Synthesis and Structural Determination of Eight Coordinate NH_4[Yb(Ⅲ)(Cydta)(H_2O)_2]·5H_2O

ｅｃａｕｓｅｓｏｍｅｒａｒｅｅａｒｔｈｍｅｔａｌｃｏｍｐｏｕｎｄｓｈａｖｅｔｈｅｐｒｏｍｏｔｉｖｅａｃｔｉｏｎｔｏｔｈｅｇｒｏｗｔｈｏｆａｎｉ ｍａｌｓａｎｄｐｌａｎｔｓ[1 ] ,ａｎｄｔｈｅｆｕｎｃｔｉｏｎｏｆａｎｔｉｉｎ ｆｌａｍｍａｔｉｏｎ ,ａｎｔｉｂａｃｔｅｒｉｕｍ ,ａｎｔｉｃｏａｇｕｌａｎｔｉｏｎａｎｄａｎｔｉｃａｎｅｒ[2 ] ,ｔｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｎｔｈｅｓｙｎ ｔｈｅｓｅｓａｎｄｓｔｒｕｃｔｕｒｅｓｏｆｔｈｅｅｖｅｒｙｋｉｎｄｓｏｆｒａｒｅｅａｒｔｈｍｅｔａｌｃｏｍｐｏｕｎｄｓ…     

稀土脯氨酸高氯酸盐配合物[RE_2(Pro)_6(H_2O)_4](ClO_4)_6(RE=Pr,Er)的低温热容及热力学性质

合成了两种纯度分别是 99.2 4%和 98.2 0 %的单晶稀土脯氨酸高氯酸盐配合物 [Pr2 (Pro) 6 (H2 O) 4](Cl O4) 6 和 [Er2 (Pro) 6 (H2 O) 4](Cl O4) 6 ,对该配合物进行了热容、热重、差热和标准燃烧热等测定。在 78～ 370 K温度区 ,用高精密全自动绝热量热仪测定了热容值 ,计算机拟合得其热容对温度的多项式方程分别为 :Cp=140 7.0 8 75 1.6 7X 170 .17X2 89.5 9X3- 76 .11X4和 Cp=1317.99 6 33.0 5 X 16 3.82 X2 15 0 .2 3X3- 86 .2 1X4,[Er2(Pro) 6 (H2 O) 4](Cl O4) 6 的 Cp- T曲线有一熔化峰 ,计算熔点为 35 5 .5 5 K,熔化熵为 6 9.5 42 J/(K m ol) ,熔化焓为2 472 5 .81J/m ol。 TG、DTA技术研究了其热分解过程 ,初步分析了配合物的分解机理。燃烧热实验给出了它们的标准燃烧热分别为 1772 0 .41k J/mol和 1810 1.6 5 k J/m ol     

Luminescence Properties of Sm^3＋ doped Bi2ZnB2O7

The phosphors of （Bi1- x Smx ） 2ZnB2O7 （ x = 0. 01, 0. 03, 0. 05, 0. 07, and 0. 09） were synthesized by conventional solid state reaction. The purity of all samples was checked by X-ray powder diffraction （XRD）. XRD analysis shows that all these compounds are of a single phase of Bi2ZnB2O7, indicating that the Bi^3＋ in Bi2ZnB2O7 can be partly replaced by the Sm^3＋ without the change of crystal structure. The excitation and emission spectra at room temperature show the typical 4f-4f transitions of Sm^3＋ . The dominant excitation line is around 404 nm due to ^6H5/2→^4K11/2 and the emission spectrum consists of a series of lines at 563, 599, 646, and 704 nm due to ^4G5/2→^6H5/2, ^6H7/2, ^6H9/2, and ^6H11/2, respectively. The optimal concentration of Sm^3＋ in Bi2ZnB2O7 is about 3mol% （relative to lmol Bi^3＋ ） and the critical distance Rc was calculated as 2.1 nm. The temperature dependence of the emission intensity of Bi1.94Sm0.06ZnB2O7 was examined in the temperature range between 100 and 450 K. The quenching temperature where the intensity has dropped to half of the initial intensity is 280 K. The lifetime for Sm^3＋ in Bi1.94Sm0.06ZnB2O7 is fitted as a value of 0.29 and 1.03 ms.     

