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排序方式: 共有2205条查询结果,搜索用时 312 毫秒
931.
Alexopoulos T Allen C Anderson EW Areti H Banerjee S Beery PD Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y De Bonte R Erwin A Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Kenney VP Koltick D Lindsey CS LoSecco JM McMahon T McManus AP Morgan N Nelson K Oh SH Piekarz J Porile NT Reeves D Scharenberg RP Stringfellow BC Stampke SR Thompson M Turkot F Walker WD Wang CH Wesson DK 《Physical review letters》1988,60(16):1622-1625
932.
Critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS), an anionic surfactant, has been investigated in aqueous solutions of a variety of room temperature ionic liquids (RTILs): 1,3-dimethylimidazolium iodide (Me2IM-I, 2), 1-butyl-3-methylimidazolium chloride (BMIM-Cl, 3), 1-hexyl-3-methylimidazolium chloride (HxMIM-Cl, 4), 1-methyl-3-octylimidazolium chloride (MOIM-Cl), 5, and 1-methyl-3-octylimidazolium tetrafluoroborate (MOIM-BF4, 6). The CMC of SDS is shown to correlate with the nature of the alkyl groups in the RTILs; SDS showed appreciably higher CMCs in presence of ionic liquids 2 and 3, whereas in the presence of ionic liquids 4, 5, and 6 much smaller CMCs were observed. The nature of the gigenions, Cl- or BF4-, has no noticeable effect on the observed CMC values. 相似文献
933.
Seok-Jin Kang Masaki Kashiwara Myungho Kim Se-Jin Oh 《Selecta Mathematica, New Series》2016,22(4):1987-2015
Let \(U'_q(\mathfrak {g})\) be a twisted affine quantum group of type \(A_{N}^{(2)}\) or \(D_{N}^{(2)}\) and let \(\mathfrak {g}_{0}\) be the finite-dimensional simple Lie algebra of type \(A_{N}\) or \(D_{N}\). For a Dynkin quiver of type \(\mathfrak {g}_{0}\), we define a full subcategory \({\mathcal C}_{Q}^{(2)}\) of the category of finite-dimensional integrable \(U'_q(\mathfrak {g})\)-modules, a twisted version of the category \({\mathcal C}^{(1)}_{Q}\) introduced by Hernandez and Leclerc. Applying the general scheme of affine Schur–Weyl duality, we construct an exact faithful KLR-type duality functor \({\mathcal F}_{Q}^{(2)}:\mathrm{Rep}(R) \rightarrow {\mathcal C}_{Q}^{(2)}\), where \(\mathrm{Rep}(R)\) is the category of finite-dimensional modules over the quiver Hecke algebra R of type \(\mathfrak {g}_{0}\) with nilpotent actions of the generators \(x_k\). We show that \({\mathcal F}_{Q}^{(2)}\) sends any simple object to a simple object and induces a ring isomorphism Open image in new window . 相似文献
934.
This article considers a new type of principal component analysis (PCA) that adaptively reflects the information of data. The ordinary PCA is useful for dimension reduction and identifying important features of multivariate data. However, it uses the second moment of data only, and consequently, it is not efficient for analyzing real observations in the case that these are skewed or asymmetric data. To extend the scope of PCA to non-Gaussian distributed data that cannot be well represented by the second moment, a new approach for PCA is proposed. The core of the methodology is to use a composite asymmetric Huber function defined as a weighted linear combination of modified Huber loss functions, which replaces the conventional square loss function. A practical algorithm to implement the data-adaptive PCA is discussed. Results from numerical studies including simulation study and real data analysis demonstrate the promising empirical properties of the proposed approach. Supplementary materials for this article are available online. 相似文献
935.
Spontaneous Formation of an Air‐Stable Radical upon the Direct Fusion of Diphenylmethane to a Triarylporphyrin 下载免费PDF全文
Kenichi Kato Wonhee Cha Juwon Oh Prof. Dr. Ko Furukawa Prof. Dr. Hideki Yorimitsu Prof. Dr. Dongho Kim Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2016,55(30):8711-8714
The direct fusion of a diphenylmethane segment to a NiII 5,10,15‐triarylporphyrin with three linkages furnished an air‐ and moisture‐stable neutral radical through unexpected and spontaneous oxidation. This radical was demetalated by treatment with H2SO4 and CF3CO2H to provide the corresponding free‐base radical. These porphyrin radicals are very stable owing to spin delocalization and have been fully characterized through UV/Vis/NIR absorption spectroscopy, X‐ray crystallographic analysis, magnetic susceptibility measurements, electrochemical studies, laser‐based ultrafast spectroscopic studies, and theoretical calculations. They were chemically oxidized and reduced to the corresponding cation and anion but did not react with hydrogen‐atom donors. 相似文献
936.
Back Cover: Aromaticity Reversal in the Lowest Excited Triplet State of Archetypical Möbius Heteroannulenic Systems (Angew. Chem. Int. Ed. 22/2016) 下载免费PDF全文
937.
This study attempted to control the radiated exterior noise from a rectangular enclosure in which an internal plate vibrates by acoustic excitation and noise is thus radiated from that plate. Multi-channel active control was applied to reduce the vibration and external radiation of this enclosed plate. A piezoelectric ceramic was used as a distributed actuator for multiple mode control of the vibration and radiated noise in the acoustically excited plate. To maximize the effective control, an approach was proposed for attachment the piezoelectric actuator in the optimal location. The plate and internal acoustic space in the enclosure are coupled with each other. This will change dominant frequency characteristics of the plate and, thus, those of the externally radiated noise. Active noise control was accomplished using an accelerometer attached to the plate and a microphone placed adjacent to that plate as an error sensor under acoustic excitation of sine wave and white noise. It was found that the control of radiated external radiation noise requires a microphone as an error sensor, a sound pressure sensor due to vibration of the plate, differences in the dominant frequency of externally radiated noise, and complex vibration modes of the plate. 相似文献
938.
939.
Electrochemistry of Layered Graphitic Carbon Nitride Synthesised from Various Precursors: Searching for Catalytic Effects 下载免费PDF全文
Ying Teng Yew Chee Shan Lim Alex Yong Sheng Eng Junghoon Oh Prof. Sungjin Park Prof. Martin Pumera 《Chemphyschem》2016,17(4):481-488
Graphitic carbon nitride (g‐C3N4), synthesised by pyrolysis of different precursors (dicyandiamide, melamine and urea) under varying reaction conditions (air and nitrogen gas) is subjected to electrochemical studies for the elucidation of the inherent catalytic efficiency of the pristine material. Contrary to popular belief, pristine g‐C3N4 shows negligible, if any, enhancement in its electrochemical behaviour in this comprehensive study. Voltammetric analysis reveals g‐C3N4 to display similar catalytic efficiency to the unmodified glassy carbon electrode surface on which the bulk material was deposited. This highlights the non‐catalytic nature of the pristine material and challenges the feasibility of using g‐C3N4 as a heterogeneous catalyst to deliver numerous promised applications. 相似文献
940.
Back Cover: Biodegradable Inorganic Nanovector: Passive versus Active Tumor Targeting in siRNA Transportation (Angew. Chem. Int. Ed. 14/2016) 下载免费PDF全文