resource distribution of our country. As a powerful and popularly used technique for multi-element analysis, inductively coupled plasma（ICP） atomic emission spectrometry （AES） has been applied to this field for a period of time. However, ICP spectrometric determination of those micro, trace and ultratrace elements needs enrichment procedures for improving the detection limit, which is unacceptable in case a great mass of samples should be analyzed as that in the task of geological resource survey. On the other hand, although ICP mass spectrometry （MS） is considered the most powerful method for trace elements determination, it is difficult for ICP-MS to be used to determine the trace and major analytes simultaneously in a spectrum.

关键词： ICP-MS ICP-AES Hyphenated method Geochemistry sample

A new composite material produced by semi-continuous casting

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Acta Metallurgica Sinica(English Letters) 2010年第4期23卷 255-260页

作者： huixue JIANG ke qin Haitao ZHANG Jianzhong CUI key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University Shenyang 110819 China

A new composite material consisting of lxxx aluminum alloy and 7xxx aluminum alloy was produced by semi-continuous casting. Macrostructure, microstructure, composition distribution and hardness distribution of composite interface were analyzed. Macrostructure shows that composite interface is planar and clean with little evidence of porosity; microstructure shows that composite interface is a kind of metallurgical bonding; composition and hardness distributions have a good corresponding relationship. At the same time, the mechanical property of composite interface was measured, the tensile strength is 71 MPa, the shearing strength is 62 MPa and the bending strength is 142.5 MPa, which can also show that composite interface is a kind of metallurgical bonding. Temperature distribution of composite interface was obtained by measuring temperatures near composite interface in lxxx aluminum alloy.

关键词： Composite material lxxx aluminum alloy 7xxx aluminum alloy Semi-continuous casting

The axisymmetric long-wave interfacial stability of core-annular flow of power-law fluid with surfactant

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Acta Mechanica Sinica 2012年第1期28卷 24-33页

作者： Xue-Wei Sun Jie Peng ke-qin Zhu Department of Engineering Mechanics Tsinghua University100084 BeijingChina

The long wave stability of core-annular flow of power-law fluids with an axial pressure gradient is investigated at low Reynolds number. The interface between the two fluids is populated with an insoluble surfactant. The analytic solution for the growth rate of perturbation is obtained with long wave approximation. We are mainly concerned with the effects of shear-thinning/thickening property and interfacial surfactant on the flow stability. The results show that the influence of shear-thinning/thickening property accounts to the change of the capillary number. For a clean interface, the shear-thinning property enhances the capillary instability when the interface is close to the pipe wall. The converse is true when the interface is close to the pipe centerline. For shear-thickening fluids, the situation is reversed. When the interface is close to the pipe centerline, the capillary instability can be restrained due to the influence of surfactant. A parameter set can be found under which the flow is linearly stable.

关键词： Core-annular flow. Power-law fluid. Interfacial surfactant Long-wave stability

A comparative study for the impact performance of shaped charge JET on UHPC targets

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Defence Technology（防务技术） 2019年第4期15卷 506-518页

作者： Hao Wu Feng hu qin Fang Research Institute of Structural Engineering and Disaster Reduction College of Civil Engineering Tongji University Shanghai 200092 China key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education Tongji University Shanghai 200092 China Research Institute for National Defense Engineering of Academy of Military Sciences PLA Beijing 100091 China Amy Engineering University of PLA Nanjing 210007 China

With the development of two-stage munitions(a precursor shaped charge(SC)and a following kinetic energy projectile)to attack the hard concrete targets,as well as the increasing applications of ultra-high performance concrete(UHPC)in both civil and military protective structures,a comparative study on the impact performance of SC formed jet on UHPC target is performed experimentally and numerically at ***,a series of jet penetration/perforation test on the UHPC,45# steel and UHPC/45# steel composite targets are *** assessing the penetration depth and borehole(crater and tunnel)diameter,the influences of target material and configuration as well as the standoff distance of SC on the impact performance of jet are experimentally ***,by adopting the 2 D multi-material Arbitrary Lagrange-Euler(ALE)algorithm,Fluid-Structure Interaction(FSI)method and erosion algorithm implemented in the finite element code LS-DYNA,the formation and impact performance of jet in the present test are well ***,based on the validated numerical algorithms,constitutive models and the corresponding parameters,the influences of target material(UHPC,NSC and 45# steel),standoff distance,target configuration(stacked and spaced)and weight efficiency on the impact performance of jet are further *** derived conclusions could provide helpful references for evaluating the ballistic performance of jet and designing the protective structures.

