Kinetics of flow stress in ultra-pure tantalum single crystals in stress/temperature regime III

The temperature dependence of the critical resolved shear stress (CRSS), τ, of ultra-pure tantalum single crystals (RRR ≥ 14000) observed below 250 K for a range of shear-strain rates [(g)\dot] = 2×10 ^{- 5} - 6×10 ^{- 3}  \texts ^{- 1} \dot{\gamma } = 2\times 10^{ - 5} - 6\times 10^{ - 3} \,{\text{s}}^{ - 1} was analyzed within the framework of a kink-pair nucleation model of flow stress. The CRSS/strain-rate data follow the model formulation t ^{1/ 2} = C + D  ln[(g)\dot] \tau^{ 1/ 2} = C + D\,{ \ln }\dot{\gamma } , where C and D are positive constants, for each deformation temperature T in the range 78–250 K. Evaluation of the various slip-parameters of flow stress points to (211)[[`1]11] [\bar{1}11] slip system responsible for the yielding of ultra-pure tantalum single crystals in the so-called stress/temperature regime III (T < 250 K). The value of the pre-exponential factor [(g)\dot]_\texto \dot{\gamma }_{\text{o}} in the Arrhenius-type equation for the shear-strain rate [(g)\dot] \dot{\gamma } is found to be of the order of 10⁵ s⁻¹, which is substantially lower than that ( [(g)\dot]_\texto ~ 10⁷  \texts ^{- 1} ) \left( {\dot{\gamma }_{\text{o}} \sim 10^{7} \,{\text{s}}^{ - 1} } \right) determined in the stress/temperature regime II (250–400 K) and contradicts the assumption invariably made in most of the theoretical models of flow stress that [(g)\dot]_\texto \dot{\gamma }_{\text{o}} is a constant over a wide temperature range.     

High-<Emphasis Type="Italic">T</Emphasis><Subscript>C</Subscript> phase transition in K<Subscript>2</Subscript>Ti<Subscript>6</Subscript>O<Subscript>13</Subscript> lead-free ceramic synthesised using solid-state reaction

Solid-state reaction synthesised K₂Ti₆O₁₃ lead-free ceramic was characterized using XRD, SEM, and X-band EPR, at room temperature. EPR-spectra showed the presence of ( \textFe_\textTi^￠ - V_\textO ^·· ) \left( {{\text{Fe}}_{\text{Ti}}^{\prime } - V_{\text{O}}^{ \bullet \bullet } } \right) defect associate dipoles, in orthorhombic phase, responsible for the broadening of the dielectric anomaly identified in the ε _r (T) plots at T _C  ~ 300 °C. This anomaly resembled a ferroelectric–paraelectric type phase transition following Curie–Weiss type trend. Besides, dielectric loss mechanism jointly represented electrical conduction, dipole orientation, and space charge polarization.     

Elastic,piezoelectric, and dielectric properties of lanthanum-gallium tantalate crystals at temperatures of 20–600°C

Measurements of the temperature variations in the relative dielectric constants e₃₃^T/e₀ \varepsilon_{33}^T/{\varepsilon_0} , e₁₁^T/e₀ \varepsilon_{11}^T/{\varepsilon_0} ,and e₂₂^T/e₀ \varepsilon_{22}^T/\varepsilon {}_0 , conductivities g₁₁, g₂₂, and g₃₃, elastic constants C₁₁^D C_{11}^D , C₆₆^D C_{66}^D , and S₂₂^E S_{22}^E , and electromechanical coupling constants k_t, k₂₆, and k₁₂ of lanthanum-gallium tantalate over temperatures of 20–600°C are reported. Data are presented on the effect of lifetime (breakdown) testing on these characteristics of the piezoelectric crystals after retention at a temperature of 625°C for 250 h.     

