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91.
OSHIMA M TOH Y KOIZUMI M KIMURA A Hatsukawa Y MORIKAWA T NAKAMURA M SUGAWARE M KUSAKARI H 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
A new rotational band has been identified and assigned to 188Au for the first time using the 173Yb(19F,4nγ) reaction at the beam energies of 86 and 90 MeV. This band is proposed to be built on the πh9/2 νi13/2 configuration by comparing the band properties with known bands in neighboring nuclei. The prolate-to-oblate shape transition through triaxial shape has been proposed to occur around 188Au for the πh9/2 νi13/2 bands in odd-odd Au isotopes on the basis of total Routhian surface (TRS) calculations. 相似文献
92.
Masashi Shiotsuki Atsushi Nakagawa Jesus Rodriguez Castañon Naoya Onishi Tatsurou Kobayashi Fumio Sanda Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5549-5556
End‐functionalized poly(phenylacetylene)s were synthesized by the polymerization of phenylacetylene (PA) using the well‐defined palladium catalysts represented as [(dppf)PdBr(R)] {dppf = 1,1′‐bis(diphenylphosphino)ferrocene}. The Pd catalysts having a series of R groups such as o‐tolyl, mesityl, C(Ph)?CPh2, C6H4‐o‐CH2OH, C6H4‐p‐CN, and C6H4‐p‐NO2 in conjunction with silver triflate polymerized PA to give end‐functionalized poly(PA)s bearing the corresponding R groups in high yields. The results of IR and NMR spectroscopies and MALDI‐TOF mass analyses proved the introduction of these R groups at one end of each polymer chain. The poly(PA) bearing a hydroxy end group was applied as a macroinitiator to the synthesis of a block copolymer composed of poly(PA) and poly(β‐propiolactone) moieties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
93.
低钠盐及其化验研究 总被引:1,自引:0,他引:1
李京雄 《广东微量元素科学》2003,10(6):60-62
介绍了低钠盐对人体的作用,对低钠盐的定性和定量分析方法进行了研究,包括:低钠盐中镁离子和钾离子的鉴定,用EDTA滴定法测定低钠盐中镁含量和用间接滴定法测定低钠盐中钾含量。 相似文献
94.
Marcel Miglierini Július Dekan Danica Staššíková-Štukovská 《Hyperfine Interactions》2005,166(1-4):651-655
An ancient axe from Early Medieval Age which was unearthed on a territory of the archaeological excavation site near the village Borovce (Slovakia) is investigated. The surface of the axe was supposed to be covered with a sort of glassy system. Mössbauer effect measurements performed in backscattering and transmission geometry upon original as well as powdered pieces of the axe confirmed that the surface layers of the axe consist of goethite, lepidocrite, akageneite, and/or magnetite. After temperature treatment at 400°C/100 min hematite and maghemite were found; these are products of thermal decomposition of the above mentioned iron phases. These findings ruled out the hypothesis that the surface covering substance was put on the axe by intention. 相似文献
95.
96.
Takeshi Endo Yuji Shibasaki Fumio Sanda 《Journal of polymer science. Part A, Polymer chemistry》2002,40(13):2190-2198
This article reviews recent topics in the controlled synthesis of polycarbonates and polylactones with small polydispersity indices by activated monomer cationic ring-opening polymerizations, especially with new initiator systems, such as alcohol/protonic acid and boron alkoxide/protonic acid. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2190–2198, 2002 相似文献
97.
Ralf - Dieter Schindler 《Mathematical Logic Quarterly》1997,43(1):22-28
We show that weakly compact cardinals are the smallest large cardinals k where k+ < k+ is impossible provided 0# does not exist. We also show that if k+Kc < k+ for some k being weakly compact (where Kc is the countably complete core model below one strong cardinal), then there is a transitive set M with M ? ZFC + “there is a strong cardinal”. 相似文献
98.
Ruoyu Hong * Jianmin Ding Guoliang Zheng College of Chemistry Chemical Engineering Soochow University Suzhou P. R. China Institute of Process Engineering Chinese Academy of Sciences Beijing P. R. China IBM HYDA/- C Highway North Rochester MN USA *Author to whom correspondence should be addressed. E-mail: rhong@suda.edu.cn 《中国颗粒学报》2004,2(5):207-214
1. Introduction1.1 Silica nanoparticles and synthesis methods Silica (SiO2) nanoparticles are widely used in industry asan active filler for polymer reinforcement, a rheologicaladditive in fluids, a free flow agent in powders, and anagent for chemical mechanical polishing during IC (inte-grated circuit) fabrication (Sniegowski & de Boer, 2000).Silica powder is also used for producing silicon carbide(Koc & Cattamanchi, 1998) or opaque silica aerosols (Leeet al., 1995). Many methods can … 相似文献
99.
