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Many lighting energy-saving modification programs have the embarrassment of uneconomical. Th is paper takes into account economic evaluation to solve the problem. According to illu minative equip ments price, life span and power consumption, the optimal program will be found under the limited investment. Firstly, the benefit ratio will be used to evaluate on the equipments modification necessity, and get the modification sequence. If the b iggest benefit ratio is in different equip ment simu ltaneously, the better one will be selected in terms of relat ive investment recovery period. The relat ive remaining t ime is innovatively introduced into economic evaluation for determining the equip ments modification locations. Then the system operation flowchart is to prove that the scheme is workable.

Cyclic voltammetry and in situ Raman spectroscopy were used to determine the adsorption mechanism of nicotinic acid onto passive iron film surface. Its ability to form a surface complex tends to stabilize the interstitial Fe-II in Fe-III states and results in the progressive development of an insoluble film. Furthermore, an analytical investigation using a rotating electrochemical quartz crystal microbalance (rEQCM) showed that the adsorption isotherms of nicotinic acid onto iron in the active and passive states followed Langmuir-Freundlich behavior from which the adsorption constant, standard free energy of adsorption, and heterogeneity could be calculated. The organic molecules attach to the film surface by chemisorption and the interstitial cations are fixed in the octahedral sites giving stable nanocrystals. These assumptions were confirmed by scanning electron microscopy (SEM) and attenuated total reflection transform infrared (ATR FTIR) spectroscopy.

A high efficiency 2D percolation model of RTS amplitudes in nanoscale MOSFETs based on the numerical results of potential and carriers density distributions in the channel obtained by solutions of coupled 2D Schrodinger and Poisson equations was presented. Using this model the dependences of relative RTS amplitudes Δ I D / I D on device geometry L eff × W eff , t ox bias conditions I D , V G and trap locations along the channel were simulated and analyzed for a set of square n-MOSFETs. The results show reasonable agreement with published numerical or experimental data.

Magnetic bunch compressor is one of the key technologies on the path to next generation accelerator driven facilities. In this paper we report the design principles and the first experimental research of the bunch compressor developed at Chinese Academy of Engineering Physics (CAEP). The length of the bunch after compressor is found to be about 0.7 ps (rms) and the peak current exceeds 500 A when operated in the optimized condition. The sensitivity of the bunch length on the phase of the acceleration field and magnetic field of the bunch compressor was also measured and analyzed.

Dithio-N,N'-dimethoxypropyldipropionamide (DPDA) was investigated as a corrosion inhibitor for Mild steel in 1 mol.L-1 hydrochloric acid using weight loss test, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), quantum chemical study, and Raman spectroscopy. The weight loss test results showed that DPDA was an excellent inhibitor for mild steel in acid media with an inhibition efficiency of 90.2% at the DPDA concentration of 1x10-3 mol.L-1. The polarization curves indicated that DPDA behaved as a mixed-type inhibitor while the single capacitive loop in the Nyquist plots revealed that the corrosion was a charge transfer controlled process. Inhibition efficiencies increased with the increase of DPDA concentrations, and the values of the inhibition efficiencies, obtained from the weight loss test, potentiodynamic polarization, and EIS, were in reasonable agreement. The absorption of DPDA was found to obey the Langmuir adsorption isotherm. The free energy of adsorption (Delta G(ads)(0)) was found to be -38.65 kJ.mol(-1) and this value indicated that the adsorption was mainly chemisorption. This results from the sharing or/and transfer of electrons from the DPDA molecules to the metal surface to form coordinate bonds. The negative Delta G(ads)(0) value revealed that the adsorption of DPDA was a spontaneous process. Raman spectra suggest that DPDA adsorbed well onto the mild steel surface, and the quantum chemical study showed that the sulphur atoms in the DPDA molecule were the main active sites that resulted in absorption on the surface of the mild steel.

The experiment was conducted to investigate continuous hydrogen production with lower cost and sulphate-rich wastewater treatment. In this paper, both anaerobic bio-treatment of sulphate-rich wastewater and hydrogen production were applied to construct a laboratory-scale combined sulphur cycle based system. The system consisted of two reactors, which were a photocatalytic reactor and an anaerobic bioreactor, respectively. In the anaerobic bioreactor, sulphate-reducing bacteria (SRB) converted SO4(2-) to S(2-). The produced S(2-) yielded by SRB was further used as a sacrificial reagent to produce H2 in the photocatalytic reactor. Then, S(2-) was changed into SO4(2-), which returned to the anaerobic bioreactor for treatment again. The present study highlighted an advantage compared with the conventional method, in that no extra S(2-) was added to the photocatalytic reactor, which reduced the total cost and realized continuous hydrogen production. The average COD removal efficiency was 79.6%.

