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We present a robust filter SQP algorithm for solving constrained optimization problems. This algorithm is based on the modified quadratic programming proposed by Burke to avoid the infeasibility of the quadratic programming subproblem at each iteration. Compared with other filter SQP algorithms, our algorithm does not require any restoration phase procedure which may spend a large amount of computation. The main advantage of our algorithm is that it is globally convergent without requiring strong constraint qualifications, such as Mangasarian–Fromovitz constraint qualification (MFCQ) and the constant rank constraint qualification (CRCQ). Furthermore, the feasible limit points of the sequence generated by our algorithm are proven to be the KKT points if some weaker conditions are satisfied. Numerical results are also presented to show the efficiency of the algorithm. 相似文献
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Jianping Wang Jian Zhang Kun Miao Hongying Yun Hong C. Shen Weili Zhao Chungen Liang 《Tetrahedron letters》2017,58(4):333-337
NH-sulfoximines can be prepared efficiently from corresponding sulfoxides in the presence of sodium azide and Eaton’s reagent. This metal-free and efficient methodology is applicable to a wide variety of functionalized sulfoxides to afford NH-sulfoximines in good to excellent yields with shorter reaction time than previously reported methods. 相似文献
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Low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O nanopowders(NPs)would determine their practical application in purifying wastewater.In this contribution,ZnO NPs were scalably synthesized via the simple reaction of Zn powder with H_2O vapor in autoclave.The structural,morphological and optical properties of the samples were systematically characterized by X-ray diffraction,scanning electron microscopy,Fourier transform infrared spectra,transmission electron microscopy,Micro-Raman,photoluminescence,and ultraviolet-visible spectroscopy.The as-prepared Zn O NPs are composed of nanoparticles with 100–150 nm in diameter,and have a small Brunauer-Emmett-Teller surface area of 6.85 m~2/g.The formation of Zn O nanoparticles is relative to the peeling of H_2 release.Furthermore,the product has big strain-stress leading to the red-shift in the band gap of product,and shows a strong green emission centered at 515 nm revealing enough atomic defects in Zn O NPs.As a comparison with P25,the obtained dust gray Zn O NPs have a strong absorbance in the region of 200–700 nm,suggesting the wide wave-band utilization in sunlight.Based on the traits above,the Zn O NPs show excellent photocatalytic activity on the degradation of rhodamine B(Rh-B)under solar light irradiation,close to that under UV irradiation.Importantly,the Zn O NPs could be well recycled in water due to the quick sedimentation in themselves in solution.The low-cost and scalable preparation,high photocatalytic activity,and convenient recycle of Zn O NPs endow themselves with promising application in purifying wastewater. 相似文献
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[reaction: see text] A metal-catalyzed tandem 1,4-addition/cyclization between propargyl alcohol and a Michael acceptor, such as alkylidene malonate, has been developed. In the presence of catalytic amounts of zinc triflate [Zn(OTf)(2)] and triethylamine (Et(3)N), various 2-alkylidene-1,3-dicarbonyl compounds reacted with propargyl alcohol to give 3- or 4-methylene tetrahydrofurans in excellent yields. 相似文献
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In this paper, we suggest a simple representation for notation of Kekulé valence bond (KVB) structures and longer range resonance valence bond (RVB) structures, which is called "the adjacency bonding array". In this representation, only an N component one-dimensional array is needed for inscribing each KVB or longer range RVB structure for an N-carbon system. Based on the adjacency bonding arrays, we develop very efficient algorithms for the systematic search of KVB and RVB structures as well as evaluation of the basis set overlap and Hamiltonian matrices. 相似文献
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In this paper, the authors study the existence of nontrivial solutions for the Hamiltonian systems z(t) = JH(t,z(t)) with Lagrangian boundary conditions, where H(t,z)=1/2((B)(t)z,z) (H)(t,z),(B)(t) is a semipositive symmetric continuous matrix and (H) satisfies a superquadratic condition at infinity. We also obtain a result about the L-index. 相似文献
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通过简化、优化现有的SD大鼠睾丸支持细胞分离纯化方法,获得高纯度大量的支持细胞。选用15d的雄性SD大鼠,处死取出睾丸,采用0.25%胰蛋白酶消化的一步消化法分离支持细胞,置于35℃、5%CO2和100%湿度空气的CO2培养箱中进行培养。24h后用20mmol·L-1的Tris-HCl处理细胞,并用油红O、HE染色和Feulgen染色观察对培养的支持细胞进行鉴定。分离纯化的支持细胞纯度达到90%以上,纯化获得的细胞其形体结构与支持细胞一致。因此,一步消化法可以获得高纯度的支持细胞。 相似文献