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991.
This article reported the temperature dependence of the electrical resistivity (ρ) of liquid Sn–3.5Ag lead-free solder alloy in continuous heating and cooling processes with varying Bi content in the range of 0, 2, 3.5, 5, and 7?wt.% Abnormal transitions can be observed on ρ–T curves, which indicate liquid–liquid structure transition (LLST) occurs in Sn–3.5Ag–xBi melts. Interestingly, unlike the pattern at first heating cycle, the LLST is reversible during subsequent cooling and heating cycles. Sn may play an important role on the reversibility, and Bi has a noticeable influence on the turning temperatures and characteristics during first heating cycle. The transition mechanism is analyzed from the viewpoint of short-range orders. 相似文献
992.
Abstract The melting curve of NaCl0.5Br0.5 has been measured under pressure up to 4.5 GPa. The melting temperatures of Ag and NaCl have been used to determine the pressure in the sample at its melting temperature. 相似文献
993.
Wilfried B. Holzapfel 《高压研究》2013,33(1):209-216
Equations of State (EOS) for solids under strong compression and wide ranges in temperature are most commonly represented by "parametric" EOS forms using temperature dependent parameters for the volume V 0 , the bulk modulus K 0 , and its pressure derivative K_{0}^{\prime} for the given ambient (or zero) pressure. Therefore, various common "parametric" EOS forms are compared at first with the recently proposed [1,2] A dapted P olynomical expansion AP2, and in the second part with the Mie-Grüneisen approach, which uses one of the common EOS forms for the pressure of the static lattice or for the zero temperature isotherm, p ZT ( V ), and a detailed modelling of the additional thermal pressure, p th ( V , T ), in the form p(V,T) = p_{\rm ZT}(V) + p_{\rm th}(V,T) . Thereby, it is shown, that "intrinsic" anharmonicity effects have to be taken into account and between the two schemes differences of the order of a few percent in pressure are noticed for regular solids, like Cu, Ag, and Au. These differences are discussed with respect to the present uncertainties in a practical pressure scale for wide ranges in pressure (up to several TPa) and in temperature (up to 1500 K and above). 相似文献
994.
Ihor Chumak Volodymyr Pavlyuk Grygoriy Dmytriv Hermann Pauly Helmut Ehrenberg 《ChemInform》2013,44(8):no-no
Li1.95Ag1.05In3 is prepared from the elements (Ta crucible, 1100 °C for 15 min followed by annealing at 150 °C for 1 month) and characterized by single crystal XRD and TB‐LMTO‐ASA computations. 相似文献
995.
Yan Suffren Isabelle Gautier‐Luneau Celine Darie Celine Goujon Murielle Legendre Olivier Leynaud 《ChemInform》2013,44(49):no-no
A new phase of silver iodate, β‐AgIO3, is obtained by heating α‐AgIO3 at 2.7 GPa at <240 °C for 30 min. 相似文献
996.
Bing Jiang Meicheng Li Dandan Song Yingfeng Li Trevor Mwenya 《Crystal Research and Technology》2013,48(12):1044-1049
The Ag nanoparticles with different morphology are directly prepared on Si surface by a facile silver mirror reaction without capping agents and shape‐controlling seeds. Ag nanoplates and Ag polyhedrons are produced on the Si surface by controlling the reaction temperature. Ag nanoplates are easily obtained at the low temperature, which are the products controlled by kinetics pathway. Ag polyhedrons are produced at the high temperature under the combined action of the surface energy and strain energy. Through the catalysis of Ag nanoplates and Ag polyhedrons, different nanoporous structures on the Si surface are obtained using the same etching process, which are useful for the antireflection layers in solar‐cell devices. 相似文献
997.
