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101.
Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed. 相似文献
102.
Nguyen Thi Thu Huong Nguyen Chinh Cuong Ha Huy Bang Dao Thi Le Thuy 《International Journal of Theoretical Physics》2010,49(7):1457-1464
We study the pair production of scalar quark in a muon collider within the MSSM with CP violation. We show that including the CP phases can strongly affect the cross section of the process: \(\mu^{+}\mu^{-}\rightarrow \tilde{q}_{i}\bar{\tilde{q}}_{j}\). This could have an important impact on the search for squarks and the determination of the MSSM parameters at future colliders. 相似文献
103.
104.
105.
Assessing the goodness-of-fit (GOF) for intricate parametric spatial point process models is important for many application fields. When the probability density of the statistic of the GOF test is intractable, a commonly used procedure is the Monte Carlo GOF test. Additionally, if the data comprise a single dataset, a popular version of the test plugs a parameter estimate in the hypothesized parametric model to generate data for the Monte Carlo GOF test. In this case, the test is invalid because the resulting empirical level does not reach the nominal level. In this article, we propose a method consisting of nested Monte Carlo simulations which has the following advantages: the bias of the resulting empirical level of the test is eliminated, hence the empirical levels can always reach the nominal level, and information about inhomogeneity of the data can be provided. We theoretically justify our testing procedure using Taylor expansions and demonstrate that it is correctly sized through various simulation studies. In our first data application, we discover, in agreement with Illian et al., that Phlebocarya filifolia plants near Perth, Australia, can follow a homogeneous Poisson clustered process that provides insight into the propagation mechanism of these plants. In our second data application, we find, in contrast to Diggle, that a pairwise interaction model provides a good fit to the micro-anatomy data of amacrine cells designed for analyzing the developmental growth of immature retina cells in rabbits. This article has supplementary material online. 相似文献
106.
In the present paper, we give an investigation on the learning rate of l2-coefficient regularized classification with strong loss and the data dependent kernel functional spaces. The results show that the learning rate is influenced by the strong convexity. 相似文献
107.
In this paper, we give new upper bounds on the regularity of edge ideals whose resolutions are k-step linear; surprisingly, the bounds are logarithmic in the number of variables. We also give various bounds for the projective dimension of such ideals, generalizing other recent results. By Alexander duality, our results also apply to unmixed square-free monomial ideals of codimension two. We also discuss and connect these results to more classical topics in commutative algebra. 相似文献
108.
Abstract A new dinuclear hydrated nickel(II) tartrate has been isolated and structurally characterized by single-crystal X-ray diffraction.
The title compound formulated as [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 (C17H55.5Ni4O42.75) crystallizes in monoclinic system, space group P2(1)/c with a = 13.684(5), b = 17.143(6), c = 18.586(6) ?, β = 96.638(6)°, V = 4331(3) ?3, Z = 4. The unit cell contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference, half of menthol molecule and ten and a quarter packing water molecules. In each
dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way. Each Ni(II) atom is six-coordinated
by six O atoms from two tartrate units and two water molecules.
Index Abstract The crystal structure of complex [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference. In each dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way.
相似文献
109.
Zhe‐Chang He Soren K. Mellerup Lijie Liu Xiang Wang Caitlin Dao Suning Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6755-6759
B(npy)Ar2 (npy=2‐(naphthalen‐1‐yl)pyridine) compounds bearing various nonbulky aryl groups undergo a clean and sequential two‐step photoisomerization in which two aryl substituents on boron migrate to a carbon atom of the naphthyl moiety. The second isomerization step is the first example of a reversible photoisoermization between a borepin and a borirane. Both steric and electronic factors have been found to have a great impact on this photoreactivity. Furthermore, the borirane isomer reacts with oxygen, forming a rare oxaborepin dimer. 相似文献
110.
Dao Le Marco Dilger Vincent Pertici Silvia Diabat Didier Gigmes Carsten Weiss Guillaume Delaittre 《Angewandte Chemie (International ed. in English)》2019,58(14):4725-4731
We report the straightforward, time‐efficient synthesis of radical core–shell nanoparticles (NPs) by polymerization‐induced self‐assembly. A nitroxide‐containing hydrophilic macromolecular precursor was prepared by ring‐opening metathesis copolymerization of norbornenyl derivatives of TEMPO and oligoethylene glycol and was chain‐extended in situ with norbornene in ethanolic solution, leading to simultaneous amphiphilic block copolymer formation and self‐assembly. Without any intermediate purification from the monomers to the block copolymers, radical NPs with tunable diameters ranging from 10 to 110 nm are obtained within minutes at room temperature. The high activity of the radical NPs as chemoselective and homogeneous, yet readily recyclable catalysts is demonstrated through oxidation of a variety of alcohols and recovery by simple centrifugation. Furthermore, the NPs show biocompatibility and antioxidant activity in vitro. 相似文献