Microstructure evolution and thermal expansion of Cu-Zn alloy after high pressure heat treatment

The thermal expansion coefficients of Cu-Zn alloy before and after high pressure treatment were measured by thermal expansion instrument in the temperature range of 25？700 ℃,and the microstructure and phase transformation of the alloy were examined by optical microscope,X-ray diffractometer（XRD） and differential scanning calorimeter（DSC）.Based on the experimental results,the effects of high pressure treatment on the microstructure and thermal expansion of Cu-Zn alloy were investigated.The results show that the high pressure treatment can refine the grain and increase the thermal expansion coefficient of the Cu-Zn alloy,resulting in that the thermal expansion coefficient exhibits a high peak value on the α-T curve,and the peak value decreases with increasing the pressure.

Microstructure evolution and thermal physical properties of CuCr alloy after high pressure treatment

The thermal diffusion coefficient, thermal conductivity, and thermal expansion coefficient of CuCr alloy prepared by infiltration were measured by thermal constant tester and dilatometer before and after high pressure heat treatment, at the same time, the effect of high pressure treatment on the thermal physical properties of CuCr alloy was discussed by the analysis of its microstructure. The experimental results show that high pressure heat treatment can increase the thermal diffusion coefficient and thermal conductivity of CuCr alloy, but it changes slightly in the pressure range of 1-6 GPa. As for thermal expansion coefficient, when the temperature is higher than 130 °C, it is obviously higher than that of the alloy without high pressure treatment after 1 GPa pressure treatment, and the higher the temperature is, the larger their differences are.

Train of Thought about Treatment of High Blood Pressure with Integrative Traditional and Western Medicine

Based on the differ—ent theories,TCM andWestern medicine(WM)have their owndifferent understandingsabout the pathogenesisand treatment of highblood pressure(HBP).In TCM the balancesbetween blood-qi,vis—cera—bowel, and yin—yang are all highly

Synergistic Effect of Atmospheric Pressure Plasma Pre-Treatment on Alkaline Etching of Polyethylene Terephthalate Fabrics and Films

Dyeing of PET materials by traditional methods presents several problems.Plasma technology has received enormous attention as a solution for the environmental problems related with textile surface modifications,and there has been a rapid development and commercialization of plasma technology over the past decade.In this work,the synergistic effect of atmospheric pressure plasma on alkaline etching and deep coloring of dyeing properties on polyethylene terephthalate（PET）fabrics and films was investigated.The topographical changes of the PET surface were investigated by atomic force microscopy（AFM）images,which revealed a smooth surface morphology of the untreated sample whereas a high surface roughness for the plasma and/or alkaline treated samples.The effects of atmospheric pressure plasma on alkaline etching of the structure and properties of PET were investigated by means of differential scanning calorimetry（DSC）,the main objective of performing DSC was to investigate the effect of the plasma pre-treatment on the T_g and T_m.Using a tensile strength tester YG065 H and following a standard procedure the maximum force and elongation at maximum force of PET materials was investigated.Oxygen and argon plasma pre-treatment was found to increase the PET fabric weight loss rate.The color strength of PET fabrics was increased by various plasma pre-treatment times.The penetration of plasma and alkaline reactive species deep into the PET structure results in better dyeability and leaves a significant effect on the K/S values of the plasma pre-treated PET.It indicated that plasma pre-treatment has a great synergistic effect with the alkaline treatment of PET.

Surface Modification of Polyimide Film by Dielectric Barrier Discharge at Atmospheric Pressure

In this paper,polyimide（PI）films are modified using an atmospheric pressure plasma generated by a dielectric barrier discharge（DBD）in argon.Surface performance of PI film and its dependence on exposure time from 0 s to 300 s are investigated by dynamic water contact angle（WCA）,field emission scanning electron microscopy（FESEM）,and Fourier transform infrared spectroscopy in attenuated total multiple reflection mode（FTIR-ATR）.The study demonstrates that dynamic WCA exhibits a minimum with 40 s plasma treatment,and evenly distributed nano-dots and shadow concaves appeared for 40 s and 12 s Ar plasma treatment individually.A short period of plasma modification can contribute to the scission of the imide ring and the introduction of C-O and C=O（-COOH）by detailed analysis of FTIR-ATR.