Tuning CO2 Uptake and Reversible Iodine Adsorption in Two Isoreticular MOFs through Ligand Functionalization 下载免费PDF全文
Srinivasulu Parshamoni Suresh Sanda Dr. Himanshu Sekhar Jena Prof. Dr. Sanjit Konar 《化学:亚洲杂志》2015,10(3):653-660
The synthesis and characterization of two isoreticular metal–organic frameworks (MOFs), {[Cd(bdc)(4‐bpmh)]}n?2 n(H2O) ( 1 ) and {[Cd(2‐NH2bdc)(4‐bpmh)]}n?2 n(H2O) ( 2 ) [bdc=benzene dicarboxylic acid; 2‐NH2bdc=2‐amino benzene dicarboxylic acid; 4‐bpmh=N,N‐bis‐pyridin‐4‐ylmethylene‐hydrazine], are reported. Both compounds possess similar two‐fold interpenetrated 3D frameworks bridged by dicarboxylates and a 4‐bpmh linker. The 2D Cd‐dicarboxylate layers are extended along the a‐axis to form distorted square grids which are further pillared by 4‐bpmh linkers to result in a 3D pillared‐bilayer interpenetrated framework. Gas adsorption studies demonstrate that the amino‐functionalized MOF 2 shows high selectivity for CO2 (8.4 wt % 273 K and 7.0 wt % 298 K) over CH4, and the uptake amounts are almost double that of non‐functional MOF 1 . Iodine (I2) adsorption studies reveal that amino‐functionalized MOF 2 exhibits a faster I2 adsorption rate and controlled delivery of I2 over the non‐functionalized homolog 1 . 相似文献
100.
Soumava Biswas Himanshu Sekhar Jena Suresh Sanda Prof. Dr. Sanjit Konar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(39):13793-13801
Three isostructural lanthanide‐based two‐ dimensional coordination polymers (CPs) {[Ln2(L)3(H2O)2]n ? 2n CH3OH) ? 2n H2O} (Ln=Gd3+ ( 1 ), Tb3+ ( 2 ), Dy3+ ( 3 ); H2L=cyclobutane‐1,1‐dicarboxylic acid) were synthesized by using a low molecular weight dicarboxylate ligand and characterized. Single‐crystal structure analysis showed that in complexes 1 – 3 lanthanide centers are connected by μ3‐bridging cyclobutanedicarboxylate ligands along the c axis to form a rod‐shaped infinite 1D coordination chain, which is further linked with nearby chains by μ4‐connected cyclobutanedicarboxylate ligands to form 2D CPs in the bc plane. Viewing the packing of the complexes down the b axis reveals that the lattice methanol molecules are located in the interlayer space between the adjacent 2D layers and form H‐bonds with lattice and coordinated water molecules to form 1D chains. Magnetic properties of complexes 1 – 3 were thoroughly investigated. Complex 1 exhibits dominant ferromagnetic interaction between two nearby gadolinium centers and also acts as a cryogenic magnetic refrigerant having a significant magnetic entropy change of ?ΔSm=32.8 J kg?1 K?1 for ΔH=7 T at 4 K (calculated from isothermal magnetization data). Complex 3 shows slow relaxation of magnetization below 10 K. Impedance analysis revealed that the complexes show humidity‐dependent proton conductivity (σ=1.5×10?5 S cm?1 for 1 , σ=2.07×10?4 S cm?1 for 2 , and σ=1.1×10?3 S cm?1 for 3 ) at elevated temperature (>75 °C). They retain the conductivity for up to 10 h at high temperature and high humidity. Furthermore, the proton conductivity results were correlated with the number of water molecules from the water‐vapor adsorption measurements. Water‐vapor adsorption studies showed hysteretic and two‐step water vapor adsorption (182000 μL g?1 for 1 , 184000 μL g?1 for 2 , and 1874000 μL g?1 for 3 ) in the experimental pressure range. Simulation of water‐vapor adsorption by the Monte Carlo method (for 1 ) confirmed the high density of adsorbed water molecules, preferentially in the interlayer space between the 2D layers. 相似文献