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Effect of phosphate-based sealing treatment on the corrosion performance of a PEO coated AZ91D mg alloy

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Journal of Magnesium and Alloys 2020年第4期8卷 1328-1340页

作者： Kun Qian weizhou Li Xiaopeng Lu Xinxin Han Yong Jin Tao Zhang Fuhui Wang School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Processing Non-ferrous Metals and Features Materials Guangxi UniversityNanning 530004China Shenyang National Laboratory for Materials Science Northeastern University3-11 Wenhua RoadShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

This study investigated the effect of sealing treatment on the corrosion performance of plasma electrolytic oxidation(PEO)coated AZ91D Mg alloy with and without addition of corrosion *** microstructure,phase composition and corrosion property of the sealed and unsealed coatings were evaluated by using scanning electron microscopy(SEM),energy dispersion spectroscopy(EDS),x-ray diffraction(XRD),x-ray photoelectron spectroscopy(XPS),polarization,and electrochemical impedance spectroscopy(EIS)*** experiments and salt spray tests showed that,after sealing in phosphate solution containing corrosion inhibitor,the corrosion current density of PEO-coated AZ91D decreased more than 10-fold and the anti-corrosion time in a salt spray environment increased more than *** corrosion rate of the PEO coating slowed down due to the releasing and adsorbing of the corrosion inhibitors in the pores and cracks of the coating during the corrosion process.

关键词： AZ91D magnesium alloy:Plasma electrolyte oxidation Sealing treatment Corrosion inhibitor

Optical Transitions in Cr Doped Bi_(4)Ge_(3)O_(12) Crystal

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Chinese Physics Letters 1994年第6期11卷 383-386页

作者： HUANG Yingpeng FENG Xiqi HU Guanqin YANG Baocheng LING Yuanqi PANG weizhou ZHU Jikang Shanghai Institute of Ceramics Academia SinicaShanghai 200050 Department of Physics East China Normal UniversityShanghai 200062

In this paper,we present the results of the optical absorption spectra of Cr doped Bi_(4)Ge_(3)O_(12) crystal at room temperature and compare them with the theoretical results of a multifold scattering(MS)-Xαcalculation which include the energy-level structures and the transition energies of Cr^(3+)and Cr^(4+)located in Ge-site in the crystal.

关键词： crystal MS Transition

Growth and F_v/F_m in embryos of Hizikia fusiformis (Harvey) Okamura (Sargassaceae,Phaeophyta) cultured under different temperature and irradiance conditions

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Journal of Oceanology and Limnology 2018年第5期36卷 1798-1805页

作者： WANG Longle ZHANG Xin ZOU Dinghui CHEN weizhou JIANG Heng School of Environment and Energy South China University of TechnologyGuangzhou 510006China The Science and Technology Division South China University of TechnologyGuangzhou 510006China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou 510006China Marine Biology Institute Science CenterShantou UniversityShantou 515063China

Understanding the embryo physiology of Hizikia fusiformis（Harvey） Okamura will promote the development of artificial seedlings. In this study, H. fusiformis embryos were cultured under different environmental conditions, including different temperatures（15℃, 20℃, and 25℃）, sunlight intensities（100%, 50%, and 25% of full solar radiation） and types of UVR（UV-A and UV-B）. Then, we determined the lengths, maximal quantum yields（ Fv/Fm）, and survival rates of the embryos. The results showed that the embryos had the highest lengths, Fv/Fm values and survival percentages when cultured under a temperature of 20℃ and 25% sunlight intensity. The full level of solar radiation severely reduced the growth and survival ratios of the embryos. Hizikia embryos recovered within 2 h from the damage caused by short-term（30 min） high radiation（about 70% of full solar radiation） and UVR exposure. However, the viabilities of the embryos were significantly decreased after 4 h exposure to UVR. According to these results, we propose that culture conditions with indoor natural light and room temperature would be favorable for the growth, development and physiology of H izikia embryos.

关键词： Hizikia fusiformis embryos growth Fv/Fm temperature irradiance

人工智能影像诊断系统在老年人肺结核主动筛查中的应用

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医学动物防制 2024年第6期40卷 618-622页

作者：黄宝杨吴世幸周丽芳廖维洲杨俊赖文胜韦概龙柳州市疾病预防控制中心广西壮族自治区柳州545007

目的初步评估人工智能(artificial intelligence,AI)影像诊断系统(简称“AI系统”)在柳州市老年人中开展肺结核主动筛查的应用价值。方法2021年9月—2022年5月柳州市基层医疗卫生机构应用AI系统对老年人进行肺结核主动筛查。分别收集AI... 详细信息

