六十年代中期中共转变经济建设方针的原由

六十年代中期中共转变经济建设方针的原由王培从１９６４年４月至１９６５年９月，在研究制定“三五”计划的过程中，中共中央改变集中解决吃穿用的方针，做出加快三线建设的决策。这个转变关系到全局的部署，对经济建设产生了深远的影响。本文具体探讨三线建设决策的原由...

New atom movement mechanism for tracking path on disordering AuCuI(A_8^(Au)A_4^(Cu)) compound

Taking experimental path on disordering AuCuI（AAuCu8A4）composed of A Au8 and ACu4 stem alloy genes as an example, three discoveries and a method were presented. The ability of Au Cu I（AAu Cu8 A4）to keep structure stabilization against changing temperature is attributed to the fact that the AAu8 and ACu4 potential well depths greatly surpass their vibration energies, which leads to the subequilibrium of experimental path. A new atom movement mechanism of AuCuI（AAuACu84）to change structure for suiting variation in temperature is the resonance activating-synchro alternating of alloy genes, which leads to heterogeneous and successive subequilibrium transitions. There exists jumping order degree, which leads to the existence of jumping Tj-temperature and an unexpected so-called ＂retro-effect＂ about jumping temperature retrograde shift to lower temperatures upon the increasing heating rate. A set of subequilibrium holographic network path charts were obtained by the experimental mixed enthalpy path method.

Microstructure and strengthening mechanism of Mg-5.88Zn-0.53Cu-0.16Zr alloy solidified under high pressure

Mg-5.88 Zn-0.53 Cu-0.16 Zr(wt.%)alloy was solidified at 2-6 GPa using high-pressure solidification technology.The microstructure,strengthening mechanism and compressive properties at room temperature were studied using SEM and XRD.The results showed that the microstructure was refined and the secondary dendrite spacing changed from 35μm at atmospheric pressure to 10μm at 6 GPa gradually.Also,Mg(Zn,Cu)2 and Mg Zn Cu eutectic phases were distributed in the shape of network,while under high pressures the second phases(Mg(Zn,Cu)2 and Mg7 Zn3)were mainly granular or strip-like.The solid solubility of Zn and Cu in the matrix built up over increasing solidification pressure and reached 4.12%and 0.32%respectively at 6 GPa.The hardness value was HV 90 and the maximum compression resistance was 430 MPa.Therefore,the grain refinement strengthening,the second phase strengthening and the solid solution strengthening are the principal strengthening mechanisms.

Covariant Prolongation Structure of Konno-Asai-Kakuhata Equation

Based upon the covariant prolongation structures theory, we construct the sl（2, R）×R（p） prolongation structure for Konno-Asai-Kakuhata equation. By taking two and one-dimensional prolongation spaces, we obtain the inverse scattering equations given by Konno et al. and the corresponding Riccati equation. The Baecklund transformations are also presented.

Non-isothermal curing kinetics and thermal properties of benzoxazine-phenolic copolymers

Using novolac phenolic resin, aniline and formaldehyde as raw materials, benzoxazine-phenolic copolymers with different percentages of benzoxazine rings were prepared. FT-IR was adopted to characterize the molecular structure of the novolac-type phenolic resin and the benzoxazine-phenolic copolymer BP31. In order to understand the curing process of the copolymers, the curing behavior and curing kinetic characteristics were studied by differential scanning calorimetry （DSC）, and the catalytical effect of phenolic hydroxyl on the curing behavior of copolymers was investigated. To investigate the thermal properties of this resin, the thermal degradation behaviors of the cured samples were studied by thermal gravimetric （TG） method, and glass-transition temperatures （Tg） of the cured copolymers were also evaluated by DSC. The dynamic Ozawa method was adopted to determine the kinetic parameters of the curing process as well. The activation energy is 78.8 kJ/mol and the reaction rate constant is in the range from 40.0 to 5.2 （K/min）＂ according to reaction temperatures. The Ozawa exponent decreases from 2.4 to 0.7 with the increase of reaction temperature, and curing mechanism is expounded briefly according to the results. TG result shows that the highest char yield of copolymers is 50.3%. The highest Tg of copolymers is 489 K, which is much higher than that of pure benzoxazine resin.

Fully degradable brush polymers with polycarbonate backbones and polylactide side chains

Novel, fully degradable brush polymers with polycarbonate backbones and polylactide side chains were prepared by a three-step reaction that included the terpolymerization of cyclohexene oxide （CHO） and benzyl glycidyl ether （BGE） with CO2, hydrogenation of the resultant terpolymers to afford the terpolymers with 1,2-glycerol carbonate units and the 1,8-diazabicyclo[5.4.0]undec-7-ene （DBU） mediated ring-opening polymerization of lactide on the polycarbonate backbone. The brush copolymer bearing polylactide （PLA） chains from racemic lactide （rac-LA） has a single glass-transition temperature of 58.5 ℃, whereas the copolymers with （L）-PLA side chains exhibited a melting enthalpy at 135.8 ℃ with AHm=25.04 J/g and were further shown by a WAXD study to be a typical semicrystalline polymer with sharp diffraction peaks at 20 values of 16.7° and 18.9°.

A Result on the Quasi-periodic Solutions of Forced Isochronous Oscillators at Resonance

In this paper, the authors are concerned with the forced isochronous oscillators with a repulsive singularity and a bounded nonlinearity x'' + V'(x) + g(x) = e(t, x, x'),where the assumptions on V, g and e are regular, described precisely in the introduction.Using a variant of Moser's twist theorem of invariant curves, the authors show the existence of quasi-periodic solutions and boundedness of all solutions. This extends the result of Liu to the case of the above system where e depends on the velocity.

The abnormal behavior of polymers glass transition temperature increase and its mechanism

In terms of the classical theory in textbooks, the two components with phase separation in a binary polymer blend will, depending on their compatibility, have their respective Tg get closer or remain in their original values. According to the classical theory, the Tg of plastic component shall remain unchanged or move toward the lower Tg of rubber component in a rubber/plastic blend. However, ultra-fine full-vulcanized powdered rubber (UFPR) with a diameter of ca. 100 nm can simultaneously increase the toughness and the Tg of plastics, which is abnormal and is difficult to explain by classical theory. In this feature article, the abnormal behavior and its mechanism are discussed in detail.

Electron transfer photochromism of Ln-based(Ln=Dy,Tb)coordinated behavior

Switching on/off single-molecule magnets(SMMs)at room temperature is still a challenge in moleculebased magnets.Herein,two photochromic Ln-based(Ln=Dy,Tb)phosphonate coordinated polymers were synthesized with regulable SMM behavior.The reversible room-temperature photo-coloration was an electron transfer process with a generation of relatively stable radicals,characterized by structural analyses,ultraviolet-visible,luminescence and electron spin resonance spectra and magnetic measurements.Importantly,owing to the antiferromagnetic coupling interactions between Ln^(3+) ions and photogenerated radicals,the room-temperature light irradiation surprisingly switched off the SMM behavior,showing the first example of radicalquenched SMMs in the molecule-based magnets.Moreover,the silient SMM behavior could be recovered after eliminating photogenerated radicals via heat treatment,showing a reversible off/on switch of SMMs via light and heat.This work constructs a system for switching off/on SMMs through electron transfer photochromism,providing a visual operation way via naked-eye-detectable coloration for the switchable SMMs.