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101.
半群中的(λ,μ)-模糊理想(英文) 总被引:2,自引:1,他引:1
在半群中给出了(λ,μ)-模糊子半群和各种(λ,μ)-模糊理想的概念,讨讹了它们的一些性质,并给出了各种(λ,μ)-模糊理想的充分必要条件. 相似文献
102.
Jens Rumschöttel Susann Baus Sabine Kosmella Dietmar Appelhans 《Composite Interfaces》2018,25(1):1-11
Polyplexes between a double-stranded Salmon DNA and hyperbranched poly(ethyleneimine) (PEI) as well as a maltosylated PEI-Mal were incorporated into a gelatin/chitosan hydrogel scaffold. Calorimetric experiments of the polyplexes show a decrease of the melting temperature in presence of PEI and a peak splitting in presence of PEI-Mal, which can be interpreted to a partial compaction of the DNA strands in presence of PEI-Mal. When the polyplexes are incorporated into a gelatin/chitosan scaffold in the swollen state, the DNA melting peaks at 90 and 93 °C, respectively, indicate in both cases the release of the DNA at the surface of the hydrogel scaffold in a more compact form. Specific interactions between the PEI-Mal shell and gelatin are responsible for the tuning of the release properties in presence of the maltose units in the hyperbranched PEI. 相似文献
103.
Design and performance of a composite Tm:YAG laser pumped by VBG-stabilized narrow-band laser diode
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A 2-μm composite Tm:YAG laser pumped with a narrow-band laser diode was presented. The temperature distribution and thermal lens in the Tm:YAG were numerically simulated by a finite element method and the results were used to design the special cavity, in order to achieve a high efficiency and stable output. With a 25-W incident pump power, we obtained a maximum output power of 11 W at 2018.5 nm, corresponding to a slope efficiency of 51.3% and an optical-to-optical efficiency of 44.5%, respectively. The beam quality was measured to be M_x~2= 1.8 and M_y~2= 1.6. 相似文献
104.
采用高压射频等离子体增强化学气相沉积方法在非晶和微晶两种n型硅薄膜衬底上沉积了一系列不同厚度的本征微晶硅薄膜,研究了不同n型硅薄膜对本征微晶硅薄膜的表面形貌、晶化率和结晶取向等结构特性的影响.结果表明,本征微晶硅薄膜结构对n型掺杂层具有强烈的依赖作用,微晶n型掺杂层能够有效减少n/i界面非晶孵化层的厚度,改善本征微晶硅薄膜的纵向均匀性,进而提高微晶硅n-i-p太阳电池性能.
关键词:
孵化层
微晶硅薄膜
纵向均匀性
n-i-p太阳电池 相似文献
105.
106.
A new μ-chloro-bridged one-dimensional coordination polymer Cd(dmbpy)Cl2n(dmbpy=4,4′-dimethyl-2,2′-bipyridine) has been synthesized and structurally characterized by elemental analyses=IR=UV spectra and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic system=space group C2/c with a=17.745(4)=b=10.326(2)=c=7.3382(15)=β=106.85(3)o=V=1286.9(4)3=Z=4=C12H12N2Cl2Cd=Mr=367.54=Dc=1.897 g/cm3=F(000)=720=λ(MoKα)=0.71073=μ=2.089 mm-1=R=0.0368 and wR=0.1048 for 1041 observed reflections(I > 2σ(I)).Cadmium(II) adopts a distorted octahedral coordination geometry and adjacent coordination chains are intercalated in a zipper-like fashion into 2D layers through the π-π stacking interactions between dmbpy.Fluorescent 相似文献
107.
Emmanuel Zimmermman Moreira Luiz Alberto Beraldo de Moraes Marcos Nogueira Eberlin Yassuko Iamamoto Sofia Nikolaou 《Polyhedron》2008
The novel asymmetric metallo-organic triads cis- and trans-[B(4-py)BPFPH2{Ru3O(Ac)6(py)2}{Ru(bpy)2Cl}](PF6)2 (5a,b) for which cis- and trans-B(4-py)BPFPH2 = 5,10-bis(pentafluorophenyl)-15,20-bis(4-pyridyl)porphyrin and 5,15-bis(pentafluorophenyl)-10,20-bis(4-pyridyl)porphyrin, respectively; Ac = acetate; py = pyridine and bpy = 2,2′-bipyridine, as well as their corresponding monosubstituted dyads cis- and trans-[B(4-py)BPFPH2{Ru3O(Ac)6(py)2}]PF6 (4a,b) have been structurally characterized via electrospray ionization mass spectrometry (ESI-MS and ESI-MS/MS). The ESI-MS of dyads 4a,b display two characteristic Ru-multicomponent clusters of isotopologue ions corresponding to singly charged ions 4a,b+ of m/z 1629 and doubly charged ions [4a,b+H]2+ of m/z 815 and the triads 5a,b are detected by ESI-MS as the intact doubly charged cluster of isotopologue ions of m/z 1039 [5a,b]2+. The ESI-MS/MS of 4a,b+, [4a,b+H]2+ and [5a,b]2+ reveal characteristic dissociation pathways, which confirm the structural assignments providing additional information on the intrinsic binding strengths of the gaseous ions. Although the gas-phase behavior of each pair of isomers was rather similar, the less symmetric dyads 4a,b are distinguished via the 1H NMR spectral profile of the pyrrolic signals. Exploratory photophysical assays have shown that both modifying motifs alter the porphyrinic core emission profile, opening the possibility to use these asymmetric systems as photophysical devices. 相似文献
108.
Paper-based analytical devices have become lately “must have” components in equipment and instrumental designed for point-of-care applications, especially when they are used in tandem with microfluidic platforms. Nowadays, paper-based electrochemical devices (PEDs) represent the first choice in the development of lab-on-a-chip biosensors because of their benefits in biomedical diagnosis in terms of simplicity, affordability, portability, and disposability. Moreover, cellulose is a biodegradable and biocompatible substrate, ideal for building disposable devices for use in remote locations or low-resource settings. Despite their low costs and simplicity, PEDs must face a tough challenge—meeting the affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and deliverable to end users criteria. The latest achievements in microfluidic PEDs for clinical diagnosis will be critically discussed, putting emphasis on innovative assay formats and methods for surface modification. 相似文献
109.
Adlin N. Ramdzan M. Inês G.S. Almeida Michael J. McCullough Spas D. Kolev 《Analytica chimica acta》2016
A low cost, disposable and easy to use microfluidic paper-based analytical device (μPAD) was developed for simple and non-invasive determination of total aldehydes in saliva with a potential to be used in epidemiological studies to assess oral cancer risk. The μPAD is based on the colour reaction between aldehydes (e.g. acetaldehyde, formaldehyde), 3-methyl-2-benzothiazolinone hydrazone (MBTH) and iron(III) to form an intense blue coloured formazan dye. The newly developed μPAD has a 3D design with two overlapping paper layers. The first layer comprises 15 circular detection zones (8 mm in diameter), each impregnated with 8 μL of MBTH, while the second layer contains 15 reagent zones (4 mm in diameter). Two μL of iron(III) chloride are added to each one of the second layer zones after the addition of sample to the detection zones in the first layer. All hydrophilic zones of the μPAD are defined by wax printing using a commercial wax printer. 相似文献
110.
引入了非齐型齐次Morrey-Herz空间,证明了在非双倍测度情况下,由次线性算子T与RBMO(μ)函数生成的高阶交换子Tb^m=【b,Tb^m-1】在非齐型齐次Morrey—Herz空间上的有界性. 相似文献