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[en] Using a 48.6 GeV polarized electron beam scattering off a polarized 3He target at Stanford Linear Accelerator Centre (SLAC), they measured the neutron spin structure function g1n over kinematic(x) ranging 0.014 < x <0.7 and 1 < Q2 < 17GeV2. The measurement gave the integral result over the neutron spin structure function ∫0.0140.7 g1n(x)dx = -0.036 ± 0.004(stat) ± 0.005(syst) at an average Q2 = 5GeV2. Along with the proton results from SLAC E143 experiment (0.03 < x) and SMC experiment (0.014 < x < 0.03), they find the Bjorken sum rule appears to be largely saturated by the data integrated down to x of 0.014. However, they observe relatively large values for g1n at low x. The result calls into question the usual methods (Regge theory) for extrapolating to x = 0 to find the full neutron integral ∫0t g1n(x) dx, needed for testing the Quark-Parton Model (QMP)
[en] This patent describes a process for moving an article at a velocity in excess of 10 Kilometers per second. It comprises providing a contactless, mass transfer system comprised of a chamber formed by alternating sections of superconductive material and electromagnetic coils, and means for cooling the chamber; providing a magnetized object which has a weight of at least about 1 gram and a magnetic field strength of at least about 1 Gauss; disposing the magnetized object within the chamber; delivering asynchronous direct current pulses to the chamber while the magnetized object is disposed within the chamber; whereby the magnetized object is caused to move within the chamber
[en] The ethanolic extracts of some Chinese traditional herb drugs, reported by Hong-Fu Wang et al. in China, could inhibit platelet aggregation as well as protect against radiation damage in mice, rat and rabbits. The inhibitory effects of the extracts of five Chinese drugs on the rate of platelet aggregation were observed in both in vitro and in vivo tests, averaging 23--53% in vitro and 46--69% in vivo. Antiradiation tests on mice vs. 7.5--8.0 Gy of γ-radiation, using the herb drug extracts as protective agents, showed increasing survival rates by 8--50%. Based on Hong-Fu Wang's report, a search for the active constituents of these herb drugs in inhibiting platelet aggregation and protecting animals against radiation damage was started. In this research program, a Chinese traditional drug, Rhizoma Chuanxiong (rhizome of Ligusticum chuanxiong Hort.) was chosen. Three types of chemicals present in Rhizoma Chuanxiong, appeared promising for testing: 1-(5-hydroxymethyl-2-furyl)-9H-pyrido-(3,4-b)indole, 4-hydroxyl-3-butylidenephthalide and 5-hydroxyl-3-butylidenephthalide, and 4-hydroxyl-3-methoxycinnamyl 4-hydroxyl-3-methoxycinnamate. A total of 56 compounds of these derivatives has been synthesized and 30 were synthesized for the first time. The structure elucidation of these compounds was based on IR, 1H NMR and elemental analysis. From this research program, a very mild dehydrogenation method was developed. It was by using 2,3-dichloro-5,6-dicyanobenzoquinone in acetonitrile at ice bath temperature to dehydrogenate 1-(5-hydroxymethyl-2-furyl)-1,2,3,4-tetrahydro-9H-pyrido-(3,4-b)indole into 1-(5-hydroxymethyl-2-furyl)-9H-pyrido-(3,4-b)indole. This project showed for the first time that harmanoid alkaloids have the activity of inhibition of plate aggregation by 4 to 23 times that of aspirin. These results aid in establishing a relation between radiation protection in animals and prevention of platelet hyperaggregation
[en] SMR is one of the hot research and development direction because of its high safety, low initial investment and multi-function characteristics. With the support of the Chinese government, a number of Chinese nuclear power groups are developing SMR including CAP200, ACP100, NHR200-II and ACPR50 which advantages have been verified. In future, regulatory standards, modular construction and economic upgrading of SMR will still be hot research directions in China.
[es]Los SMR es una de las líneas de investigación y desarrollo más novedosas debido a su alta seguridad, baja inversión inicial y características multifuncionales. Varias empresas chinas, con el apoyo del Gobierno chino, están desarrollando diseños SMR incluyendo CAP200, ACP100, NHR200-II y ACPR50 cuyas ventajas frente a otros diseños han sido verificadas. En el futuro, las normas reguladoras, la construcción modular y las mejoras económicas de los SMR seguirán siendo algunas de las principales líneas de investigación en China.