Phase and morphology evolution of calcium carbonate precipitated by carbonation of hydrated lime

Phase and morphology evolution of CaCO₃ precipitated during carbonation of lime pastes via the reaction Ca(OH)₂ + CO₂ → CaCO₃ + H₂O has been investigated under different conditions (pCO₂ ≈ 10^−3.5 atm at 60 % RH and 93 % RH; pCO₂ = 1 atm at 93 % RH) using XRD, FTIR, TGA, and SEM. Simulations of the pore solution chemistry for different stages and conditions of carbonation were performed using the PHREEQC code to investigate the evolution of the chemistry of the system. Results indicate initial precipitation of amorphous calcium carbonate (ACC) which in turn transforms into scalenohedral calcite under excess Ca²⁺ ions. Because of their polar character, { 21[`3]4 } \left\{ {21\bar{3}4} \right\} scalenohedral faces (type S) interact more strongly with excess Ca<sup>2+</sup> than non-polar { 10[`1]4 } \left\{ {10\bar{1}4} \right\} rhombohedral faces (type F), an effect that ultimately favors the stabilization of { 21[`3]4 } \left\{ {21\bar{3}4} \right\} faces. Following the full consumption of Ca<sup>2+</sup> ions and further dissolution of CO<sub>2</sub> leading to a pH drop of the pore solution, { 21[`3]4 } \left\{ {21\bar{3}4} \right\} scalenohedra are subjected to dissolution. This eventually results in re-precipitation of { 10[`1]4 } \left\{ {10\bar{1}4} \right\} rhombohedra at close-to-neutral pH. This crystallization sequence progresses through the carbonated depth with a strong dependence on the degree of exposure to CO₂, which is controlled by the carbonated pore structure governing the diffusion of CO₂. Both the carbonation process and the scalenohedral-to-rhombohedral transformation are kinetically favored under high RH and high pCO₂. Supersaturation plays a critical role on the nucleation density and size of CaCO₃ crystals. These results have important implications in understanding the behavior of ancient and modern lime mortars for applications in architectural heritage conservation.     

Extensions of access structures and their cryptographic applications

In secret sharing schemes a secret is distributed among a set of users ${\mathcal{P}}In secret sharing schemes a secret is distributed among a set of users P{\mathcal{P}} in such a way that only some sets, the authorized sets, can recover it. The family Γ of authorized sets is called the access structure. To design new cryptographic protocols, we introduce in this work the concept of extension of an access structure: given a monotone family G ì 2^P{{\it \Gamma} \subset 2^\mathcal{P}} and a larger set P^￠ = P è[(P)\tilde]{\mathcal{P}^{\prime} = \mathcal{P} \cup \tilde{\mathcal{P}}}, a monotone access structure G^￠ ì 2^P￠{{\it \Gamma}^{\prime}\subset 2^{\mathcal{P}^{\prime}}} is an extension of Γ if the following two conditions are satisfied: (1) The set P{\mathcal{P}} is a minimal subset of Γ′, i.e. P ? G^￠{\mathcal{P} \in {\it \Gamma}^{\prime}} and P - {R_i} ? G^￠{\mathcal{P} - \{R_i\}\notin {\it \Gamma}^{\prime}} for every R_i ? P{R_i \in \mathcal{P}}, (2) A subset A ì P{A \subset \mathcal{P}} is in Γ if and only if the subset A è[(P)\tilde]{A \cup \tilde{\mathcal{P}}} is in Γ′. As our first contribution, we give an explicit construction of an extension Γ′ of a vector space access structure Γ, and we prove that Γ′ is also a vector space access structure. Although the definition may seem a bit artificial at first, it is well motivated from a cryptographic point of view. Indeed, our second contribution is to show that the concept of extension of an access structure can be used to design encryption schemes with access structures that are chosen ad-hoc at the time of encryption. Specifically, we design and analyze a dynamic distributed encryption scheme and a ciphertext-policy attribute-based encryption scheme. In some cases, the new schemes enjoy better properties than existing ones.     

Inhomogeneous Superconducting State and Intrinsic T c : Near Room Temperature Superconductivity in the Cuprates

Doped cuprates are inhomogeneous superconductors. The concept of an intrinsic critical temperature, T_c^intr. o T_c^*T_{c}^{\mathrm{intr.}} \equiv T_{c}^{*}, whose value greatly exceeds that for the resistive T_c^res. o T_cT_{c}^{\mathrm{res.}}\equiv T_{c}, is supported by a number of experimental studies, including those performed recently. These data are discussed in this review. The anomalous diamagnetism observed at T_c^res. < T < T_c^*T_{c}^{\mathrm{res.}} 相似文献   

