EIS studies the effect of Zinc to Al-Zn alloy used for cathodic protection in 3% NaCl solution

Electrochemical impendence spectroscopy （EIS） is applied to investigate the dissolution behavior of Al-Zn alloys in 3% NaCl solution at different polarization potentials. A new reaction model is proposed, and the activation mechanism of zinc in Al-Zn alloys is achieved. There are three intermediates in the dissolution process： Znad^＋, Znad^2＋ and Alad^＋, ,of which only Zni can activate Al-Zn alloys. Most Znnd^＋ is produced by β-phase,and the alloys with 2. 3% - 3. 8% （wt） Zn dissolve rapidly. The Al-Zn alloys of heart-shaped EIS are active in 3% NaCl solution, thus EIS characteristic can be used to distinguish the activa-tion of Al-Zn alloys.

工业平缝机刺布挑线机构的平衡优化设计

随着科学技术的发展,工业缝纫机日益向高速、高效、精密和自动化等方向发展.为了满足内部结构静动态特性的要求,针对高速工业平缝机中产生振动的关键机构——刺布挑线机构,应用复矢量法推导出了该机构的总质心轨迹方程以及总惯性力方程,并通过平衡分析对零件进行了结构优化,还使用MATLAB对优化前后的机构进行了对比分析从而证明该优化方案的可行性.优化结果表明,该优化方法部分地平衡了刺布挑线机构在高速运转中所产生的强惯性力,有效地改善了高速平缝机整机的动态性能.

GA747剑杆织机织造玻纤无捻粗纱方格布的研究

通过对GA747剑杆织机的引纬机构、边剪机构、送经机构、卷取机构进行研究与改造,使GA747剑杆织机不仅能织造玻璃纤维有捻薄布,还能织造玻纤无捻粗纱方格布。通过研究与改造,提高了GA747剑杆织机设备利用率,降低了生产成本,拓宽了可用玻璃纤维品种范围,实现了一机多品种织造工艺技术要求。

Study on the focal mechanism of the M5. 1 Badong earthquake in Hubei

The focal mechanism solutions of the MS. 1 Badong earthquake and subsequent 34 aftershocks at ML 2.0 or more were calculated using the P-wave first motion method; the main earthquake was normal fault dip slip type, and the slip types of the seismogenic rupture surfaces of the subsequent aftershocks primarily include normal dip slip （14 times）, reverse dip slip （9 times）, normal strike slip （9 times） and reverse strike slip （2 times）. The MS. 1 Badong earthquake activities may be related to the stress adjustment caused by the rise of the groundwater level and the decrease of the frictional resistance between structural planes of rock forma- tions due to the effect of reservoir water penetration, and related to the joint activities of the NE-strike Gaoqiao fault and the near EW-strike Daping fault.

RESEARCH ON DISTURBED MECHANISM OF THERMAL NOISES OF THE SURFACE IN ABRUPT GEOTHERMAL ANOMALY

Geothermal anomaly as a physical phenomenon of an active and latent volca nic area would be well recog-nized,and abrupt geothermal anomaly should also be understood.However,in practical work,thermal infrare d remote sensing techniques are frequently u sed to monitor geothermal flows of th e earth.But then,except for this typ e of thermal source in the surface thermal field,there still exist a lot of noises in th e area where the abrupt geothermal an omaly is generat-ed.By Analyzing the reason,we find t hat it is brought about by the non-bou ndless projection characteristics of objects.These noises may be divided into two c lasses:system noises and random noises.If disturbed noises have comparative sta-ble time sequence law and space sequence law,the noises are called system noises.And because system noises have a certain law,it is easy to remove the n oises.On the contrary,if disturbed noises have not law of time sequence a nd space sequence,the noises are called random noises.The random noises have the character of non-linearity,uncertainty and indeterminism.For this case,this p aper discusses the disturbed mechan ism of these noises as well as how to re move them..

STUDY OF MECHANISM OF RQ EMBRITTLEMENT OF Fe_(73.5)Cu_1-Nb_3Si_(13.5)B_9 NANOCRYSTALLINE SOFT MAGNETIC ALLOY

Rapidly quenching embrittlement (RQE) sometimes appears in nanocrystalline soft magnetic alloy (FINEMET) during production process. As a re-sult of RQE the ductility of the as-quenched ribbon drops seriously. The mechanism of RQE has been elucidated in the recent works of current authors. R was believed that RQE is due to the structural relaxation but not related to α-Fe(Si) crystallization. In this paper, the high resolution TEM (HRTEM) method and image digital processing were applied to analyze the HRTEM images of two FINEMET rapidly quenched ribbons with different thicknesses in detail. In the thinner ductile sample, the ordering domains with the size of about 3nm are observed. In the thicker RQE sample, the metastable nanocrystalline domains with the size of 18nm are observed along with the structural relaxation. These domains seem to have Fe3B-like metastable phase struc-ture on nanometer scale. The result indicates that the local atomic ordering regions extend when RQE induced by structural relaxation occurs.