Blood flow measurements with [(15)O]H2O and [18F]fluoride ion PET in porcine vertebrae

A dual positron emission tomography (PET) tracer study with [18F]fluoride and the freely diffusible tracer [(15)O]H2O was performed to measure the capillary transport of [18F]fluoride and to evaluate the potential of [18F]fluoride ion PET to quantitate bone blood flow. Under the condition of a high predictable single-pass extraction fraction (E(F)) for [18F]fluoride, the [18F]fluoride ion influx transport constant (K1F), derived from kinetic [18F]fluoride ion PET measurements, can be used to estimate bone blood flow. Bone blood flow was measured in vertebral bodies by dynamic [(15)O]H2O PET during continuous ventilation with N2O, O2, and Isoflurane (FiO2 = 0.3) in seven adult mini pigs, followed by dynamic [18F]fluoride ion PET. The mean blood flow measured by [(15)O]H2O (FlowH2O) was 0.145 +/- 0.047 ml x minute(-1) x ml(-1) and the mean K1F was 0.118 +/- 0.031 ml x minute(-1) x ml(-1), respectively (mean +/- SD). Regional analysis showed excellent agreement between FlowH2O and K1F at low flow and a significant underestimation of flow by K1F relative to FlowH2O in regions of normal and elevated flow. The observed relationship between parameters followed the Renkin-Crone distribution. The permeability-surface product was determined as 0.25 minute(-1) for vertebral bodies consisting of a mixture of trabecular and cortical bone. We conclude that [18F]fluoride ion PET can be used to estimate bone blood flow in low and normal flow regions, as long as the flow dependency of the E(F) is taken into consideration. Above blood flow values of 0.2 to 0.35 ml x minute(-1) x ml(-1), the magnitude of K1F is increasingly independent on blood flow because diffusion limits tracer transport.     

The effect of hydrogen on the surface energy of nickel

The effect of hydrogen in solid solution in nickel on the surface and grain boundary free energies at 1573 K was determined using the zero creep technique. Effects of O and H adsorption on the surface free energies were considered and shown to have only small effects under the experimental conditions. The surface energy of pure nickel was determined to be about 2.34 J/m². H concentrations of 300 at. ppm were shown to have no significant effect on the surface energy. Hydrogen had a somewhat greater effect on the grain boundary energy with . The implications of these results for hydrogen embrittlement mechanisms in Ni are discussed.     

Fast ion diffusion,superionic conductivity and phase transitions of the nuclear materials UO<Subscript>2</Subscript> and Li<Subscript>2</Subscript>O

Uranium and lithium oxides are superionic conductors whose solid-state diffusion coefficients are comparable to that of liquids. They are also of technological importance to the nuclear industry. A detailed study of their physical and thermodynamic properties is of great interest for enhanced understanding of these systems. We review our lattice dynamics and molecular dynamics studies carried out on UO₂ and Li₂O in their normal as well as superionic phase. Lattice dynamic calculations have been carried out using shell model in the quasiharmonic approximation. The calculated elastic constants, phonon frequencies and specific heat are in good agreement with the reported experimental data. Lattice dynamics calculations of the thermodynamic properties help validate the interatomic potentials required for undertaking molecular dynamics simulations to study the diffusion behavior in UO₂ and Li₂O. The diffusion constant of Li in Li₂O and O in UO₂ have been determined and compared with the experiment. The calculated superionic transition temperature of Li₂O is 1000 K while that of UO₂ is 2300 K. With the help of molecular dynamics simulations the microscopic picture of the local structure of the lattice just beyond the transition temperature has been deduced. The structural behavior of UO₂ and Li₂O, have also been simulated at high pressure. UO₂ is found to undergo a sluggish transformation to a high-pressure cotunnite phase at about 40 GPa. Similarly Li₂O reveals an anti-fluorite to anti-cotunnite transformation (as reported in angle dispersive X-ray studies) at about 50 GPa. Our lattice dynamical calculations show up similar transformations for UO₂ and Li₂O at 70 and 25 GPa respectively.     

原位还原法制备Al/Al2O3复合材料的力学性质及反应动力学

以石英为先驱体,以液态铝为还原剂,在1073～1523 K的温度范围内对原位生成铝/氧化铝复合材料进行了研究,对获得的复合材料的物理和机械性能做了测定,并对材料显微结构进行了观测和分析.在1473K制备的铝/氧化铝复合材料密度为2.95g/cm3,最大弹性模量为130 GPa,最大三点抗弯强度为580 MPa,最大拉伸强度为268 MPa,洛氏硬度为86.产物铝/氧化铝复合材料的形状与作为先驱体的二氧化硅的形状几乎一致.讨论了反应过程的动力学.     

