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321.
When two-dimensional electrons are subjected to a very strong magnetic field, they are believed to form a triangular crystal. By a direct comparison with the exact wave function, we demonstrate that this crystal is not a simple Hartree-Fock crystal of electrons but an inherently quantum mechanical crystal characterized by a nonperturbative binding of quantized vortices to electrons. It is suggested that this has qualitative consequences for experiment. 相似文献
322.
For 0<p,α<∞, let ‖f‖p,α be the Lp-norm with respect the weighted measure . We define the weighted Bergman space Aαp(D) consisting of holomorphic functions f with ‖f‖p,α<∞. For any σ>0, let A−σ(D) be the space consisting of holomorphic functions f in D with . If D has C2 boundary, then we have the embedding Aαp(D)⊂A−(n+α)/p(D). We show that the condition of C2-smoothness of the boundary of D is necessary by giving a counter-example of a convex domain with C1,λ-smooth boundary for 0<λ<1 which does not satisfy the embedding. 相似文献
323.
利用NaOH碱式消化快脉冲雾化原子吸收法测定培养细胞内的K,… 总被引:2,自引:0,他引:2
用6%的NaOH碱式消化培养细胞,取50μl消化液,用考马斯亮蓝法测定蛋白含量,共余用La-EDTA等量稀后,采用自制微量进样装置,运用快脉冲雾化技术,使进样体积最低降至20μl在日立180-80型原子吸收分光光度计上测定K,Ca和Mg含量,结果以每克蛋白含量表示。 相似文献
324.
Raj Kishore Sharma Gurmeet Singh Yong Gun Shul Hansung Kim 《Physica B: Condensed Matter》2007,390(1-2):314-319
Mechanistic studies on the electrocrystallization of manganese telluride (MnTe) thin film are reported using aqueous acidic solution containing MnSO4 and TeO2. Tartaric acid was used for the inhibition of hydrated manganese oxide anodic growth at counter electrode. A detailed study on the mechanistic aspect of electrochemical growth of MnTe using cyclic voltametry is carried out. Conditions for electrochemical growth of manganese mono and di telluride thin films have been reported using cyclic voltammetric scans for Mn2+, Te4+ and combined Mn2+ and Te4+. X-ray diffraction showed the formation of polycrystalline MnTe films with cubic, hexagonal and orthorhombic mixed phases. MnTe film morphology was studied using scanning electron microscope. Susceptibility and electrical characterization supports the anti-ferromagnetic behavior of the as-deposited MnTe thin film. 相似文献
325.
A tripodal receptor R1 with a combination of nitrogen and oxygen-based binding sites was designed and used for the selective determination of Cu2+. The fluorescence emission profile of R1 in the presence of Cu2+ showed a marked enhancement in fluorescence intensity, indicating high selectivity among other metal ions. The R1–Cu2+ complex was further explored as a sensor for anion detection. Upon addition of Br?, switching to a fluorescence “off” state was observed. The Br? selectivity of the complex over a wide range of concentrations was observed via titrimetric analysis through changes in the emission spectra. 相似文献
326.
Doo Gun Kim Tae-Kyeong Lee Hyun Chul Ki Hwe Jong Kim Nadir Dagli 《Optics Communications》2011,284(19):4473-4476
The direct intensity modulation of a three-guide coupled rectangular ring laser having bidirectional lasing characteristics is reported for the first time. The rectangular laser cavity consists of four low loss total internal reflection mirrors and an output coupler made out of three passive coupled waveguides. The laser is fabricated using a total cavity length of 580 μm with active section lengths of 250 μm. For both the clockwise and counterclockwise circulating directions, a lasing threshold of around 38 mA is obtained at room temperature under continuous wave operation. A maximum 3-dB modulation bandwidth of approximately 3.2 GHz is observed in both circulating directions. 相似文献
327.