The structure of the unidirectionally solidified Al-Al2Au eutectic

The structure of a number of unidirectionally solidified Al-Al₂Au alloys of eutectic and off-eutectic compositions has been investigated over a wide range of growth rates (1.6×10^–4 to 1.66×10^–2cm sec^–1) using a thermal gradient of approximately 80 to 100 lamellar interface || (001)_{Al 2 Au} || (01 1) _Al [ 1 1 0 ]_{Al 2 Au} || [ 1 0 0 ] _Al growth direction of lamellae and rods || [ 1 1 0 ]_{Al2 Au} || [ 1 0 0 ]_Al \begin{gathered} lamellar interface \left\| {(001)_{Al_{ 2} Au} } \right.\left\| {(01 1)} \right._{Al} \hfill \\ \left[ {1 1 0} \right]_{Al_{ 2} Au} \left\| {\left[ {1 0 0} \right]} \right._{Al} \hfill \\ growth direction of \hfill \\ lamellae and rods \left\| {\left[ {1 1 0} \right]_{Al_2 Au} \left\| {\left[ {1 0 0} \right]_{Al} } \right.} \right. \hfill \\ \end{gathered}     

Reduction of a NiO thin film deposited by PLD on a single crystal YSZ (111) substrate

The NiO/YSZ interface prepared by depositing NiO on a single crystal YSZ (111) substrate has been investigated by transmission electron microscopy. As deposited, a very thin nickel layer ascribing to the nonstoichiometry at the very beginning growth of NiO and an amorphous silica phase resulting from silicon segregation were present at the interface. The orientational relationship of NiO (1[`1] 1) (1\overline{1} 1) //Ni (1[`1] 1) (1\overline{1} 1) //YSZ (1[`1] 1) (1\overline{1} 1) with NiO [110]//Ni [110]//YSZ [110] was observed. The microstructural and chemical changes at the NiO/YSZ interface after being heated in vacuum and hydrogen indicated different reduction mechanisms. In vacuum, the reaction \textNiO ? \textNi + 1/ 2 \text O ₂ ( \textg ) {\text{NiO}} \to {\text{Ni}} + 1/ 2 {\text{ O}}_{ 2} \left( {\text{g}} \right) was prevailing at the interface between NiO and pre-existing Ni, which led to the thickening of nickel layer. In hydrogen, the reduction initiated on the NiO surface was dominant, following the chemical equation H₂ + O_O (NiO) → H₂O (g) + V_O ^.. (NiO) + 2e (Ni).     

Evolution of the microstructure and mechanical properties of eutectic Fe<Subscript>30</Subscript>Ni<Subscript>20</Subscript>Mn<Subscript>35</Subscript>Al<Subscript>15</Subscript>

The microstructure of the eutectic alloy Fe₃₀Ni₂₀Mn₃₅Al₁₅ (in at.%) was modified by cooling at different rates from 1623 K, i.e., above the eutectic temperature. The lamellar spacing decreased with increasing cooling rate, and in water-quenched specimens lamellae widths of ~100 nm were obtained. The orientation relationship between the fcc and B2 lamellae was found to be sensitive to the cooling rate. In a drop-cast alloy the Kurdjumov–Sachs orientation relationship dominated, whereas the orientation relationship in an arc-melted alloy with a faster cooling rate was \textfcc( [`1]12 )//\textB2( 0 1 1 );  \textfcc[ 1[`1]1 ]//\textB2 [ 1[`1]1 ]  \textand \textfcc( 0[`1]1 )//\textB2( 00 1 );\text fcc[ 0 1 1 ]//\textB2[ [`1][`1]0 ] {\text{fcc}}\left( {\bar{1}12} \right)//{\text{B2}}\left( {0 1 1} \right);\;{\text{fcc}}\left[ {1\bar{1}1} \right]//{\text{B2 }}\left[ {1\bar{1}1} \right] \,{\text{and}}\,{\text{fcc}}\left( {0\bar{1}1} \right)//{\text{B2}}\left( {00 1} \right);{\text{ fcc}}\left[ {0 1 1} \right]//{\text{B2}}\left[ {\bar{1}\bar{1}0} \right] . The hardness increased with microstructural refinement, obeying a Hall–Petch-type relationship. The strength of the alloy decreased significantly above 600 K due to softening of the B2 phase.     

