俄罗斯第五代战机呼之欲出“苏霍伊”与“米格”:两大公司的研制之争

据俄罗斯媒体报到，继去年10月美国的洛克希德·马丁公司击败实力强劲的飞机制造业巨擘波音公司，夺得五角大楼2000亿美元新型联合攻击机订货合同之后．近日俄罗斯也将上演一场“龙虎斗”。俄罗斯著名的两家战斗机设计局——“苏霍伊”和“米格”设计局将为争夺俄制第五代战斗机的研制权展开激烈竞争。

米格25叛逃记

这一年，第二次世界大战后的军备竞赛，突然进入一个高潮，因为苏联空军王牌战机——“米格”25落入了西方国家的手中。1976年9月6日，日本时间下午1时11分。日本防卫机构的雷达系统，发现在涵馆西北约300公里的日本海上空，有一架来历不明的、不明国籍的飞机。5分钟后，位于北海道的千岁空军基地，派出两架F-4EJ“幽灵”战斗机，进行空中拦截。

1-2000——21世纪初俄罗斯的主力战斗机

面对美国咄咄逼人之势。为证实自己足以研制出与美国先进武器抗衡的实力，俄罗斯突然公布MFI重型战斗机和针对美国JSF“联合攻击战斗机”的LFI轻型战斗机，即“米格”Ⅰ-2000。

Velocity of a Liquid Drop with a Sorption-Controlled Surfactant

The terminal velocity of a liquid droplet settling in a sulfactant solution has been studied for the non-linear adsorption Langmuir frameworks accounting for monolayer saturation and non-ideal surfactant interactions. Most prior research uses a linear adsorption model which cannot capture these effects, The Maragoni migration of a liquid drop settling through a surfactant solution is examined by using Langmuir framework. The solution concentration Ceq is assumed large enough for the surfactant mass transfer to be adsorption-controlled. Langmuir model generates non-linear Marangoni stresses which diverge in the limit of approaching ∝, strongly retarding U'.

Epitaxial Growth and Thermoelectric Measurement of Bi2Te3/Sb Superlattice Nanowires

Superlattice nanowires are expected to show further enhanced thermoelectric performance compared with conventional nanowires or superlattice thin films. We report the epitaxial growth of high density Bi2Te3/Sb superlattice nanowire arrays with a very small bilayer thickness by pulse electrodeposition. Transmission electron microscopy, selected area electron diffraction and high resolution transmission electron microscopy were used to characterize the superlattice nanowires, and Harman technique was employed to measure the figure of merit （ZT） of the superlattice nanowire array in high vacuum condition. The superlattice nanowire arrays exhibit a ZT of 0.15 at 330 K, and a temperature difference of about 6.6 K can be realized across the nanowire arrays.

共和国航空事业的重要奠基人和开拓者-访中国空军第一师首任师长方子翼

中国空军伴随着共和国前进的步伐，现已经发展成为一支强大的空中力量。当年中国空军成立刚刚一年，前辈们就和苏联空军一起翱翔于朝鲜半岛上空，在鸭绿江和青川江之间开辟了著名的“米格走廊”。回顾人民空军走过的不平凡之路，在中国空军的史册上。方子翼这个名字格外引人注目，他从红军到新疆航空学校第三期飞行班第一个单飞上蓝天；从东北老航校第一飞行大队政委到新航校第五航校校长；从空军11团团长，空3旅旅长到空1师首任师长。在抗美援朝战争中，他受命率先出征，

An Empirical Study on the Relationship Between China's Maize Price and Maize Import and Export Trade

Based on the time series of China’s maize trade and domestic maize price,the article analyzes the relationship between domestic maize price and China’s maize international trade by using empirical methods.The results show that there is a connection between domestic maize prices and China's maize international trade,but the link is not very close.Domestic maize price is the cause of China’s maize international trade change,but its impact is very limited;China's maize international trade also can make some difference on the domestic maize price.Based on the results of research,the article brings three suggestion and expectation to adjust China’s maize international trade and the cost control reasonably in order to stabilize domestic maize price and maize yield,and to protect domestic grain security.

Brightening of Dark Excitons in Single-Walled Carbon Nanotubes:Investigation by Many-Body Green’s Function Theory

Optical excitations of the hybrids,which are assembled by coupling single-walled carbon nanotubes(SWCNTs)with organic molecules through van der Waals interactions,are studied using ab initio manybody Green’s function theory.We take the semiconducting(7,0)SWCNT,the squarylium and oligothiophene molecules as the example.The E11 and E22 absorption peaks of the(7,0)tube can be redshifted by tens of meV.Most importantly,the lowest dark exciton of the(7,0)tube at the lower-energy side of E11 can be brightened by the interaction between the nanotube and molecules.Position of this new satellite absorption peak is influenced by the type of adsorbed molecule.These findings may be useful for tuning the emission energy and emission efficiency of CNTs.