关键词： Shaped charge jet Ultra-high performance concrete Penetration Perforation Numerical simulation

Influence of homodyne-based feedback control on the entropic uncertainty in open quantum system

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Chinese Physics B 2019年第7期28卷 137-143页

作者： Juju hu qin Xue College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China key Laboratory of Photoelectronics and Telecommunication of Jiangxi Province Nanchang 330022 China

For an open quantum system containing two qubits under homodyne-based feedback control, we investigate the dynamical behaviors of quantum-memory-assisted entropic ***, we analyze the influence of feedback modes and coefficients on the entropic *** investigations show that the memory qubit should be placed in a non-dissipative channel if the single dissipative channel condition can be chosen, which helps reduce the entropic uncertainty of the *** the homodyne feedback control F =λσx(or F =λσy), due to different roles of the entangled qubits A and B, when they are subject to feedback control with different feedback coefficients λ, the exchange of feedback coefficients will cause variations of the entropic *** the feedback coefficient corresponding to the memory qubit B is larger(λB >λA), the steady value of the entropic uncertainty will be small, which is conducive to enhancing the robustness of the ***, for the feedback control F =λσz, the difference between the feedback coefficients has no effect on the steady values of the entropic uncertainty.

关键词： homodyne-based feedback control quantum-memory-assisted entropic uncertainties memory qubit open quantum system

Yield criterions of metal plasticity in different stress states

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Acta Metallurgica Sinica(English Letters) 2009年第2期22卷 123-130页

作者： Fengping YANG qin SUN Wei hu School of Aeronautics Northwestern Polytechnical University Xitan 710072 China Institute of Orthopedic Oncology Tangdu Hospital Fourth Military Medical University Xi＇an 710038 China

Five types of tensile tests were conducted to study the yield .behavior of 2A12-T4 aluminum alloy. Parallel finite element models were built for each test and solved with ABAQUS with different yield criterions. The result shows that any of the four criterions： von Mises yield criterion, Tresca criterion, Twin-Shear criterion and yon Mises criterion with hydrostatic pressure correction, overestimates the yield strengths of the specimens. Rather than hydrostatic pressure, Lode stress parameter is the key factor that affects the differences between experimental and simulation results. Based on this concept, a new yield model with Lode dependence modified from yon Mises criterion is postulated. Although one more parameter needs to be confirmed, the simulation results of this yield model are better than those of other criterions.

关键词： Yield strength Lode stress parameter Hydrostatic pressure Finite element method (FEM)

Electronic physics and possible superconductivity in layered orthorhombic cobalt oxychalcogenides

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Science Bulletin 2017年第8期62卷 563-571页

作者： Congcong Le Shengshan qin Jiangping hu Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China Kavli Institute of Theoretical Sciences University of Chinese Academy of Sciences Beijing 100049 China

We suggest that cobalt-oxychalcogenide layers constructed by vertex sharing CoA_2O_2(A = S, Se, Te) tetrahedra, such as BaCoAO, are strongly correlated multi-orbitals electron systems that can provide important clues on the cause of unconventional superconductivity. Differing from cuprates and iron-based superconductors, these systems lack of the D_(4h) symmetry classification. However, their parental compounds possess antiferromagnetic(AFM) Mott insulating states through pure superexchange interactions and the low energy physics near Fermi surfaces upon doping is mainly attributed to the three t_(2g) orbitals that dominate the AFM interactions. We derive a low energy effective model for these systems and predict that a d-wave-like superconducting state with reasonable high transition temperature can emerge by suppressing the AFM ordering even if the pairing symmetry can not be classified by the rotational symmetry any more.

关键词： Superconductivity Transition metal bichalcogenides High temperature superconductors Anti ferromagnetism