Large strain response in acceptor- and donor-doped Bi<Subscript>0.5</Subscript>Na<Subscript>0.5</Subscript>TiO<Subscript>3</Subscript>-based lead-free ceramics

Effects of Fe and La addition on the dielectric, ferroelectric, and piezoelectric properties of Bi_0.5Na_0.5TiO₃–Bi_0.5Li_0.5TiO₃–BaTiO₃–Mn ceramics were investigated. Similar to the doping effect in lead-based piezoelectric materials, here the Fe-doped ceramic created a hard effect with an improved mechanical quality factor (Q _m) ~ 160, coercive field (E _c) ~ 2.9 kV/mm, decreased dielectric constant ( e₃₃^T /e₀ ) ~ 80 3, \left( {\varepsilon_{33}^{T} /\varepsilon_{0} } \right)\sim 80 3, and loss (tanδ) ~ 0.024 while the La-doped one indicated a soft feature with improved piezoelectric constant (d ₃₃) ~ 184 pC/N, e₃₃^T /e₀   ~ 983, \varepsilon_{33}^{T} /\varepsilon_{0} \,\sim { 983}, tanδ ~ 0.033, and decreased E _c ~ 2.46 kV/mm. In addition, the temperature dependence of the ferroelectric hysteresis loops and strain response under unipolar electric field was also studied. Around the depolarization temperature T _d, large strain value was obtained with the normalized d₃₃^* d_{33}^{*} up to ~1,000 pC/N, which was suggested originated from the development of the short-range order or non-polar phases in the ferroelectric matrix. All these would provide a new way to realize high piezoelectric response for practical application in different temperature scale.     

Effect of low level substitution of Sr–Ba on transport and magnetic behaviour of La<Subscript>0·67</Subscript>Ca<Subscript>0·33</Subscript>MnO<Subscript>3</Subscript>

In this paper we report the investigation of transition metal oxide compound, La_0·67Ca_0·25Sr_0·04Ba_0·04MnO₃ (LCSBMO), along with La_0·67Ca_0·33MnO₃ (LCMO), synthesized by sol–gel route under identical conditions. The effect of simultaneous low level substitution of large size ions such as Sr²⁺ and Ba^2 + for Ca^2 + ions on the electronic transport and magnetic susceptibility properties are analysed and compared apart from microstructure and lattice parameters. The temperature dependent electrical transport of the polycrystalline pellets of LCSBMO and LCMO when obeying the well studied law, r = r₀ + r₂   T²\rho = \rho_{0} + \rho_{2} \;T^{2} for T < T _MI , is observed to differ by more than 50% from the values of ρ ₀ and ρ ₂, with the former compound showing enhanced electrical conductivity than the latter. Similarly in fitting the adiabatic small polaron model for resistivity data of both the samples for T > T _MI , the polaron activation energy is found to differ by about 11%. In addition, the temperature dependent a.c. magnetic susceptibility study of the compounds shows a shift of about 6% in the paramagnetic to ferromagnetic transition temperature (285 K for LCSBMO and 270 K for LCMO).     

Effect of defect dipoles on the dielectric and electrical properties of Mn:K2Ti6O13 lead-free ceramics: EPR spectroscopy-cum-dielectric-spectroscopy

In this paper, we report the synthesis of Mn:K₂Ti₆O₁₃ lead-free ceramics in a monoclinic phase with microtubular surface morphology via high temperature solid-state reactions. EPR-spectroscopy, achieved at room temperature and at X-band frequencies, recognised Mn²⁺, Mn³⁺, and Mn⁴⁺ partial substitutions at Ti⁴⁺ lattice sites with dominating Mn²⁺ substitution, and identified ( \textFe_\textTi^￠ {\text{Fe}}_{\text{Ti}}^{\prime } – V_\textO ^·· V_{\text{O}}^{ \cdot \cdot } ) and ( \textMn_\textTi^￠￠ {\text{Mn}}_{\text{Ti}}^{\prime \prime } – V_\textO ^·· V_{\text{O}}^{ \cdot \cdot } ) defect associate dipoles exhibited in the low-field EPR signals which smeared with excessive doping due to augmented exchange interactions. These dipoles rendered diffusive nature to the ferroelectric-paraelectric type phase transitions recognized in the ε _r (T) plots. Space charges, dipole orientation, and electrical conduction cooperatively contributed to dielectric losses. The study also provides a select composition with x = 0.05 mol% doping, performing low loss with high dielectric permittivity useful for high-temperature applications. Conductivity data proposed a shift from electronic (hopping) conduction mechanism in the low-temperate region to ionic (intratunnel) conduction at high-temperatures. Whereas slight doping augmented a.c. conductivity due to increased spin-phonon interaction and commanding electron hopping conduction, heavy doping reduced it, attributed to shrinkage of tunnel space and trapping of conduction electrons.     