Ping-Xia Zhang Feng-You Hao Guo-Hua Zhang Xiu-Dan Song Xin-Ying Li 《Molecular physics》2013,111(8):1007-1014
The structures and stabilities of a new class of species, noble-gas–coinage-metal hydroxides NgMOH (Ng =?Ar, Kr and Xe; M =?Cu and Ag), are investigated at the MP2 theoretical level. All species are found to be in Cs symmetry with an approximate linear Ng–M–O moiety. The noble-gas–coinage-metal bond lengths are in the range of the respective covalent and van der Waals limits, showing a different degree of approach to the former along the series Ar–Kr–Xe for Ng–Cu and Ng–Ag bonds, respectively. The dissociation energies of noble-gas–coinage-metal bonds are relatively large as compared to the van der Waals complexes. Besides the charge-induced dipole contribution, other effects –?higher-order charge-induction energies, dispersion interaction, etc., should be considered to explain the noble-gas–coinage-metal bonding mechanism. The present results suggest that the title species are stable enough to be prepared experimentally. 相似文献
998.
Basil Uthuppu Jens Aamand Claus Jørgensen Spire M. Kiersgaard Natalie Kostesha Mogens Havsteen Jakobsen 《Analytica chimica acta》2012
Dichlobenil is an extensively used herbicide worldwide which is transformed to the mobile 2,6-dichlorobenzamide (BAM) in soil. BAM has been found in many European groundwater resources that are exploited for drinking water. Currently, immunoassay based monitoring technique (plate based ELISA) is being employed to quantitatively detect BAM in water samples. In this work, as a starting step of developing immunoassay based on-site monitoring systems for pesticide analysis, the heterogeneous BAM immunoassay is optimised in terms of surface (polymer) regeneration. We have synthesised a small library of BAM haptens which are slightly different in chemical structures, immobilised them on surfaces and compared the affinity constants of the monoclonal antibody HYB 273 towards them. By using ELISA technology, we also have checked the regeneration potentials of the haptens, correlated these results to the affinity constants and found that BAM hapten with an intermediate affinity has better regeneration potential. 相似文献
999.
《Journal of Coordination Chemistry》2012,65(3):448-456
Two new 4d–4f heterometallic coordination polymers [AgLn(pydc)2(H2O)3] · x(H2O) [Ln = Eu, x = 1.25 (1); Ln = Tb, x = 1.25 (2); pydc = 2,6-pyridinedicarboxylate] have been synthesized and characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. Both structures display the same unusual 1-D heterometallic coordination polymer based on Ln building blocks and Ag ions. Thermal stabilities and luminescent properties of 1 and 2 are presented. 相似文献
1000.
《Journal of Coordination Chemistry》2012,65(13):2192-2207
Silver(I) and copper(II) complexes of 4-amino-N-(4,6-dimethyl-2-pyrimidinyl) benzenesulfonamide (smz) have been synthesized and characterized by elemental analysis and infrared (IR), 1H NMR, and UV–vis spectroscopy. [Ag(smz)(pyridine)] (1) crystallizes in monoclinic system with space group P21/c and Z = 4, while [Cu(smz)2(pyridine)2]·H2O (2) crystallizes in triclinic system with space group P-1 and Z = 2. X-ray analysis revealed that silver in 1 is four-coordinate exhibiting distorted tetrahedral geometry, while copper in 2 is coordinated to six nitrogens leading to a highly distorted octahedral geometry. The molecular structures of both 1 and 2 are stabilized by N–H?O and C–H?π intermolecular and C–H?O intramolecular interactions. Water plays a significant role in crystal packing by forming strong N–H?Owater intramolecular as well as Owater–H?N intermolecular interactions in 2. The results of IR, UV–vis, 1H NMR spectral data and thermal analysis for 1 and 2 suggest that the binding of silver and copper to the sulfonamidic nitrogen is in agreement with the crystal structure determination. Antimicrobial activities of silver (1) and copper (2) complexes of sulfamethazine are studied by the dilution method against Staphylococcus aureus and Escherichia coli strains. 相似文献