Synthesis and Crystal Structure of a 4f-3d Complex [La(DMF)_6(H_2O)_3][Cr(CN)_6]·2H_2O

Ｒｅｃｅｎｔｌｙ ,ｔｈｅｒｅｈａｓｂｅｅｎｃｏｎｓｉｄｅｒａｂｌｅｉｎ ｔｅｒｅｓｔｉｎｌａｎｔｈａｎｉｄｅ(Ⅲ )ｈｅｘａｃｙａｎｏｆｅｒｒａｔｅｓａｎｄｔｈｅａｎａｌｏｇｏｕｓｃｏｂａｌｔ(Ⅲ )ａｓｗｅｌｌａｓｃｈｒｏｍｉｕｍ(Ⅲ )ｃｏｍｐｌｅｘｅｓｂｅｃａｕｓｅｏｆｔｈｅｉｒｐｏｔｅｎｔｉａｌａｓｃａｔａｌｙｔｉｃ ,ｓｅｍｉｃｏｎｄｕｃｔｉｖｅ ,ａｎｄｍａｇｎｅｔｉｃｍａｔｅ ｒｉａｌｓ[1～ 4] .Ｆｏｒｅｘａｍｐｌｅ ,ｍａｇｎｅｔｉｃｓｔｕｄｉｅｓｏｎａｓｅｒｉｅｓｏｆｔｈｒｅｅ ｄｉｍｅｎｓｉｏ…     

Water and solute activities of the solution systems of H2So4-Cuso4-H2O and Hci-Cuci2-H2O

The activities of water, α(H₂O), in the solution system of H₂SO₄-CuSO₄-H₂O were determined by an isopiestic method and those in the solution system of HCl-CuCl₂-H₂O by a transpiration method, both at 298 K. The activities of H₂SO₄ and H⁺ in the solution system of H₂SO₄-CuSO₄-H₂O were also determined at 298 K by the emf method. The water activities in both systems obeyed the Zdanovskii rule relatively well. The α(H₂O) experimentally determined in the sulfate system showed a satisfactory agreement with those calculated from the Robinson-Bower equation, assuming the complete dissociations of H₂SO₄ and CuSO₄, whereas a good agreement between the calculated and experimentally determined α(H₂O) for the chloride system was obtained when the formation of Cu(II) chloro-complexes was taken into consideration. The mean activity coefficients, γ_±, of solutes, including H₂SO₄, HC1, and CuCl₂ in these solution systems, were calculated at 298 K by the McKay-Perring method using the activity data. The γ_±(H₂SO₄) values in the solution system of H₂SO₄-CuSO₄-H₂O were in good agreement with those determined by the emf method. On the other hand, the γ_±(CuSO₄) were calculated at the same temperature based upon the Gibbs-Duhem equation using both measured α(H₂O) and calculated γ_±(H₂SO₄) values, because of solubility limitations.     

Stress-induced interaction of pairs of point defects in bcc solutions

The theory of the stress-induced interaction1 has been used to calculate the interaction energies of interstitials, vacancies as well as interstitials and vacancies, and host atom displacements around a vacancy and interstitial in four metals with the bcc lattice: aFe, V, Nb, and Ta. The cases of interstitial location both in octahedral and tetrahedral interstices are discussed. The elastic constants, cohesion energy (for vacancies), Born-Karman constant of the host lattice and coefficients of the concentration expansion of the solid solution lattice due to the interstitials are the numerical parameters of the theory. The computer calculation was carried out in the general form suitable for any interstitial in these four metals and specifically for the interstitial solutions H, O, N in V, Nb, Ta and C, and N in aFe. In the only case when the quantitative comparison of the calculated characteristics with the experimental one is possible (interaction of the vacancies with C in aFe), there is good agreement between calculated and observed values.     

