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Manganese porphyrin-mediated aerobic epoxidation of propylene with isoprene: A new strategy for simultaneously preparing propylene epoxide and isoprene monoxide

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Chinese Chemical Letters 2023年第3期34卷 236-239页

作者： Xian-Tai Zhou hai-yang yu yang Li hai-Bo Wu Hong-Bing Ji Fine Chemical Industry Research Institute School of Chemical Engineering and TechnologySun Yat-sen UniversityZhuhai 519082China Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Huizhou Research Institute Sun Yat-sen UniversityHuizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516003China

The direct epoxidation of propylene by O_(2) is a significant and challenging topic. The key factor for this homogeneous aerobic epoxidation is the activation of molecular oxygen under mild conditions. In this work,the aerobic epoxidation of propylene catalyzed by manganese porphyrins was achieved in the presence of isoprene. Isoprene contains an allyl methyl group, and the α-H can be easily removed to achieve the activation of molecular oxygen. The conversion of propylene was 38% and the selectivity toward propylene oxide(PO) was up to 87%. The role of isoprene was demonstrated, and a plausible mechanism was proposed. The protocol reported herein is expected to provide a strategy for the simultaneous preparation of propylene oxide and isoprene monoxide.

关键词： Propylene Epoxidation Dioxygen Isoprene Metalloporphyrins

Controllable synthesis of nanorod/nanodisk TiO_2 from titanium-containing electric furnace molten slag

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Rare Metals 2015年第4期34卷 267-275页

作者： Zai-Qing Que yang Li hai-yang yu Feng Zheng Mei Zhang Min Guo State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Nanostructured TiO2 with different morphologies and crystal phases was successfully synthesized from titanium-containing electric furnace molten slag by using a hydrothermal method followed by reflux process in acid solution. The effects of acid concentration, reflux time, and acid type on the formation of TiO2 were systematically investigated by scanning electron microscopy, X-ray dif- fraction （XRD）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM）, and X-ray fluorescence （XRF）. It is indicated that TiO2 nanorod with rutile phase is achieved in nitric or hydrochloric acid, while anatase TiO2 nanodisk is formed in sulfuric acid. With the increase of the concentration of hydrochloric acid from 0.3 to 1.5 mol-L-1, the dispersibility and crystallinity of the final product can be improved. With prolonging the reflux time from 6 to 14 h, the rutile TiO2 nanorod with uniform crystal size and high crystallinity is obtained. The growth mechanism of TiO2 nanorod and nanodisk prepared under different conditions was also discussed.

关键词： Titanium-containing electric furnace molten slag TiO2 Nanorod Nanodisk Hydrothermal method

Risk of asthma in preterm infants with bronchopulmonary dysplasia: a systematic review and meta‑analysis

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World Journal of Pediatrics 2023年第6期19卷 549-556页

作者： Tong Sun hai-yang yu Miao yang Yi-Fan Song Jian-Hua Fu Department of Pediatrics Shengjing Hospital of China Medical UniversitySanhao StreetHeping DistrictShenyangChina Department of Neurology Shengjing Hospital of China Medical UniversityShenyangChina

Background This study aimed to systematically review and meta-analyze the available literature on the association between preterm infant bronchopulmonary dysplasia(BPD)and pre-adulthood *** Studies examining the association between BPD and asthma in children and adolescents were systematically reviewed,and a meta-analysis was *** searched Scopus,Embase,Web of Science,PubMed,and Cochrane Library from the database inception to March 26,*** pooled odds ratio(OR)estimate was used in our meta-analysis to calculate the correlation between BPD and the probability of developing asthma before *** 12.0 was used to conduct the statistical *** The correlation between asthma and BPD in preterm newborns was examined in nine *** used a random effect model to pool the OR *** results indicated a marked increase in the risk of subsequent asthma in preterm infants with BPD[OR=1.73,95% confidence interval(CI)=1.43-2.09].Moreover,there was no obvious heterogeneity across the studies(P=0.617,I^(2)=0%).The pooled OR remained stable and ranged from 1.65(95%CI=1.35-2.01)to 1.78(95%CI=1.43-2.21).Regarding publication bias,the funnel plot for asthma risk did not reveal any noticeable *** further performed Begg’s and Egger’s tests to quantitatively evaluate publication *** was no evidence of a publication bias for asthma risk(P>|Z|=0.602 for Begg’s test,and P>|t|=0.991 for Egger’s test).Conclusions Our findings indicate that preterm infants with BPD have a much higher risk of developing asthma in the future(OR=1.73,95%CI=1.43-2.09).Preterm infants with BPD may benefit from long-term follow-up.

