Pritchard-Salamon系统的可稳定化性和代数Riccati方程

在本文中，我们给出了光滑Pritchard－Salamon系统（简称PS系统）能以紧算子为可容反馈可稳定化的充分必要条件．应用此结果，我们给出了光滑PS系统中的代数Riccati方程的所有非负自伴解的参数化表示，把[1]中的主要结果推广到了光滑PS系统．

动态模型的建立及其它

诺贝尔经济获得者丁伯根等解决了用2个手段控制2个目标的经济问题。本文建立起用 n 个手段控制 m 个目标的线性微分动力系统;综述现代国外学者有关线性微分动力系统稳定性的成果;提出矩阵的差分稳定性和微分稳定性概念,以及更新教材内容的意见。

Evolutionary Game Dynamics in a Fitness-Dependent Wright-Fisher Process with Noise

Evolutionary game dynamics in finite size populations can be described by a fitness-dependent Wright- Fisher process. We consider symmetric 2×2 games in a well-mixed population. In our model, two parameters to describe the level of player＇s rationality and noise intensity in environment are introduced. In contrast with the fixation probability method that used in a noiseless case, the introducing of the noise intensity parameter makes the process an ergodic Markov process and based on the limit distribution of the process, we can analysis the evolutionary stable strategy （ESS） of the games. We illustrate the effects of the two parameters on the ESS of games using the Prisoner＇s dilemma games （PDG） and the snowdrift games （SG）. We also compare the ESS of our model with that of the replicator dynamics in infinite size populations. The results are determined by simulation experiments.

Immobilization of metal-organic molecular cage on g-C3N4 semiconductor for enhancement of photocatalytic H2 generation

A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used to characterize structure of hybrid MOC-16/g-C3N4, as well as UV-vis absorption spectrum and X-ray photoelectron spectroscopy were carried out to unveil photocatalytic mechanism. With the introduction of MOC-16, the absorption edge of MOC-16/g-C3N4 in UV-vis spectrum extended apparently to long-wavelength region compared with pristine g-C3N4. H2 evolution yielded with MOC-16/g-C3N4 in aqueous solution containing TEOA was much higher than that with RuL3/g-C3N4, Pd/RuL3/g-C3N4 and mixture of MOC-16 and g-C3N4, showing that the octahedral cage structure with high-efficient electron transfer and the interface interaction between MOC-16 and g-C3N4 were significant for improvement of H2 evolution.

Effect of Complexation with Hydroxylpropyl-β-Cyclodextrin on Solubility, Dissolution Rate and Chemical Stability of Prostaglandin E1

Aim To study the effect of complexation with hydroxylpropyl-β-cyclodextrin(HP-β-CD) on the solubility, dissolution rate and chemical stability of prostaglandin E_1 (PGE_1) ,thereby providing a basis for preparing a stable solid or aqueous preparation of PGE_1 formulatedwith HP-β-CD. Methods The effect of HP-β-CD on the solubility of PGE_1 was studied by phasesolubility method. The formation of inclusion complexes of PGE_1 with HP-β-CD in the aqueoussolution was confirmed by UV spectra, circular dichroism spectroscopy, and that in the solid stateby IR spectra and X-ray diffractome-try. An solid inclusion complex of PGE_1 with HP-β-CD wasprepared by lyophilization. The dissolution rate and stability of the inclusion complex weredetermined and compared with those of PGE_1 alone. Meanwhile, the stability of PGE_1 aqueoussolutions in the presence of HP-β-CD was studied under different pH conditions. Results Thesolubility of PGE_1 increased linearly with increasing HP-β-CD concentration in various pH bufferedsolutions, showing typical A_L-type phase solubility diagrams. The stability and dissolution rateof the solid inclusion complex of PGE_1 were significantly increased, compared with those of purePGE_1 . The stability of PGE_1 in HP-β-CD solutions was also obviously improved under acidic andbasic conditions, but the stabilizing effect was absent under neutral conditions. Conclusions Thesolubility,dissolution rate and chemical stability of PGE_1 are markedly improved by complexationwith HP-β-CD: It is quite possible to prepare a stable PGE_1 inclusion complex-containing soliddosage forms, but almost impossible to obtain a stable aqueous preparation of PGE_1 formulated withHP-β-CD.