Hydrothermal synthesis, crystal structure and magnetic properties of a Dy~Ⅲ-Fe~Ⅲ heteronuclear complex

A new 3d-4f heteronuclear complex [Fe(phen)3]2[FeDy(H2O)(tiron)3]·6H2O (1,Na2H2tiron=disodium 4,5-dihydro-xybenzene-1,3disulfonate) was synthesized by the hydrothermal reaction. The complex crystallized in the cubic system, space group P213 with the cell parameters:a=2.18786(14)nm, V=10.4727(12)nm3 , Z=4, F(000)=4720, R1=0.0493, wR2 =0.1165, S=1.05. In each [FeDy(H2O)(tiron)3]6-unit, it was revealed that the Fe3+ ion was in a FeO6 distorted trigonal anti-prism coordination polyhedron completed by six phenolate O atoms from three tiron 4- ligands, while Dy3+ in a DyO7 distorted monocapped trigonal anti-prism coordination polyhedron completed by three phenolate μ2-O atoms and three O atoms from sulfonate groups of three ligands and one O atom from water. The magnetic properties of the complex was determined in the range of 2-300K, indicating the antiferromagnetic interaction between the central DyIII-FeIII ions.     

Conformational changes in conantokin-G induced upon binding of calcium and magnesium as revealed by NMR structural analysis

The apo- and metal-bound solution conformations of synthetic conantokin-G (con-G, G1Egamma gammaL5Q gamma NQgamma 10LIRgamma K15SN-CONH2, gamma = gamma-carboxyglutamic acid), an antagonist of N-methyl-D-aspartate receptor-derived neuronal ion channels, have been examined by one- and two-dimensional 1H NMR at neutral pH. A complete structure for the Mg2+-loaded peptide was defined by use of distance geometry calculations and was found to exist as an alpha-helix that spans the entire peptide. The alpha-helical nature of Mg2+/con-G was also supported by the small values (<5.5 Hz) of the 3JHNalpha coupling constants measured for amino acid residues 3-5, 8, 9, and 11-16, and the small values (<4 ppb/K) of the temperature coefficients observed for the alphaNH protons of residues 5-17. This conformation contrasted with that obtained for apo-con-G, which was nearly structureless in solution. Docking of Mg2+ into con-G was accomplished by use of the genetic algorithm/molecular dynamics simulation method, employing the NMR-derived Mg2+-loaded structure for initial coordinates in the midpoint calculations. For the 3 Mg2+/con-G model, it was found that binding of one Mg2+ ion is stabilized by oxygen atoms from three gamma-carboxylates of Gla3, Gla4, and Gla7; another Mg2+ is coordinated by two oxygen atoms, one from each of the gamma-carboxylates of Gla7; and a third metal ion through three donor oxygen atoms of gamma-carboxylates from Gla10 and Gla14. As shown from direct metal binding measurements to mutant con-G peptides, these latter two Gla residues probably stabilized the tightest binding Mg2+ ion. Circular dichroism studies of these same peptide variants demonstrated that all Gla residues contribute to the adoption of the Mg2+-dependent alpha-helical conformation in con-G. The data obtained in this investigation provide a molecular basis for the large conformational alteration observed in apo-con-G as a result of divalent cation binding and allow assessment of the roles of individual Gla residues in defining certain of the structure-function properties of con-G.     

Global analysis of the thermal and chemical denaturation of the N-terminal domain of the ribosomal protein L9 in H2O and D2O. Determination of the thermodynamic parameters, deltaH(o), deltaS(o), and deltaC(o)p and evaluation of solvent isotope effects

The stability of the N-terminal domain of the ribosomal protein L9, NTL9, from Bacillus stearothermophilus has been monitored by circular dichroism at various temperatures and chemical denaturant concentrations in H2O and D2O. The basic thermodynamic parameters for the unfolding reaction, deltaH(o), deltaS(o), and deltaC(o)p, were determined by global analysis of temperature and denaturant effects on stability. The data were well fit by a model that assumes stability varies linearly with denaturant concentration and that uses the Gibbs-Helmholtz equation to model changes in stability with temperature. The results obtained from the global analysis are consistent with information obtained from individual thermal and chemical denaturations. NTL9 has a maximum stability of 3.78 +/- 0.25 kcal mol(-1) at 14 degrees C. DeltaH(o)(25 degrees C) for protein unfolding equals 9.9 +/- 0.7 kcal mol(-1) and TdeltaS(o)++(25 degrees C) equals 6.2 +/- 0.6 kcal mol(-1). DeltaC(o)p equals 0.53 +/- 0.06 kcal mol(-1) deg(-1). There is a small increase in stability when D2O is substituted for H2O. Based on the results from global analysis, NTL9 is 1.06 +/- 0.60 kcal mol(-1) more stable in D2O at 25 degrees C and Tm is increased by 5.8 +/- 3.6 degrees C in D2O. Based on the results from individual denaturation experiments, NTL9 is 0.68 +/- 0.68 kcal mol(-1) more stable in D2O at 25 degrees C and Tm is increased by 3.5 +/- 2.1 degrees C in D2O. Within experimental error there are no changes in deltaH(o) (25 degrees C) when D2O is substituted for H2O.     