Diffraction radiation is one of the most promising candidates for electron beam diagnostics for the International Linear Collider, x-ray free electron lasers and energy recovery linac due to its non-intercepting characteristics. We report the non-intercepting measurement of sub-ps electron bunch length with coherent diffraction radiation. The bunch length is measured with a Martin—Puplett interferometer and the detailed longitudinal bunch shape is reconstructed with the Kramers—Kronig relation. The rms bunch length is found to be about 0.73 ps, which confirms a successful commissioning of the bunch compressor and the interferometer.

The dynamics of two confined colloidal particles is studied by means of Brownian dynamics simulation. The autocorrelation function and cross-correlation function of the two colloidal spheres are computed by utilizing the formulae of hydrodynamic diffusion matrix expanded to different orders, as well as the accurate tensor through numerical algorithm. Furthermore, the numerical results are compared with the experimental results and the theoretical approximation. It is found that the relatively simple theoretical approximation gives good predictions when two spheres are far away from each other, but fails when the two spheres are very close.

To deal with pattern classification of complicated mechanical faults, an approach to multi-faults classification based on generalized discriminant analysis is presented. Compared with linear discriminant analysis (LDA), generalized discriminant analysis (GDA), one of nonlinear discriminant analysis methods, is more suitable for classifying the linear non-separable problem. The connection and difference between KPCA (Kernel Principal Component Analysis) and GDA is discussed. KPCA is good at detection of machine abnormality while GDA performs well in multi-faults classification based on the collection of historical faults symptoms. When the proposed method is applied to air compressor condition classification and gear fault classification, an excellent performance in complicated multi-faults classification is presented.

A new semianalytical method, which is a combination of the density functional theory with Rosenfeld density functional and the Ornstein–Zernike equation, is proposed for the calculation of the effective depletion potentials between a pair of big spheres immersed in a small hard sphere fluid. The calculated results are almost identical to the integral equation method with the Percus–Yevick approximation, and are also in agreement well with the Monte Carlo simulation results.

Using the decimetric (700-1500MHz) radio spectrometer and the synchronous observational system with high temporal resolution at four frequencies (1420, 2130, 2840 and 4260 MHz) of Yunnan Observatory, two rare events were observed on 2001 June 24 and 1990 July 30. The former was a small radio burst exhibiting pulsations with short periods (about 29, 40 and 100 ms) in the impulsive phase. The latter was a large radio burst, which at 2840 MHz produced radio pulsations with period of about 30 ms. This paper focuses on pulsations with very short periods in the range of 29-40 ms. The mechanism of generation of such pulsations may be modulation of radio radiation by the periodic trains of whistler packets originating in unstable regions of the corona. Alternatively, these pulsations can be attributed to wave-wave non-linear interactions of electrostatic upper hybrid waves driven by beams of precipitating electrons in flaring loops.

On 1998 September 23, a rare event was observed with the microwave (1.0-2.0 GHz and 2.6-3.8 GHz) radio spectrograph of National Astronomical Observatories. It was a complex type-IV burst accompanied by multi-periodic pulsations, type-III bursts and type-I like noise storms. This paper focuses on the pulsation components with multiple long periods (about 7.3, 4.9, 3.7, 1.2 and 0.4 minutes). The pulsations may be due to standing waves in closed loops. Magnetohydrodynamic standing Alfven waves driven by the photospheric velocity field penetrate across the magnetic field, and this leads to the modulation of the radio radiation. These pulsations have downward motions, so it is not excluded that disturbances propagating in a closed or an open field structure may have caused the pulsations. The resonance of Alfven waves is concerned with the photospheric 5-minute oscillations, hence pulsations of very long periods may be assumed to come from driving sources in the photosphere. This can imply a possible mutual coupling between coronal magnetic loops and the photosphere.

One component hard-sphere fluid confined in two planar hard walls is studied by means of density functional theory with Rosenfeld functional and molecular dynamics simulation. The validity of the Rosenfeld functional is examined. Chemical potential, grand potential and free energy as functions of the wall separation are obtained.