Correlation of Cooperatively Localized Rearrangement on the ＂Fluidized Domain＂ of Polymers to Their Nonexponentially Viscoelastic Behavior and Lifetime at Double Aging Processes II： Estimation of Long-term Mechanical Behavior and Lifetime of Polymeric Materials from Short-time Creep and Stress Relaxation Tests

Three kinds of polymeric materials are taken as example for the verification of linear ex-trapolation method from unified master lines with reduced universal equations on creep and stress relaxation tests. The theoretical values of long-term mechanical behavior and lifetime for a cured epoxide, polypropylene, poly（methyl-methacrylate）, and SBR rubber are directly evaluated with the universal equations on reduced creep compliance and reduced stress relax-ation modulus and are compared with their predicted values by the linear extrapolation from the unified master lines of creep and stress relaxation. The results show that the theoretical values of dimensional stability, bearing ability and lifetime are in an excellent agreement with the predicted values, it shows that the linear extrapolation method is more simple and reliable. The dependences of long-term mechanical behaviors and lifetime on the different aging times are discussed.

Traditional Structures Technologies in Tekye-Amir-Chakhmagh

Iranian traditional architecture can be identified in many of its old famous buildings in the country. The principles and specifications in these buildings show the intelligence of implemented techniques that makes them to remain stable. Thus, it is important to explore the traditional structures and architectural technologies in order to understand the reasons for this stability toward the new methods in modem architecture. Many of historical buildings in Iran have remained standing after many years and they show the deep wisdom of their architects. The purpose of this article is studying the various aspects of traditional structure and integration between this well-oriented structure and architecture. For reaching this goal, we refer to Tekye-Amir-Chakhmagh in Yazd as our case study, which is one of the most important and noticeable examples of Iranian traditional architecture. By introducing Amir-Chakhmagh Complex, we analyzed the specifications and fundamental elements that played an important role in stability and sustainability of Tekye-Amir-Chakhmagh and thereafter, we assessed the technologies that were used intelligently and intricately in this historical building. In this research, information is collected with field study and library resources. Finally, qualities and characteristics of the structure are studied by drawings and structural analysis and as conclusion, the suggestions and guidelines are presented.

Large eddy simulation of a 3-D spatially developing turbulent round jet

A three-dimensional large eddy simulation （LES） of a spatially developing round jet is carried out in cylindrical coordinates using a dynamic subgrid model with strong inflow instability. Evolutions of large-scale vortex structures represented by tangential vortices are obtained and compared with flow visualization. Also presented are three-dimensional spatial evolutions of coherent structure, which are of quasi two-dimensional Kelvin-Helmholtz instability and vortex rings as well as breaking up of the vortex rings with fully three-dimensional characteristics. Predicted results of mean velocity and turbulent intensity agree well with experiments. They are also compared with the results predicted by LES using standard Smagorinsky model and show good self-similarity. Turbulence spectrum of the predicted velocity shows the -5/3 decay for higher wave number, as expected for turbulent round jet flows. In addition, fl-test and y-test are carded out for the instantaneous velocity, showing that the present LES method can successfully predict the hierarchical structure of round jet.

Magnetically responsive photonic films with high tunability and stability

We demonstrate the fabrication of magnetically assembled one-dimensional chain-like photonic nanostructures with significantly high photonic stability. The key lies in the use of agarose hydrogel to prevent coagulation of the magnetic assemblies. When exposed to an external magnetic field, negatively charged Fe3O4@SiO2 particles can effectively assemble in the hydrogel matrix into one- dimensional chains with internal periodicity and display a fast, fully reversible, and tunable photonic response to the changes in the external field. The steric hindrance and the hydrogen bonding from the agarose network effectively limit the migration of the Fe304@SiO2 particles and their chain-like assemblies. As a result, the system shows remarkable stability in photonic response under external magnetic fields of large gradients, something which has previously been a challenge. The ability to stabilize the magnetic particle assemblies over a long period represents a major stride toward practical applications of such field- responsive photonic materials.

Highly active CeO_2 hollow-shell spheres with Al doping

Metal oxide hollow structures are of great inter- est in many current and emerging areas of technology. This paper presents a facile and controlled protocol for the syn- thesis of Al-doped CeO2 hollow-shell spheres （CHS）, where the dopant confers enhanced stability and activity to the ma- terial. These Al-doped CeO2 hollow-shell spheres （ACHS） possess a controllable shell number of up to three, where the sizes of the exterior, middle, and interior spheres were about 250-100 nm,150-50 nm, and 40-10 nm, respectively, and the average shell thickness was -15 nm. The thermal stability of the ACHS structure was enhanced by the homogeneous in- corporation of AI atoms, and more active oxygen species were present compared with those in the non-doped congener. Au NPs supported on ACHS （Au/ACHS） showed superior cat- alytic performance for the reduction of p-nitrophenol. For the same Au NP content, the reaction rate constant （k） of the Au/ACHS was nearly twice that of the non-doped Au/CHS, indicating that AI doping is promising for improving the per- formance of inert or unstable oxides as catalyst supports.