Thermal characteristics and crystallization kinetics of tellurite glass with small amount of additive As<Subscript>2</Subscript>O<Subscript>3</Subscript>

The crystallization kinetics of the TeO₂/TiO₂/As₂O₃ glassy system was studied under nonisothermal conditions. The method was applied to the experimental data obtained by differential thermal analysis (DTA), using continuous-heating techniques. In addition, two approaches were used to analyze the dependence of glass transition temperature (T _g) on the heating rate (β): One is the empirical linear relationship between (T _g) and (β); The other approach is the use of straight line from the plot of ln( T_\textg² /b ) \textvs . 1/T_\textg \ln \left( {T_{\text{g}}^{2} /\beta } \right)\,{\text{vs}} .\,1/T_{\text{g}} for evaluation of the activation energy for glass transition. The crystallization results are analyzed, and both the activation energy of crystallization process and the crystallization mechanism are characterized.     

The influence of CsBr addition on optical and thermal properties of GeGaS glasses doped with erbium

The influence of the addition of CsBr on the optical and thermal properties of GeGaS glass doped with Er has been being investigated. We find that the addition of CsBr into GeGaS glass leads to some improvements in the radiative properties of Er³⁺ ions in this glass system. The GeGaS–CsBr glasses demonstrate much longer radiative lifetimes and stronger photoluminescence for ⁴I_13/2 ?⁴I_15/2^4\hbox{I}_{13/2} \rightarrow{^4\hbox{I}}_{15/2} and ²H_11/2 ?⁴I_15/2 ^2\hbox{H}_{11/2} \rightarrow{^4\hbox{I}}_{15/2} transitions in Er³⁺ ions. Very low Judd-Ofelt parameters and sharp Er³⁺ absorption spectra with multiple peaks suggest the presence of microcrystals. All optical parameters are strongly influenced by the interplay of Ga and CsBr. The glasses studied have been characterized by their basic glass transformation temperatures. The addition of CsBr into GeGaS glass keeping the ratio between CsBr and Ga close to unity is favorable for the incorporation of larger amount of Er. The experimental results are discussed in terms of structural local arrangement induced by CsBr addition.     

Shear-thickening behaviour of concentrated polymer dispersions under steady and oscillatory shear

The rheological behaviour of a 58 vol.% dispersion of styrene/acrylate particles in ethylene glycol was investigated using a plate-on-plate rheometer. Experimental results showed that the concentrated polymer dispersion exhibited a strong shear-thickening transition under both steady shear and dynamic oscillatory conditions. The low-frequency dynamic oscillatory behaviour could be reasonably interpreted in terms of the steady shear behaviour. Accordingly, the critical dynamic shear rate [(g)\dot]_{\textc_d} , \dot{\gamma }_{{{\text{c\_d}}}} , agreed well with the critical shear rate obtained in steady flow [(g)\dot]_{\textc_s} , \dot{\gamma }_{{{\text{c\_s}}}} , where [(g)\dot]_{\textc_d} \dot{\gamma }_{{{\text{c\_d}}}} was calculated as the maximum shear rate by the critical dynamic shear strain γ _c and the frequency ω, i.e. [(g)\dot]_{\textc_d} = wg_\textc . \dot{\gamma }_{{{\text{c\_d}}}} = \omega \gamma_{\text{c}} . However, during high-frequency dynamic oscillation, it was observed that the shear thickening occurred only when an apparent critical shear strain was reached, which could not be fully explained by the wall-slipping effect. Based on freeze fracture microscopic observations, the effect of the micro-sized flocculation of particles on the rheology of concentrated dispersions was also discussed.     

Parametric study for dewetted Bridgman method: crystal–crucible gap dependence on the Bond and Laplace numbers and on contact angle

In order to analyze the dependence of the crystal-crucible gap on the Bo and La numbers, a parametric study has been performed for two different cases: the sum of the contact angle (θ _c) and the growth angle (α _e) is smaller or larger then 180°. The limit regimes of the main parameters ( La ? - ￥,  La ? + ￥,  Bo ? + ￥,  Bo ? 0 ) \left( {La \to - \infty ,\;La \to + \infty ,\;Bo \to + \infty ,\;Bo \to 0} \right) of the problem were first studied. Then the non-dimensional Laplace equation has been solved numerically in the axi-symmetric case for various values of the parameters and the results are presented as graphical plots. It is shown that the main variations of the gap thickness are localized in the intermediary regimes. Another interesting point is that the gap thickness ([(e)\tilde] ) (\tilde{e} ) shows a maximum when the Bo and La numbers are varied. For growing crystals with a uniform radius, since, by definition, the sensitivity to small variations in the relevant parameter is minimal at the maximum, it is advisable to work at the parameter values which yield a maximum gap size.     