[en] An investigation is carried out to understand hydrothermal effects on locally delaminated buckling near the surface of a cylindrical laminated shell. The delamination shape is considered as a rectangle. The sub-laminated shell is taken as monolayer or multilayer. The stacking sequence of sub-layers may be asymmetric. The effect of non-linear buckling for local delamination of cylindrical laminated shells is obtained by considering transverse displacements of the sub-laminated shell. The Young's modulus and the thermal and humidity expansion coefficients of the material are treated as functions of temperature change in base laminated shells. The critical strains of cylindrical laminated shells with various hydrothermal environments, different stacking sequences and different radii of the cylindrical laminated shells are obtained by means of the energy principle. From example calculations, it is found that the non-linear solution of critical buckling for local delamination near the surface of a laminated cylindrical shell under a hydrothermal environment gives a lower value than that from linear analysis
[en] In the past decade, collaborations between China and European Union have been rapidly expanding. Hitherto, however, little research has been carried out to assess implementation and impacts of such collaborations. This paper evaluates the collaboration performance between China and the EU28 concerning major research and innovation priorities. To shed light on the initiatives of collaborations, corresponding authors are detected and classified into three categories, Chinese local, Chinese abroad, and non-Chinese. In order to foster more profitable collaboration for both parties and to formulate options for international policy on research and innovation cooperation between the European Union and China, this paper presents an in-depth analysis of the scientific collaborations focusing on the initiatives and benefits of the collaborations. (Author)
[en] The domain formation and structures in a ferroelectric tetragonal model system in which the dipole-dipole interaction and gradient domain wall energy are taken into account is studied using Monte-Carlo method. It is revealed that the 90 deg. -domain walls with preferred head-to-tail dipole alignment coexist with the 180 deg. -walls in the domain configuration. The dipole-alignment patterns at various temperatures and system parameters are investigated, indicating clearly the suppression in magnitude of dipoles on the domain walls in order to lower the system free energy. The effect of temperature and gradient wall energy on the hysteresis loop is also simulated
[en] We present the expressions of nonlinear effective susceptibilities of antiferromagnetic/nonmagnetic superlattices with an effective-medium method, and then on this basis investigate nonlinear dispersion properties of antiferromagnetic polaritons in the superlattices. In the geometry used in the paper, the y-axis is normal to the interface, and the z-axis is pointed along the anisotropy axis. The theoretical analysis and numerical calculations show: (i) The nonlinearity has no contributions to the waves traveling along the three axes, and to the waves in the x-y plane. (ii) The nonlinear shift in wave number is either upward or downward, depending on the mode frequency larger or less than the resonance frequency, for the wave traveling along the other directions
[en] This paper presents the weight functions for the determination of the stress intensity factor and T-stress solutions for edge-cracked plates with built-in ends under complex stress distributions. First, a compliance analysis approach is used to calculate stress intensity factor and T-stress for edge cracks in finite width plates with built-in ends with uniform or linear stress distributions acting on the crack face. The results serve as the reference solutions for the next step in which the approaches of deriving weight functions from reference stress intensity factor and T-stress solutions developed for stress boundary conditions are extended to obtain the corresponding weight functions for edge-cracked plates with built-in ends. Finite element analysis is conducted to validate the derived solutions. The weight functions derived are suitable for obtaining stress intensity factors and T-stress solutions under any complex stress field
[en] The APS system will contain three rings. The first is a positron accumulator ring (PAR). Its function is to coalesce 24, 30-ns-long positron bunches into one 290-ps bunch. The second is the injector synchrotron (IS). It accelerates the 450-MeV positron bunches to 7 Gev for injection into the storage ring (SR). Betatron and synchrotron motion frequently occurs in circular machines, without any deliberate excitation. However, the amplitudes of this motion cannot be predicted. Therefore, it is desirable to have controlled ways to excite these modes. Two types of devices will be used to excite the beam. One will be a magnetic kicker or bumper. All rings already have these devices planned for the horizontal direction for injecting and extracting beams. Some of these magnets will be used for exiting horizontal betatron motion. In the storage ring, a special kicker will be installed to produce up to 1 mm amplitude motion in the vertical direction. Two 8.4-in striplines (SL) (1/4 wavelength at 352 MHz) will be installed on all rings. One stripline in each ring will be used to drive all three tunes, and the other stripline will be used as a pickup. In the PAR and IS, the pickup stripline will be in a dispersive region. This will allow observation of both betatron and synchrotron motions. In the SR, the stripline will be in a nondispersive region because it is not practical to install it in a dispersive region. To do synchrotron tune measurements in the SR, one of the button BPMs located in a dispersive region will be used. To minimize development effort, as much of the BPM system electronics as possible will be used in the tune measurement system. The BPM electronics uses the AMP/PM conversion technique. This system operates at 352 MHz. Thus, tune measurement components were also designed to operate at 352 MHz