目的初步评估人工智能(artificial intelligence,AI)影像诊断系统(简称“AI系统”)在柳州市老年人中开展肺结核主动筛查的应用价值。方法2021年9月—2022年5月柳州市基层医疗卫生机构应用AI系统对老年人进行肺结核主动筛查。分别收集AI系统与柳州市结核病定点医院影像专家的肺结核诊断结果。采用配对χ^(2)检验考察AI系统和影像专家诊断结果的差异,采用Kappa分析考察诊断结果的一致性。结果共6320名研究对象,男女比例为1∶1.21,年龄65~98岁,中位年龄为70(67,75)岁(D=0.127,P<0.001)。研究对象的AI诊断百分值在0%~99.50%,中位值为0%(0%,1.30%)(D=0.423,P<0.001)。AI系统和影像专家的诊断结果分别为肺结核者占5.44%和4.49%;疑似肺结核者占6.27%和5.70%;非肺结核者占88.29%和89.81%。配对χ^(2)检验结果显示χ^(2)=59.759,P<0.001;AI系统识别(疑似)肺结核者的灵敏度约为95.19%,识别非肺结核者的特异度约为97.76%,约登指数约为0.93;Kappa分析结果显示Kappa=0.861,P<0.001。结论针对柳州市老年人肺结核主动筛查,AI系统的诊断结果与柳州市结核病定点医院影像专家的诊断结果有较高的一致性,AI系统在柳州市老年人肺结核主动筛查中有较高的诊断价值。

关键词：人工智能肺结核老年人筛查

Degradation of Nitrobenzene Wastewater via Iron/Carbon Micro-electrolysis Enhanced by Ultrasound Coupled with Hydrogen Peroxide

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China Petroleum Processing & Petrochemical Technology 2017年第4期19卷 72-81页

作者： Qin Yuejiao Yu Lisheng Luo Shuai Jiao weizhou Liu Youzhi Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of China Department of Civil and Environmental Engineering Virginia Polytechnic Institute and State University

The zero valent iron/granular active carbon(ZVI/GAC) micro-electrolysis enhanced by ultrasound(US) coupled with hydrogen peroxide(H_2O_2) was investigated for the deep degradation of nitrobenzene-containing wastewater. The results of scanning electron microscopy-energy dispersive X-rays analysis(SEM-EDS) demonstrated that continuously accelerated regeneration of ZVI and GAC in situ by US could improve the process for converting nitrobenzene(NB) to aniline(AN). H_2O_2 was decomposed catalytically by the byproduct Fe^(2+) ions generated in the micro-electrolysis process to hydroxyl radicals and the organic pollutants in the wastewater were finally mineralized to CO2 and H2O. Effects of the ZVI dosage, the ZVI/GAC mass ratio, the initial pH value and the H_2O_2 dosage on the efficiency for degradation of NB were studied in these experiments. The optimal operating conditions covered a ZVI dosage of 15 g/L, a ZVI/GAC mass ratio of 1:2,an initial pH value of 3 and a H_2O_2 dosage of 4 mL. In this case, the NB removal efficiency reached 97.72% and the total organic carbon(TOC) removal efficiency reached 73.42% at a NB concentration of 300 mg/L. The reduction of NB by USZVI/GAC followed the pseudo-first-order kinetics model, and the pseudo-first-order rate constants were given at different initial pH values. The reaction intermediates such as AN, benzoquinonimine, p-benzoquinone, p-nitrophenol and other organic acids were detected and a probable pathway for NB degradation has been proposed.

关键词： iron/carbon micro-electrolysis ultrasound hydrogen peroxide nitrobenzene wastewater treatment degradation mechanisms

The Nd-Sr isotope study of Mesozoic granitoids in Jiangxi Province

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Chinese Science Bulletin 1999年第15期44卷 1427-1431页

作者： weizhou Shen Hongfei Ling Wuxian Li Dezi Wang Xuan Huang Jun Pan Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

Nd-Sr isotopic compositions of 12 Mesozoic granitoids from Jiangxi Province have been reported. They show loe-εND（-13.8—- 8.3）, high-lsr（0.71069—0.73981） and old tDM （2087—1635 Ma）. Comparison between the Sm-Nd isotopic compositions of the granitoids and those of the basement metamorphic rocks suggests that these granitoids were mainly derived from the metasedimentary rocks. There is an east-west trend Mesozoic granitoid zone with lowtDM from S. Jiangxi to S. Fujian. The origin of these granites was preliminarily discussed.

关键词： Nd-Sr isotopic compositions material source low-tDM zone Mesozoic granitoids Jiangxi Province.