Physicochemical Behavior of Some Amino Acids/Glycylglycine in Aqueous <Emphasis Type="SmallCaps">D</Emphasis>-Galactose Solutions at Different Temperatures

The apparent molar volumes ([`(V<sub>2</sub>)]){(\overline{V_2})} for glycine (Gly), l-alanine (Ala), phenylalanine (Phe), and glycylglycine (Gly-Gly) in 0.10 m aqueous d-galactose solutions have been determined from density measurements at (298.15, 303.15, 308.15, and 313.15) K. The data for ([`(V₂)]){(\overline{V_2})} were utilized to estimate the partial molar volume at infinite dilution ([`(V<sub>2</sub><sup>0</sup>)]){(\overline{V_2^0})} , and experimental slope (S<sub>v</sub><sup>*</sup>){(S_{\rm v}^\ast)} . The transfer volume, ([`(V₂⁰)]_(tr)){(\overline{V_{2}^0}_{\rm (tr)})} , and hydration number, (n _H) were also evaluated. The viscosity data were used to evaluate A- and B-coefficients of the Jones–Dole equation, the free energy of activation of viscous flow per mole of the solvent (Dm₁^0* ){\left(\Delta \mu_{1}^{0\ast} \right)} and the solute (Dm₂^0* ){\left(\Delta \mu _{2}^{0\ast} \right)} . The molar refractivity (R _D) was calculated from refractive index data. The results were discussed in terms of hydrophilic–ionic, hydrophilic–hydrophobic, and hydrophobic–hydrophobic interactions, and structure-making/-breaking ability of the solute (AAs/peptide) in aqueous d-galactose solutions.     

Nanostructured InSiAs solid solution grown by molecular beam epitaxy on the Si(001) surface

The possibility of obtaining a new nanostructured material, an InSiAs solid solution, by molecular beam epitaxy on the Si(001) surface is reported. It is demonstrated that, during simultaneous deposition of indium, silicon, and arsenic, nanometer-size islands with a rectangular base and the sides oriented along the {110} directions can form when the layer thickness exceeds 35 nm. After depositing a 100 nm thick layer of the solid solution, islands with the side ratio d₁₁₀ /d_{1[`1]0</sub> = 1.35d_{110} /d_{1\bar 10} = 1.35 and a typical lateral size of d<sub>1[`1]0} ~ 35 ±10d_{1\bar 10} \sim 35 \pm 10 nm are obtained.     

Certainty equivalent citation: generalized classes of citation indexes

Drawing from the existing literature on risk and inequality measurement, we implement the notion of “certainty equivalent citation” in order (i) to generalize most of the h-type citation indexes (h-, g-, $\tilde{g},$ t-, f-, w-index), and (ii) to highlight the centrality of the decision-maker’s preferences on distributive aspects (concentration aversion) for the ranking of citation profiles. In order to highlight the sensitivity of citation orderings with respect to concentration aversion, an application to both simulated and real citation profiles is presented.     

Journals of general &; internal medicine and surgery: An analysis and comparison of citation

Summary The purpose of this study is to analyze and compare journal citation data, from Journal Citation Reports on the Web 2000, of general and internal medicine and surgery. The source items and five kinds of citation data, i.e. citation counts, impact factor, immediacy index, citing half-life and cited half-life are examined and the correlation between each of the fifteen pairs of citation data is determined based on the Pearson correlation tests. The Fishers Z-transform was employed to test the significant difference between the Pearson correlation coefficient for each pair of citation data of these two subject areas. The following results of this work reveal: the frequently published journals are cited more frequently and also with high impact factor and immediacy index, in addition, they are usually accompanied with short citing half-life (i.e., usually cite current literature). The impact factor and immediacy index has significant correlation with citation counts. A significant correlation also exists between impact factor and immediacy index. However there is no correlation between cited half-life and other citation data, except citing half-life. For journals of general and internal medicine and surgical medicine, there are no significant difference of the Pearson correlation coefficient for the following pair of citation data: source items and citation counts, source items and impact factor, source items and citing half-life, citation counts and citing half-life, impact factor and citing half-life, immediacy index and citing half-life, and cited half-life and citing half-life.