Influence of Chemical Precleaning on the Plasma Treatment Efficiency of Aluminum by RF Plasma Pencil

This paper is aimed to show the influence of initial chemical pretreatment prior to subsequent plasma activation of aluminum surfaces.The results of our study showed that the state of the topmost surface layer（i.e.the surface morphology and chemical groups）of plasma modified aluminum significantly depends on the chemical precleaning.Commonly used chemicals（isopropanol,trichlorethane,solution of Na OH in deionized water）were used as precleaning agents.The plasma treatments were done using a radio frequency driven atmospheric pressure plasma pencil developed at Masaryk University,which operates in Ar,Ar/O_2 gas mixtures.The effectiveness of the plasma treatment was estimated by the wettability measurements,showing high wettability improvement already after 0.3 s treatment.The effects of surface cleaning（hydrocarbon removal）,surface oxidation and activation（generation of OH groups）were estimated using infrared spectroscopy.The changes in the surface morphology were measured using scanning electron microscopy.Optical emission spectroscopy measurements in the near-to-surface region with temperature calculations showed that plasma itself depends on the sample precleaning procedure.

Prospects for High-quality Development of Water Resources

The water resources of rivers and reservoirs with a five-meter drop are used to discuss the technical theory and the cost and practical value of equipment cases.The high-quality development technology of water resources explored in this paper provides a feasible plan for achieving the goal of innovation to zero.

Pore structure of selected Chinese coals with heating and pressurization treatments

Pore structure of Chinese coals with heating and pressurization treatments was studied using small angle X-ray scattering （SAXS）, N2 adsorption/desorption isotherms and scanning electron microscope （SEM）. SAXS was performed for some sam- ples after heat treatment at seven elevated temperatures from 25 to 250℃ at 0 MPa and for other samples with hydrostatic pressure treatment at 0, 5, 10, 15 and 20 MPa at the room temperature. The results show that N2 adsorption isotherm together with SAXS could be a comprehensive method to evaluate the pore shape and the pore size distribution： the pore shapes are generally spherical for low rank coal and they are mainly ellipsoidal for high rank coal. All these measurements were then interpreted using the fractal theory to reveal relationship between surface fractals and coal rank, and the evolution of surface fractals under heating and pressurization treatments. The results show that surface fractal dimension （Ds） changes with different treating temperature and pressure and maximum vitrinite reflectance （Ro,m）. Especially in the bituminous stage, Ds shows an increasing trend with Ro,m under varied temperatures. Moreover, Ds shows an increasing trend with increasing temperature before 200℃, and a decreasing trend after 200℃. Furthermore, the results show that Ds has a more complex relationship with Ro.m under varied treating temperature than that under varied treating pressure.

高压热处理调节FeP金属玻璃空化行为

脆性金属玻璃的空化现象可追溯其本征的高原子密度涨落.有目的地调节金属玻璃内部结构以抑制其空化行为一直是被关注的问题.本文通过分子动力学模拟研究了高压热处理对脆性Fe_(80)P_(20)金属玻璃空化行为的影响.高压热处理可诱导Fe_(80)P_(20)金属玻璃发生年轻化,有效抑制空化的发生.伴随压力和温度的增加,Fe_(80)P_(20)金属玻璃的空间异质性逐渐减小,同时磷原子的分布变得相对均匀.分析表明,高压热处理可诱导Fe_(80)P_(20)金属玻璃局部原子结构从“类液态”转变为“类固态”,致使空化需要更大的外加应力诱发.上述结果为理解金属玻璃的空间异质性和空化行为之间的关联规律提供了新的思路.