Water and solute activities of the solution systems of H2So4-Cuso4-H2O and Hci-Cuci2-H2O

The activities of water, α(H₂O), in the solution system of H₂SO₄-CuSO₄-H₂O were determined by an isopiestic method and those in the solution system of HCl-CuCl₂-H₂O by a transpiration method, both at 298 K. The activities of H₂SO₄ and H⁺ in the solution system of H₂SO₄-CuSO₄-H₂O were also determined at 298 K by the emf method. The water activities in both systems obeyed the Zdanovskii rule relatively well. The α(H₂O) experimentally determined in the sulfate system showed a satisfactory agreement with those calculated from the Robinson-Bower equation, assuming the complete dissociations of H₂SO₄ and CuSO₄, whereas a good agreement between the calculated and experimentally determined α(H₂O) for the chloride system was obtained when the formation of Cu(II) chloro-complexes was taken into consideration. The mean activity coefficients, γ_±, of solutes, including H₂SO₄, HC1, and CuCl₂ in these solution systems, were calculated at 298 K by the McKay-Perring method using the activity data. The γ_±(H₂SO₄) values in the solution system of H₂SO₄-CuSO₄-H₂O were in good agreement with those determined by the emf method. On the other hand, the γ_±(CuSO₄) were calculated at the same temperature based upon the Gibbs-Duhem equation using both measured α(H₂O) and calculated γ_±(H₂SO₄) values, because of solubility limitations.     

Study of Interfacial Tension between Molten Steel and Na_2O-Li_2O-SiO_ 2-B_2O_3 Slag

Ｔｈｅｒｅａｒｅｍａｎｙｃａｓｅｓｗｈｅｒｅｔｈｅｉｎｔｅｒｆａｃｅｂｅ ｔｗｅｅｎｍｏｌｔｅｎｍｅｔａｌａｎｄｓｌａｇｐｌａｙａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｔｈｅｓｔｅｅｌｍａｋｉｎｇ ｐｒｏｃｅｓｓｓｕｃｈａｓｔｈｅｆｏｒｍａｔｉｏｎ ,ａｇｇｒｅｇａｔｉｏｎ ,ｄｉｓｔｒｉｂｕｔｉｏｎａｎｄｓｉｚｅｏｆｎｏｎ ｍｅｔａｌｌｉｃｉｎ ｃｌｕｓｉｏｎｓｉｎｓｔｅｅｌ ,ｆｏｒｍａｔｉｏｎｏｆｍｅｔａｌ ｉｎ ｓｌａｇｅｍｕｌｓｉｏｎｉｎｔｈｅＢＯＦｐｒｏｃｅｓｓａｎｄｓｌａｇ ｍｅｔａｌｒｅａｃｔｉｏ…     

75Cr1钢加热炉内表面脱碳分析

在实验室模拟现场加热炉加热过程,在CO_2、O_2、H_2O、N_2体积分数分别为16.5%、0.8%、13%、69.7%的混合气氛下对75Cr1钢加热保温。通过正交实验研究了加热温度(975、1 050、1 125、1 200℃)和保温时间(10、20、30、40min)对75Cr1钢脱碳的影响规律。并与菲克第二定律的计算结果进行了对比。实验结果表明:脱碳层深度随着加热温度和保温时间的增加而增加,并且当温度为1 200℃时,增幅明显变大;975℃时的实测值接近理论值,1 050、1 125、1 200℃时,实测值远小于理论值;扩散系数修正后计算值与实测值基本保持一致。     

Effects of temperature on the kinetics of the gated electron-transfer reaction between zinc cytochrome c and plastocyanin. Analysis of configurational fluctuation of the diprotein complex