Research on Control System of Spindle Drive for High Speed Spinning Machine

Through analyzing the principle of spindle drive of winding mechanism for high speed spinning machine,the article not only describes a kind of mode of spindle drive for take-up motion on the basis of control method of constant velocity winding, but also introduces the design technique of software and hardware for the control system of mechatronics of spindle drive mode for take- up motion on the basis of constant velocity winding for high speed spinning machine with single-chip microcomputer. The mathematical model to describe the spindle rotating speed is established. It is an important technology for high speed spinning machine and provides a feasible application way.

Thermal Behavior Study of Carbonate Inorganic Materials

The thermal decomposition processes of（MgCO3）4·Mg（OH）2·5H2O（MCH）,5ZnO·2CO3·4H2O（ZCH）,NiCO3·2Ni（OH）2·4H2O（NCH）,PbCO3（LC）and [Cr（OH）5]2·CO3·8H2O（CC）were studied via TG-DSC.The results of research imply that MCH has the largest capacity of heat absorption and ZCH is second to MCH among the studied materials.The non-isothermal kinetic parameters of MCH and ZCH were calculated by Kissinger and Ozawa methods.Furthermore,thermal decomposition mechanisms of MCH and ZCH were investigated by Coats-Redfern method.Due to the large specific heat capacity,MCH and ZCH are promising to be used as a coolant in extinguishant formulations.

Signaling Pathways and Molecular Mechanisms of Oxidative Stress in Skeletal Muscle

Oxidative stress is a major factor affecting animal health and production performance. This paper briefly introduced the signaling pathways(i.e. NF-κB signaling pathway, MAPK, AP-1 and PGC-1α) of oxidative stress and the main genes regulating the signals of oxidative stress in skeletal muscle, providing a theoretical basis for reducing oxidative stress damage.

Multiwavelength Doppler factors for Fermi-detected gamma-ray loud blazars

We collect a sample of 51 Fermi-detected gamma-ray loud blazars with known radio Doppler factors and study properties of the Doppler factors of blazars at optical, X-ray and gamma-ray bands. A basic assumption is that the emission from the radio to gamma-ray bands of the blazars are produced by the nonthermal radiation of accelerated particles in a jet. Our results show that （1） the Doppler factors of blazars are a function of frequency, with the Doppler factor decreasing with frequency from the radio to X-ray regions, and then increasing from the X-ray to ,y-ray regions which are similar to results given by Zhang et al., and （2） there are marginal correlations between the Doppler factors at radio and X-ray bands and the synchrotron peak fre- quency, and a strong correlation between the Doppler factor in the gamma-ray band and the synchrotron peak frequency, but no correlation in the optical band.

Atomic Diffusion and Electric Conductivity of Gum Arabic/Graphite Composite

In this work, we had adopted solid states reaction kinetic model to calculate diffusion coefficient of graphite Gr in Gum Arabic (GA) as the function of temperatures and concentration? D(t, C). From the calculations we have found that the diffusion coefficient D increases with increasing temperature. At higher temperature the Gr atoms might get enough thermal energy to overcome the activation energy (Ea) barrier and hence can easily be transported to a new atomic position. Diffusion coefficient of Gr at high concentrations had exceeded that at low concentrations by more than two to three orders of magnitude. Such increase can be attributed to the large number of jumps or jump frequency which found to be directly proportion to the Gr concentration. Electric conductivity, calculated by Nernst-Einstein equation, at high concentration Gr had exceeded that at lower concentration. The decrease in conductivity with decreasing Gr concentration might be attributed to the effective charges interactions, which lead to enhance the recombination of charge carriers.

Synthesis, Kinetics and Mechanism of Terpolymerization of Styrene, Vinyl Acetate with Acrylonitrile Initiated by P-Nitrobenzyl Triphenyl Phosphonium Ylide

Synthesis of terpolymers consisting of two electron-donating monomers, viz. styrene and vinyl acetate with one electron-accepting monomer, i.e. acrylonitrile, initiated by p-nitrobenzyl triphenyl phosphonim ylide in dioxane as diluent at 65°C for 150 min has been studied. The kinetic expression is Rpα[I]0.8[Sty] 1.2[VA] 1.4 [AN]1.2. The terpolymer composition was determined by the Kelen-Tüdos method. The values of reactivity ratios using r1 (Sty + VA) = 0.1 and r2 (AN) = 0.005. The overall activation energy is 46 kJ●mol●L–1. The formation of terpolymer is confirmed by the FTIR spectra showing bands at 3030 cm–1, 1598 cm–1, and 2362 cm–1, confirming the presence of phenyl, acetoxy and nitrile group respectively. The terpolymer has been characterized by 1H-Nuclear Magnetic Resonance, 13C-Nuclear Magnetic Resonance. The Differential Scanning Calorimetric curve shows the Tg of the polymer as 149.5°C. A scanning electron microscope confirms the polymer to be phosphorus free. Electron.Spin.Resonance spectra confirms phenyl radical responsible for initiation.