Exponential Stability Analysis of a Markovian Deteriorating System

The reliability of a complex system passes through a gradual deterioration until at some critical level, the system fails completely. The study of the exponential stability of such a system requires the application of functional analysis and, particularly, the theory of linear operators in Banach space to demonstrate the existence of strictly dominant eigenvalue. Through analyzing the variation of the essential spectral radius of semigroups before and after perturbation, it is shown that the dynamic solution of the system converges to the steady-state solution of the system exponentially under certain condition.

PbCrO_4 yellow-pigment nanorods: An efficient and stable visible-light-active photocatalyst for O_2 evolution and photodegradation

Here, PbCrO4 nanorods, a commonly used and low-cost yellow pigment, was synthesized via a simple pre-cipitation reaction and can serve as a highly efficient oxygen production and photodegradation photocatalyst. The obtained PbCrO4 nanorods exhibit excellent stability and pho-tocatalytic performance for O2 evolution from water. The production rate is approximately 314.0μmol h^-1 g^-1 under visible light, and the quantum efficiency is approximately 2.16% at 420±10 nm and 0.05% at 600±10 nm. In addition, the PhCrO4 shows good degradation performance for methylene blue, methyl blue, methyl orange and phenol under visible-light irradiation. These results indicate that it is potential to fabricate an effective, robust PbCrO4 photocatalyst by trans-forming heavy-metal pollutants Pb（II） and Cr（VI） into a highly efficient O2 evolution and photodegradation material. This strategy which uses pollutant to produce clean energy and degrade contaminants is completely green and environmentally benign, and thus could be a promising way for practical environmental applications. Keywords： 02 evolution, pollutant, PbCrO4 nanorods, visible-light-active, photocatalyst

Self-assembled multifunctional Fe_(3)O_(4) hierarchical microspheres: high-efficiency lithium-ion battery materials and hydrogenation catalysts

Self-assembled Fe_(3)O_(4)hierarchical microspheres(HMSs) were prepared by a one-pot synchronous reduction–self-assembling (SRSA) hydrothermal method.In this simple and inexpensive synthetic process,only glycerol,water,and a single iron source (potassium ferricyanide (K3[Fe(CN)6]))were employed as reactants without additional reductants,surfactants,or additives.The iron source,K3[Fe(CN)6],and glycerol significantly affected the synthesis of Fe_(3)O_(4)HMSs.Fe_(3)O_(4)HMSs with a self-assembled spherical shape readily functioned as high-performance anode materials for lithiumion batteries with a specific capacity of>1000 mA h g^(-1)at0.5 A g^(-1)after 270 cycles.Further charging and discharging results revealed that Fe_(3)O_(4)HMSs displayed good reversible performance (>1000 mA h g^(-1)) and cycling stability (700 cycles) at 0.5 A g^(-1).Furthermore,as multifunctional materials,the as-obtained Fe_(3)O_(4)HMSs also exhibited high saturation magnetization (99.5 emu g^(-1)) at room temperature (25°C) and could be further employed as efficient and magnetically recyclable catalysts for the hydrogenation of nitro compounds.

Spectroscopic and electrochemical properties of Cu-dicyandiamide complex

Dicyandiamide(DICY) is a common ligand that exhibits low toxicity but can irritate the skin and eyes and cause methemoglobinemia on long-term exposure. Crystalline Cu-dicyandiamide(Cu-DICY) was obtained via facile synthesis and its molecular structure and theoretical Raman spectra were simulated by using density functional theory(DFT). The results suggested that the Cu^(2+) coordinates with two H_2 O molecules and two different DICY molecules(an imino DICY and an amino DICY). The stability constants of Cu-DICY were calculated, and the electrochemical properties were studied. Two electrochemical redox processes occur in Cu-DICY in an aqueous solution: a reversible reaction with a formal potential of 0.2 V vs.MSE and an irreversible reaction between –0.4 and –1.2 V vs. MSE. The standard rate constant k0 for the reversible reaction was estimated to be 7.6×10^(-3) cm/s. In addition, based on the reversible reaction of Cu-DICY, square wave voltammetry was used to rapidly determine the concentration of Cu(II) and the detection limit was 66.7 μg/L, which satisfies the detection limit requirements for copper in tap water(2 mg/L) as provided by the World Health Organization.