Design and Manufacture of GeSi/Si Superlattice Nanocrystalline Photodetector

According to Maxwell’s theory, the optical transmission characteristics in GeSi/Si superlattice nanocrystalline layer have been analyzed and calculated. The calculated result shows that when the total thickness L is 340nm, the single mode lightwave can be transmitted only at periodic number M≥15.5. In addition, at the direction of transmission, when the transmission distance is larger than 500μm, the lightwave intensity is decreased greatly. Based on the above parameters, the design and manufacture of GeSi/Si superlattice nanocrystalline photodetector are carried out.

Structure Determination of By-product in Grignard Reaction for Preparing Mifepristone Derivatives

Aim To determine the structure of the by-product produced in Grignard reaction for preparing mifepristone derivatives, and elucidate the reaction mechanism.Methods The structure of the by-product was determined with elemental analysis, one- and two-dimension spectra NMR (DEPT, 1H-1Hcosy, HMQC, HMBC) and compared with those of mifepristone.Results The main by-product was 11,17-di-addition product of Grignard reagent of N, N-dimethylamino phenyl bromide.Conclusion This is the first complete assignment of 1H NMR and 13C NMR of compound (3).

Unconventional Landau Levels of Ultracold Fermionic Atoms on Two-Dimensional Honeycomb Lattice

We investigate the unconventional Landau levels of ultracold fermionic atoms on the two-dimensionalhoneycomb optical lattice subjected to an effective magnetic field,which is created with optical means.In the presenceof the effective magnetic field,the energy spectrum of the unconventional Landau levels is calculated.Furthermore,wepropose to detect the unconventional Landau levels with Bragg scattering techniques.

Efficiency Improvement of 590 nm AIGalnP Light Emitting Diode with a Reflective Top Electrode

In this work, enhancement of the light extraction efficiency of a 590 nm AIGaInP light-emitting diodes （LED） with a reflective top electrode （RTE） was investigated. A distributed Bragg reflector （DBR）, consisting of AIAs/AIGaAs pairs, grown on an AlGaInP structure was used as a reflector for a reflective top electrode. It was found that a higher output power was observed from the AIGalnP LED with a RTE than from a conventional one. In addition, it was noted that the improvement in the output power depends strongly on the reflectivity of the reflector and that it exhibits a more effective performance with low injection currents. The increase in the optical output power was attributed to the enhanced extraction efficiency caused by a reduction of light absorbed from the emission region to top electrode through the RTE.

Study of Topological Structure of Vacuum by Lattice QCD

Overlap fermions and improved 5Li cooling are compared, which exhibits that these two filter methods can produce similar structures. Then the overlap fermions and improved 5Li cooling are combined to calculate the topological charge and identify the structure of the vacuum. The results are consistent with instanton liquid model .

Liberalization of Staple Crops： Lessons from the Mexican Experience in Maize

In this paper the authors inquire why, after more than 25 years of domestic agricultural reforms in Mexico and 15 years of trade liberalization of maize under the North American Free Trade Agreement （NAFTA）, the domestic production of maize, a non-competitive crop and the major staple in Mexico, has increased. The authors present new empirical evidence showing that, as expected, maize prices in Mexico dropped until 2006 and have experienced a process of convergence with USA prices, and maize imports from the USA have increased. However, despite lower prices, maize production in Mexico has trended upward since 1992, two years before the beginning of NAFTA＇s implementation. Based on the heterogeneity of maize production in Mexico, three possible explanations are proposed to explain this unexpected outcome： government supports to big commercial farmers in the agriculturally rich North of Mexico; the persistence of maize production by subsistence farmers; and to a lesser degree, increasing yields on some irrigated maize farms. We finish the paper by drawing lessons from the experience of Mexico for other Less Developed Countries.

Comparative Analysis of Household Consumption Pattern of Local and Imported Rice in Ekiti State, Nigeria

The paper examined the consumption pattern and attitude of households for local and imported rice in Ekiti State, Nigeria. The specific objectives of the paper are to： examine the household preference and consumption level of local and imported rice, examine price variation between local and imported rice and identify the major problems confronting marketers of local and imported rice. Data were collected from 100 randomly chosen households with the aid of structured questionnaire. Data collected were analyzed with the use of descriptive statistics such as frequency, percentages, chi-square, t-test and regression analysis. The paper revealed among others that majority of the respondents prefer to consume local rice to imported rice because of its more palatability, health benefits, readily availability and relatively cheap price. The average price per kilogramme of local rice is 200 Naira compared to that of imported rice which is 300 Naira. The difference in price is as a result of exchange rate and costs associated with smuggling of imported rice across the border of Nigeria from neighbouring countries. Nonetheless, the quality of local rice is still very low when compared to imported rice in terms of degree of impurities such as stone and shafts and the level of polishing.