This is a study of the effects of temperature (in the range 273.3-307.7 K) and of ionic strength (in the range 2.5-100 mM) on the kinetics of photoinduced electron-transfer reaction 3Zncyt/pc(II)--> Zncyt+/pc(I) within the electrostatic complex of zinc cytochrome c and cupriplastocyanin at pH 7.0. In order to separate direct and indirect effects of temperature on the rate constants, viscosity of the solutions was fixed, at different values, by additions of sucrose. The activation parameters for the reaction within the preformed complex, at the low ionic strength, are delta H++ = 13 +/- 2 kJ/mol and delta S++ = -97 +/- 4 J/K mol. The activation parameters for the reaction within the encounter complex, at the higher ionic strength, are delta H++ = 13 +/- 1 kJ/mol and delta S++ = -96 +/- 3 J/K mol. Evidently, the two complexes are the same. The proteins associate similarly in the persistent and the transient complex, i.e., at different ionic strengths. In both complexes, however, electron transfer is gated by a rearrangement, as previous studies from this laboratory showed. Changes in the solution viscosity modulate this rearrangement by affecting delta H++, not delta S++. The activation parameters are analyzed by empirical methods. The thermodynamic parameters delta H and delta S for the formation of the complex Zncyt/pc(II) are determined and related to changes in hydrophilic and hydrophobic surfaces upon protein association in three configurations. A difference between the values of delta H for the configuration providing optimal electronic coupling between the redox sites and the configuration providing optimal docking equals the experimental value delta H++ = 13 kJ/mol for the rearrangement of the latter configuration into the former. Enthalpy of activation may reflect a change in the character of the exposed surface as the diprotein complex rearranges. Entropy of activation may reflect tightening of the contact between the associated proteins.     

Determination of the seven apparent equilibrium constants for the binding of oxygen by hemoglobin from measured fractional saturations

Subunit dissociation has to be taken into account in the determination of the oxygen binding constants of hemoglobin, as described by Ackers and Halvorson in 1974. The seven apparent equilibrium constants for a particular set of conditions can be determined by using extrapolations to determine the fractional saturations YT of tetramer and YD of dimer from measured values of the fractional saturation Y of partially dissociated hemoglobin. Analytical methods are used to show that YT as a function of [O2] for tetramers can be calculated from Y of hemoglobin by linear extrapolation of measured Y values at high [heme] versus [heme]-1/2 to [heme]-1/2 = 0. YD for dimers can be calculated from measured Y values by linear extrapolation of Y versus [heme] to [heme] = 0 if sufficiently low [heme] can be used. These extrapolations have been tested with numerical calculations of Y for a particular hemoglobin as a function of [heme] and [O2] by using the seven apparent equilibrium constants determined by Mills, Johnson, and Ackers in 1976. The proposed procedure also yields the apparent association constant K" for 2TotD = TotT, where TotD is the sum of the dimers and TotT is the sum of the tetramers. This thermodynamic analysis of experimental data to determine the seven apparent equilibrium constants is independent of the model used to interpret the values of the thermodynamic parameters.     

Martensite crystal lattice,mechanism of austenite-martensite transformation and behavior of carbon atoms in martensite

Results concerning the crystal lattice of freshly formed martensite with abnormally low and abnormally high axial ratioc/a as well as the results of neutron diffraction studies of the positions of carbon atoms are reviewed. Mechanisms of the austenite to martensite transformation are considered, which can explain the formation of martensite with differentc/a for the same carbon content in the initial austenite. Occurrence of (011)m transformation twins explains both a lowering ofc/a and an orthorhombic distortion of the martensite lattice. It follows from analysis of the experimental results that the well known dependence of martensite lattice parameters and axial ratio on the carbon content relate to a partly disordered distribution of carbon atoms between three sublattices of the octahedral interstitial sites (ois). Using new values of the concentration coefficients of linear expansion of the martensite lattice, calculated for the case of carbon atoms distribution only in a single sublattice of the ois, leads to some corrections of the previous temperature and concentration dependences of order-disorder processes in martensite. Phenomena such as the reversible change of axial ratio due to the redistribution of carbon atoms between their normal positions and “traps” in irradiated martensite are described.     

Density of Na2O-Li2O-SiO2-B2O3 Molten Slag at 1 803——1 873 K

The density of three kinds of molten slags was measured by modified sessile dropmethod at 1 803 1 873 K. The density of molten slag is found to decrease with increasing tem-perature. The temperature coefficients of Na2 O-Li2--SiO2 and Li2O-SiO2-B2O3 slag are smallerthan that of Na20-B2O3 slag. The molar volume of slags increases with increasing temperature.