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排序方式: 共有549条查询结果,搜索用时 15 毫秒
1.
Hideaki Murasugi Dr. Shohei Kumagai Dr. Hiroaki Iguchi Prof. Dr. Masahiro Yamashita Dr. Shinya Takaishi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(42):9885-9891
Crystal structures of a series of organic–inorganic hybrid gold iodide perovskites, formulated as A2[AuII2][AuIIII4] [A=methylammonium (MA) ( 1 ) and formamidinium (FA) ( 2 )], A′2[I3]1−x[AuII2]x[AuIIII4] [A′=imidazolium (IMD) ( 3 ), guanidinium (GUA) ( 4 ), dimethylammonium (DMA) ( 5 ), pyridinium (PY) ( 6 ), and piperizinium (PIP) ( 7 )], systematically changed depending on the cation size. In addition, triiodide (I3−) ions were partly incorporated into the AuI2− sites of 3 – 7 , whereas they were not incorporated into those of 1 and 2 . Such a difference comes from the size of the organic cation. Optical absorption spectra showed characteristic intervalence charge-transfer bands from AuI to AuIII species, and the optical band gap increased as the size of the cation became larger. 相似文献
2.
Atsuo Kuniba Tomoki Nakanishi Zengo Tsuboi 《Communications in Mathematical Physics》2002,227(1):155-190
We study a class of systems of functional equations closely related to various kinds of integrable statistical and quantum
mechanical models. We call them the finite and infinite $Q$-systems according to the number of functions and equations. The
finite Q-systems appear as the thermal equilibrium conditions (the Sutherland–Wu equation) for certain statistical mechanical systems.
Some infinite Q-systems appear as the relations of the normalized characters of the KR modules of the Yangians and the quantum affine algebras.
We give two types of power series formulae for the unique solution (resp. the unique canonical solution) for a finite (resp.
infinite) Q-system. As an application, we reformulate the Kirillov–Reshetikhin conjecture on the multiplicities formula of the KR modules
in terms of the canonical solutions of Q-systems.
Received: 2 August 2001 / Accepted: 27 December 2001 相似文献
3.
Diamond-like carbon films prepared by pulsed-laser evaporation 总被引:1,自引:0,他引:1
T. Sato S. Furuno S. Iguchi M. Hanabusa 《Applied Physics A: Materials Science & Processing》1988,45(4):355-360
Diamond-like carbon thin films were prepared by pulsed-laser evaporation. In this method a carbon target was irradiated by a XeCl laser with a power density of 3×108 W/cm2 and carbon atoms, together with a small number of ions, were produced. Deposition rates and film properties changed sensitively with substrate temperature. The films deposited at 50°C were diamond-like, having reasonable hardness, high refractive index (2.1–2.2 at 633 nm), optical transparency in the infrared, electrical resistivity of 108 cm and chemical inertness (no dissolution in a HFHNO3 solution). The band gap measured from optical absorption was 1.4 eV. Raman spectrum and infrared absorption, whose features varied with the substrate temperature, were also measured. The films were amorphous and no crystallinity was observed, as confirmed by x-ray diffraction, transmission electron diffraction and Raman spectroscopy. Hydrogen atoms were incorporated in the films with a typical H/C ratio of 0.3. The application of a negative bias to the substrate modified the deposition due to the presence of ions. 相似文献
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Yuko Ouchi Yasuhiro Morisaki Dr. Tomoki Ogoshi Dr. Yoshiki Chujo Prof. Dr. 《化学:亚洲杂志》2007,2(3):397-402
A reaction of the P‐chiral compound (S,S)‐1,2‐bis(boranato(tert‐butyl)methylphosphino)ethane with an azobenzene derivative gave stimuli‐responsive polymers with P‐chiral phosphines in the main chain. This is the first example of a stimuli‐responsive P‐chiral polymer. The polymer isomerized from the trans to the cis form upon UV irradiation and reverted to the trans form reversibly. The polymer was able to coordinate to platinum, and the resulting polymer complex exhibited the Cotton effect owing to the chirality of the phosphorus atoms. The structure of the P‐chiral polymer obtained could be changed reversibly by light and thermal stimuli, and the polymer chain was induced to rotate helically when complexed with transition metals through the chiral phosphorus atoms. 相似文献
10.
Desialylated fetuin (asialofetuin) was adopted as a carrier for introducing drugs in parenchymal liver cells. Mitomycin C, as a model guest-compound, was covalently attached to asialofetuin through a spacer of the succinyl group. The asialofetuin-mitomycin C conjugate contained 4.4 w/w% of mitomycin C and liberated it gradually at physiological conditions (t1/2 = 37 h). The survival time of the conjugate in rat blood circulation was significantly smaller than that of the non-desialylated fetuin conjugate; the elimination half-life was 7.3 min after intravenous injection. At 30 min after injection of the conjugate in rats, 40% of the dose was present in the liver. Parenchymal cells in the liver selectively took up the conjugate, which was highly distributed to the lysosomal fraction in the cell. The greater uptake of the conjugate by hepatocytes reflected the increased excretion in the bile; totally 10.4% of the dose was recovered. 相似文献