Lattice QCD Calculation of ππ Scattering Length

We study s-wave pion-pion scattering length in lattice QCD for pion masses ranging from 330 MeV to 466 MeV. In the ＂Asqtad＂ improved staggered fermion formulation, we measure full ππ four-point correlators for isospin I = 0 and 2 channels, and use chiral perturbation theory at next-to-leading order to extrapolate our simulation results. Extrapolating to the physical pion mass yields scattering lengths as mna01=2 = -0.041 6（2） and mna01= 0.186（2） for isospin I = 2 and 0 channels, respectively. Our lattice simulation for ππ scattering length in I = 0 channel is an exploratory study, where we include the disconnected contribution, and our preliminary result is near to its experimental value. These simulations are carried out with MILC 2 ＋ 1 flavor gauge configurations at lattice spacing a ≈0.15 fm.

International Price Shocks Transmission： The Case of Rice in Togo

The objective of the paper was to examine the relationship between the world rice price and the rice price in Togo using the linear and nonlinear co-integration tests. The author used the monthly prices for Togo local rice market and international market. The results show that the rice prices on the local market are integrated to international market. The elasticity of the long-term transmission is high. The threshold autoregression （TAR） model reveals an asymmetric transmission with a magnitude that varies depending on the nature of shock. Price increases in international markets are transmitted more rapidly to the local markets than price reductions. These results might be explained by the market power of traders, transport costs and government intervention.

Adaptive Lagrange finite element methods for high precision vibrations and piezoelectric acoustic wave computations in SMT structures and plates with nano interfaces

This paper discusses the validity of (adaptive) Lagrange generalized plain finite element method (FEM) and plate element method for accurate analysis of acoustic waves in multi-layered piezoelectric structures with tiny interfaces between metal electrodes and surface mounted piezoelectric substrates. We have come to conclusion that the quantitative relationships between the acoustic and electric fields in a piezoelectric structure can be accurately determined through the proposed finite element methods. The higher-order Lagrange FEM proposed for dynamic piezoelectric computation is proved to be very accurate (prescribed relative error 0.02% - 0.04% ) and a great improvement in convergence accuracy over the higher order Mindlin plate element method for piezoelectric structural analysis due to the assumptions and corrections in the plate theories.The converged lagrange finite element methods are compared with the plate element methods and the computedresults are in good agreement with available exact and experimental data. The adaptive Lagrange finite elementmethods and a new FEA computer program developed for macro- and micro-scale analyses are reviewed, and recently extended with great potential to high-precision nano-scale analysis in this paper and the similarities between piezoelectric and seismic wave propagations in layered structures and plates are stressed.

A Verifiable Multi-Secret Sharing Scheme Based on Hermite Interpolation

A threshold scheme, which is introduced by Shamir in 1979, is very famous as a secret sharing scheme. We can consider that this scheme is based on Lagrange＇s interpolation formula. A secret sharing scheme has one key. On the other hand, a multi-secret sharing scheme has more than one key, that is, a multi-secret sharing scheme has p （〉_ 2） keys. Dealer distribute shares of keys among n participants. Gathering t （〈 n） participants, keys can be reconstructed. Yang et al. （2004） gave a scheme of a （t, n） multi-secret sharing based on Lagrange＇s interpolation. Zhao et al. （2007） gave a scheme of a （t, n） verifiable multi-secret sharing based on Lagrange＇s interpolation. Recently, Adachi and Okazaki give a scheme of a （t, n） multi-secret sharing based on Hermite interpolation, in the case ofp 〈 t. In this paper, we give a scheme ofa （t, n） verifiable multi-secret sharing based on Hermite interpolation.

幻影与米格之战

友军的“幻影”飞机正在攻击敌人的地面目示，我在上空负责警戒。突然，有2架米格-21飞机向友机后方扑去，双方相距1,000米。见情况危急，我立即向编队长机报告，并打开加力驾驶“幻影”ⅢCJ向敌机冲去。几乎是与此同时，编队长机也向敌机冲去。我的目标是右面的米格机，长机对付左面的那架。当我们接近距敌机300米时，2架米格机慌忙丢开目标，转弯解散编队。敌机发现了我们！