Degradation of Nitrobenzene-Containing Wastewater with O_3 and H_2O_2 by High Gravity Technology

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China Petroleum Processing & Petrochemical Technology 2013年第1期15卷 85-94页

作者： Jiao weizhou Liu Youzhi Liu Wenli Li Jing Shao Fan Wang Chaoran Research Center of Shanxi Province for High Gravity Chemical Engineering and Technology North University of China

Nitrobenzene-containing industrial wastewater was degraded in the presence of ozone coupled with H2O2 by high gravity technology. The effect of high gravity factor, H2O2 concentration, pH value, liquid flow-rate, and reaction time on the efficiency for removal of nitrobenzene was investigated. The experimental results show that the high gravity technology enhances the ozone utilization efficiency with O3/H202 showing synergistic effect. The degradation efficiency in terms of the COD removal rate and nitrobenzene removal rate reached 45.8% and 50.4%, respectively, under the following reaction conditions, viz.： a high gravity factor of 66.54, a pH value of 9, a H2O2/O3 molar ratio of 1：1, a liquid flow rate of 140 L/h, an ozone concentration of 40 rag/L, a H2O2 multiple dosing mode of 6 mL/h, and a reaction time of 4 h. Compared with the performance of conventional stirred aeration mixers, the high gravity technology could increase the COD and nitrobenzene removal rate related with the nitrobenzene-containing wastewater by 22.9% and 23.3%, respectively.

关键词： nitrobenzene,containing wastewater rotating packed bed ozone H2O2 free radicals

Degradation of Wastewater Containing Nitrobenzene by High Gravity-Ultrasonic/Ozonation/Electrolysis Technology

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China Petroleum Processing & Petrochemical Technology 2012年第3期14卷 96-101页

作者： Jiao weizhou Liu Youzhi Shao Fan Liu Wenli Li Jing Wang Chaoran Research Center of Shanxi Province for High Gravity Chemical Engineering and Technology North University of China

The integrated high gravity-ultrasonic/ozonation/electrolysis technology was applied in the pretreatment of wastewater containing nitrobenzene. The effect ofpH value, high gravity factor, liquid flow-rate and electric current density on removal of COD and nitrobenzene compounds was investigated. Experimental results have determined the optimal pro- cess regime involving a high gravity factor of 100, an electric current density of 20 mA/cm2, a liquid flow-rate of 100 L/h, and an initial liquid pH value of 11. After the wastewater had been treated for 180 rain, the degradation of nitrobenzene and COD reached 99% and 80%, respectively, with the biochemical coefficient （BOD/COD） equating to 0.64, and the subse- quent treatment of wastewater could be carried out by conventional biochemical means. Compared with traditional aeration- ozone contactors, a rotating packed bed with high mass transfer characteristics could be used to increase the ozonation treat- ment efficiency.

关键词： high gravity nitrobenzene ultrasonic electrochemistry ozone

Effects of Coexisting Substances on Nitrobenzene Degradation with O_3/H_2O_2 Process in High-Gravity Fields

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China Petroleum Processing & Petrochemical Technology 2016年第4期18卷 32-40页

作者： Zhang Shiguang Qin Yuejiao Zhang Dongming Jiao weizhou Guo Liang Liu Youzhi shanxi province key laboratory of higee-oriented chemical engineering north university of china Taiyuan 030051

This study used nitrobenzene as the simulated pollutant to study the effects of common inorganic sodium salts and organics on nitrobenzene degradation by O_3/H_2O_2 in high-gravity fields. The experiment results showed that the highgravity technology could increase the nitrobenzene removal rate by improving the ozone transfer efficiency and ozone dissolution. Coexisting substances had different effects on the degradation kinetics of nitrobenzene in high-gravity fields. Among such substances, Na_2CO_3, NaOH, Na_3PO_4, and NaNO_3 accelerated the removal of nitrobenzene. The main action principle of nitrobenzene degradation by O_3/H_2O_2 is that the additives can increase the pH value of the solution, stimulate ozonolysis, generate hydroxyl radicals(·OH), and improve oxidation efficiency. By contrast, NaCl, NaHCO_3, NaHSO_4, ethanol(C_2H_5OH), acetic acid(CH_3COOH), formic acid(HCOOH), and tert-butyl alcohol(TBA) inhibited nitrobenzene removal. When NaHCO_3, CH_3COOH, or HCOOH were added, the pH value of the solution decreased and free radical chain reactions were hindered. However, NaCl, NaHCO_3, C_2H_5OH, and TBA consumed ·OH radicals and inhibited nitrobenzene removal.

关键词： wastewater nitrobenzene coexisting substance high gravity ozone hydrogen peroxide