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111.
In batch statistical process control (BSPC), data from a number of “good” batches are used to model the evolution (trajectory) of the process and they also define model control limits, against which new batches may be compared. The benchmark methods used in BSPC include partial least squares (PLS) and principal component analysis (PCA). 相似文献
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Mehran Asad Ayoubi Kaizheng Zhu Bo Nyström Ulf Olsson Kristoffer Almdal Alexei R. Khokhlov Lennart Piculell 《Journal of Polymer Science.Polymer Physics》2013,51(23):1657-1671
Samples of compositionally (highly) asymmetric diblock copolymers and, also, mixtures of diblock and triblock copolymers (the latter obtained as end‐coupling products of two diblock molecules of the mixture), composed of (a) monodisperse majority block(s) of poly(styrene) (PS) and a polydisperse minority block of poly(methacrylic acid) (PMAA), microphase separate into spherical PMAA microdomains, either in disordered liquid‐like state or body‐centered‐cubic (BCC) arrangement, at various annealing temperatures T, in the strong segregation regime SSR. We found that (i) the microphase separated state is favored over an anticipated molecularly homogenous state, (ii) the spherical microdomain morphology (with BCC symmetry) is favored over an anticipated hexagonally packed cylindrical morphology, (iii) the extent of the dissolution of short PMAA blocks in the PS material can be quantified, (iv) the spherical microdomains are dilated, and (v) despite molecular‐weight (and architectural) polydispersity, well‐ordered BCC structures can be obtained. © 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2013 , 51, 1657–1671 相似文献
114.
Krister Thuresson Lennart Piculell Björn Lindman 《Journal of Dispersion Science and Technology》2013,34(1-2):663-676
A quick and convenient route to prepare a highly viscoelastic mixture of two oppositely charged polyelectrolytes is presented. The investigation was essentially performed at a fixed total polyelectrolyte concentration. The phase behaviour was studied at varying ratios between the two oppositely charged polyions. The mixtures phase separated associatively at mixing ratios in the vicinity of overall charge neutrality, while by screening the attractive forces with NaCl the precipitate could be dissolved. At certain mixing ratios off charge neutrality the mixtures were highly viscoelastic single-phase solutions in the absence of screening electrolyte. When NaCl was added to such a solution the viscoelasticity decreased strongly since the attractive forces between the oppositely charged polyions were screened. Therefore, by contacting an initially salt free mixture of polyions with a brine solution of known concentration, the diffusion of salt into the polyion matrices could be monitored by following the rheology of the mixture as a function of the contact time. It is shown that the transport of NaCl inside the polyion matrices was diffusion controlled. 相似文献
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Jordon-Thaden B Kreckel H Golser R Schwalm D Berg MH Buhr H Gnaser H Grieser M Heber O Lange M Novotný O Novotny S Pedersen HB Petrignani A Repnow R Rubinstein H Shafir D Wolf A Zajfman D 《Physical review letters》2011,107(19):193003
We present the results of a Coulomb explosion experiment that allows for the imaging of the rovibrational wave function of the metastable H2- ion. Our measurements confirm the predicted large internuclear separation of 6 a.u., and they show that the ion decays by autodetachment rather than by spontaneous dissociation. Imaging of the resulting H2 products reveals a large angular momentum of J = 25 ± 2, quantifying the rotation that leads to the metastability of this most fundamental molecular anion. 相似文献
117.
Lykke L Rodríguez-Escrich C Jørgensen KA 《Journal of the American Chemical Society》2011,133(38):14932-14935
The first catalytic enantioselective synthesis of oxaziridines is presented. The oxidation of aryl and alkyl aldimines with m-CPBA under organocatalytic conditions using cinchona alkaloid-derived catalysts furnished optically active oxaziridines in good yields and high enantioselectivities (up to 94% ee). Mechanistic investigations indicate a stepwise enantioselective oxidation process. 相似文献
118.
Kamali Saeed Häggström Lennart Ronneteg Sabina Berger Rolf 《Hyperfine Interactions》2004,156(1-4):315-319
Hyperfine Interactions - The quasi two-dimensional antiferromagnetic compound TlCo2Se2 has been studied by 57Fe Mössbauer spectroscopy. Small single crystals have been made with 2% Fe doping.... 相似文献
119.
Lars-Oloe Wahlund Jrgen Boethius Eva Kindstrand Olle Marions Jan Sf Lennart Wetterberg 《Magnetic resonance imaging》1989,7(6):599-603
Low grade gliomas were studied with ultra low field magnetic resonance imaging (ULF MRI). The tumors exhibited high tissue contrast in both T1 and T2-weighted images as compared to normal brain tissue. Moreover they were sharply delineated towards the surrounding brain tissue. When compared with X-ray computed tomography the tumors were more readily detected and delineated by using ultra-low field magnetic imaging. A computerassisted classification procedure was used to define new regions of interest for relaxation time estimation. By using this procedure more accurate estimations of the T1 and T2 values were obtained. 相似文献
120.