Channel Estimation for One-Bit Massive MIMO Based on Improved CGAN

In the one-bit massive multiple-input multiple-output(MIMO)channel scenario,the accurate channel estimation becomes more difficult because the signals received by the low-resolution analog-to-digital converters(ADC)are quantized and affected by channel noise.Therefore,a one-bit massive MIMO channel estimation method is proposed in this paper.The channel matrix is regarded as a two-dimensional image.In order to enhance the significance of noise features in the image and remove them,the channel attention mechanism is introduced into the conditional generative adversarial network(CGAN)to generate channel images,and im-prove the loss function.The simulation results show that the improved network can use a smaller number of pilots to obtain better channel estimation results.Under the same number of pilots and signal-to-noise ratio(SNR),the channel estimation accuracy can be improved by about 7.5 dB,and can adapt to the scenarios with more antennas.

Electrochemical behavior of Cu in the (NaCl-KCl-CuCl) molten salt

The electrochemical reaction mechanism and electrocrystallization process of Cu on copper electrode in the eutectic NaC1-KC1-CuC1 molten salt were investigated by means of cyclic voltammetry, chronopotentiometry and chronoamperometry tech-nique at 710℃. The results show that the electrochemical reaction process of Cu is a quasi-reversible process mix-controlled by Cu＋ diffusion rate and electron transport rate;the electrochemical reduction mechanism is Cu＋e→Cu;the electrocrystallization process of copper is an instantaneous hemispheroid three-dimensional nucleation process; the Cu diffusino coefficient is 4.3×10^-4cm^2·s^-1 under the experimental conditions.

Crystallographic orientation effect on cutting-based single atomic layer removal

The ever-increasing requirements for the scalable manufacturing of atomic-scale devices emphasize the significance of developing atomic-scale manufacturing technology. The mechanism of a single atomic layer removal in cutting is the key basic theoretical foundation for atomic-scale mechanical cutting. Material anisotropy is among the key decisive factors that could not be neglected in cutting at such a scale. In the present study, the crystallographic orientation effect on the cutting-based single atomic layer removal of monocrystalline copper is investigated by molecular dynamics simulation. When undeformed chip thickness is in the atomic scale, two kinds of single atomic layer removal mechanisms exist in cutting-based single atomic layer removal, namely, dislocation motion and extrusion, due to the differing atomic structures on different crystallographic planes. On close-packed crystallographic plane, the material removal is dominated by the shear stress-driven dislocation motion, whereas on non-close packed crystallographic planes, extrusion-dominated material removal dominates. To obtain an atomic, defect-free processed surface, the cutting needs to be conducted on the close-packed crystallographic planes of monocrystalline copper.

A theoretical model of the femtosecond laser ablation of semiconductors considering inverse bremsstrahlung absorption

The mechanism of the femtosecond laser ablation of semiconductors is investigated. The collision pro cess of free electrons in a conduction band is depicted by the test particle method, and a theoretical model of nonequilibrium electron transport on the femtosecond timescale is proposed based on the FokkerPlanck equa tion. This model considers the impact of inverse bremsstrahlung on the laser absorption coefficient, and gives the expressions of electron drift and diffusion coefficients in the presence of screened Coulomb potential. Numerical simulations are conducted to obtain the nonequilibrium distribution function of the electrons. The femtosecond laser ablation thresholds are then calculated accordingly, and the results are in good agreement with the experimental results. This is followed by a discussion on the impact of laser parameters on the ablation of semiconductors.

Studies on Hydrolysis Mechanism of Anticancer Ruthenium Drug ImH[trans-Ru（Im）2Cl4] via ABEEMσπ Polarizable Force Field Combined with QM and MD-FEP

We used ABEEMon（atom-bond electronegativity equalization method） polarizable force field（ABEEMσπ PFF） method combined with QM and molecular dynamics-free energy perturbation（MD-FEP） methods to investigatethe function of water molecules in hydrolysis process of ImH[trans-Ru（Im）2Cl4]（ICR）. The activation free energiesobtained via MD-FEP calculation are in fair agreement with the experimental data. In addition, QM/MM（ABEEM）rationally describes the charge distributions and the electrostatic interaction between molecules. ABEEMσπ fluctua-ting charge model has the following good characteristics： （1） not only atomic charge regions but also σ,π bond andlone pair charge regions are explicitly represented for a molecule; （2） the region charges are geometry dependent andcalculated from time to time in the dynamic simulation without any iterative procedure so that its performance istime-saving compared with the Drude model and induced dipole model.