Yang HS Shin J Bhang SH Shin JY Park J Im GI Kim CS Kim BS 《Experimental & molecular medicine》2011,43(11):622-629
Platelet-rich plasma (PRP) contains growth factors that promote tissue regeneration. Previously, we showed that heparin-conjugated fibrin (HCF) exerts the sustained release of growth factors with affinity for heparin. Here, we hypothesize that treatment of skin wound with a mixture of PRP and HCF exerts sustained release of several growth factors contained in PRP and promotes skin wound healing. The release of fibroblast growth factor 2, platelet-derived growth factor-BB, and vascular endothelial growth factor contained in PRP from HCF was sustained for a longer period than those from PRP, calcium-activated PRP (C-PRP), or a mixture of fibrin and PRP (F-PRP). Treatment of full-thickness skin wounds in mice with HCF-PRP resulted in much faster wound closure as well as dermal and epidermal regeneration at day 12 compared to treatment with either C-PRP or F-PRP. Enhanced skin regeneration observed in HCF-PRP group may have been at least partially due to enhanced angiogenesis in the wound beds. Therefore, this method could be useful for skin wound treatment. 相似文献
328.
Wail Al Zoubi Abbas Ali Salih Al‐Hamdani Susan Duraid Ahmed Young Gun Ko 《Journal of Physical Organic Chemistry》2018,31(2)
The new Schiff base 1‐[(2‐{1‐[(dicyclohexylamino)‐methyl]‐1H‐indol‐3‐yl}‐ethylimino)‐methyl]naphthalen‐2‐ol (HL) was prepared from 1‐{[2‐(1H‐Indol‐3‐yl)‐ethylimino] methyl}‐naphthalen‐2‐ol and dicyclohexyl amine. From this Schiff base, monomeric complexes [M (L)n (H2O)2 Cl2] with M = Cr, Fe, Mn, Cd, and Hg were synthesized and characterized based on elemental analysis (EA), FT‐IR, mass(MS), UV‐visible, thermal analysis, magnetic moment, and molar conductance. The results showed that the geometrical structural were octahedral geometries for the Cr(III) and Fe(III) complexes, square planer for Pd(II) complex, and tetrahedral for Mn(II), Cd(II), and Hg(II) complexes. Kinetic parameters such as ΔE*,ΔH*, ΔG*, and K of the thermal decomposition stages were calculated from the TGA curves using Coats‐Redfern method. Additionally, density functional theory (DFT) was applied for calculations of both electronic structure and spectroscopic properties of synthesized Schiff base and its complexes. The analysis of electrostatic potential (EPS) maps correlates well with the computed energies providing on the dominant electrostatic nature of N‐H‐‐‐O interactions. The biological activities had been tested in vitro against Staphylococcus aureus, Pseudomonas aeruginosa, as well fungi like Penicillium expansum, Fusarium graminearum, Macrophomina phasealina, and Candida albicans bacteria in order to assess their antimicrobial potential. 相似文献
329.
Jun-Yeong Yoon Yangjin Lee Dong-Gyu Kim Dong Gun Oh Jin Kyun Kim Linshuo Guo Jungcheol Kim Jeongheon Choe Kihyun Lee Hyeonsik Cheong Chae Un Kim Young Jai Choi Yanhang Ma Kwanpyo Kim 《Angewandte Chemie (International ed. in English)》2023,62(36):e202307102
Elemental phosphorus exhibits fascinating structural varieties and versatile properties. The unique nature of phosphorus bonds can lead to the formation of extremely complex structures, and detailed structural information on some phosphorus polymorphs is yet to be investigated. In this study, we investigated an unidentified crystalline phase of phosphorus, type-II red phosphorus (RP), by combining state-of-the-art structural characterization techniques. Electron diffraction tomography, atomic-resolution scanning transmission electron microscopy (STEM), powder X-ray diffraction, and Raman spectroscopy were concurrently used to elucidate the hidden structural motifs and their packing in type-II RP. Electron diffraction tomography, performed using individual crystalline nanowires, was used to identify a triclinic unit cell with volume of 5330 Å3, which is the largest unit cell for elemental phosphorus crystals up to now and contains approximately 250 phosphorus atoms. Atomic-resolution STEM imaging, which was performed along different crystal-zone axes, confirmed that the twisted wavy tubular motif is the basic building block of type-II RP. Our study discovered and presented a new variation of building blocks in phosphorus, and it provides insights to clarify the complexities observed in phosphorus as well as other relevant systems. 相似文献
330.
Kleperis Jānis Bajārs Gunārs Grīnberga Līga Vaivars Guntars Purāns Juris Vītiņš Ģirts Kučinskis Gints 《Journal of Solid State Electrochemistry》2023,27(7):1641-1660
Journal of Solid State Electrochemistry - Solid state ionics is one of the key research topics of the Institute of Solid State Physics, University of Latvia since its establishment. The research... 相似文献