关键词： Asthma Bronchopulmonary dysplasia Preterm infants

Cisplatin-loaded Poly(L-glutamic acid)-g-Methoxy Poly(ethylene glycol) Nanoparticles as a Potential Chemotherapeutic Agent against Osteosarcoma

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Chinese Journal of Polymer Science 2015年第5期33卷 763-771页

作者： Yi-fei Li hai-yang yu hai Sun 刘建国汤朝晖 Dan Wang Lian-you yu Xue-si Chen Departemnt of Orthopaedics the Norman Bethune First Hospital of Jilin University Jilin Central Hospital Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences Basic Medical College Beihua University The Hospital of Jilin Chemical Industry Company

Herein, cisplatin-loaded poly（L-glutamic acid）-g-methoxy poly（ethylene glycol） nanoparticles were evaluated as a potential chemotherapeutic agent against osteosarcoma by using alone or with an i RGD（internalizing RGD, CRGDKDPDC）. The release rate of platinum from the cisplatin-loaded nanoparticles CDDP/PLG160-g-m PEG2K（CDDP-NPs） accelerated with the increase of the acidity of the environment. In vitro test demonstrated that CDDP-NPs could inhibit the proliferation of MNNG/Hos osteosarcoma cells with IC50（72 h） of 12.2 μg·mL^-1. In vivo test for MNNG/Hos osteosarcoma tumor bearing mice exhibited that CDDP-NPs had comparable or slightly higher efficacy but significantly lower side effects in comparison with free CDDP. The coadministration of i RGD could further enhance the anticancer efficacy of CDDP-NPs against MNNG/Hos osteosarcoma without bringing obvious side effects. Therefore, CDDP-NPs using alone or with iRGD have great potential for the treatment of osteosarcoma.

关键词： Nanoparticles Biodegradable polymers Cancer chemotherapy Polymeric drug carrier

Propylene epoxidation coupled with furfural oxidation over Pt(Ⅱ) TPP porphyrin with molecular oxygen

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Green Chemical Engineering 2024年第4期5卷 519-525页

作者： Hong-Qi Li hai-yang yu yang Li Xiao-Qi He Xian-Tai Zhou Huizhou Research Institute Sun Yat-sen UniversityHuizhou516081China School of Chemical Engineering and Technology Sun Yat-sen UniversityZhuhai519082China

The development of green route for preparing propylene oxide(PO)with molecular oxygen is of significance both in academic and *** this work,propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin(Pt(Ⅱ)TPP)has been *** conversion and PO selectivity reached up to 56%and 83%,***,furfural was almost completely converted to furoic *** on operando characterizations and electron paramagnetic resonance(EPR)tests,a mechanism involved high-valent Pt species was *** work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry.

关键词： Propylene Epoxidation Molecular oxygen Furfural Platinum porphyrins

Graphite-polypyrrole coated 316L stainless steel as bipolar plates for proton exchange membrane fuel cells

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 53-58页

作者： Li-jun yang hai-jun yu Li-jun Jiang Lei Zhu Xu-yu Jian Zhong Wang Energy Materials and Technology Research Institute Beijing General Research Institute for Nonferrous Metals Beijing 100088 China

316L stainless steel（SS 316L） is quite attractive as bipolar plates in proton exchange membrane fuel cells（PEMFC）.In this study,graphite-polypyrrole was coated on SS 316L by the method of cyclic *** surface morphology and chemical composition of the graphite-polypyrrole composite coating were investigated by scanning electron microscopy（SEM） and X-ray photoelectron spectroscopy（XPS）.A simulated working environment of PEMFC was applied for testing the corrosion properties of graphite-polypyrrole coated SS *** current densities in the simulated PEMFC anode and cathode conditions are around 3×10-9 and 9×10-5 A·cm-2,*** addition,the interfacial contact resistance（ICR） was also *** ICR value of graphite-polypyrrole coated SS 316L is much lower than that of bare SS ***,graphite-polypyrrole coated SS 316L indicates a great potential for the application in PEMFC.

关键词： proton exchange membrane fuel cells polypyrrole graphite corrosion contact resistance stainless steel

A compositional model for CO_(2) ooding including CO_(2) equilibria between water and oil using the Peng–Robinson equation of state with the Wong–Sandler mixing rule

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Petroleum Science 2019年第4期16卷 874-889页

作者： Zhong-Lin yang hai-yang yu Zhe-Wei Chen Shi-Qing Cheng Jian-Zheng State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China State Energy Center for Shale Oil Research and Development Beijing 100083China School of Petroleum Engineering China University of PetroleumBeijing 102249China

This paper presents a three-dimensional, three-phase compositional model considering CO2 phase equilibrium between water and oil. In this model, CO2 is mutually soluble in aqueous and hydrocarbon phases, while other components, except water,exist in hydrocarbon phase. The Peng–Robinson(PR) equation of state and the Wong–Sandler mixing rule with non-random two-liquid parameters are used to calculate CO2 fugacity in the aqueous phase. One-dimensional and three-dimensional CO2 flooding examples show that a significant amount of injected CO2 is dissolved in water. Our simulation shows 7% of injected CO2 can be dissolved in the aqueous phase, which delays oil recovery by 4%. The gas rate predicted by the model is smaller than the conventional model as long as water is undersaturated by CO2, which can be considered as 'lost' in the aqueous phase. The model also predicts that the delayed oil can be recovered after the gas breakthrough, indicating that delayed oil is hard to recover in field applications. A three-dimensional example reveals that a highly stratified reservoir causes uneven displacement and serious CO2 breakthrough. If mobility control measures like water alternating gas are undertaken, the solubility e ects will be more pronounced than this example.

关键词： CO_(2)flooding Wong-Sandler mixing rule Equation of state Numerical simulation CO2 solubility

Separation and comprehensive utilization of valuable elements in Ti-bearing electric arc furnace molten slag

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Journal of Iron and Steel Research International 2018年第5期25卷 487-496页

作者： yang Li hai-yang yu Hua-mei yang Feng Zheng Xiong Zhang Bei-bei Xiong Qiang Zhen Hong-wei Ni The State Key Laboratory of Refractories and Metallurgy School of Materials and Metallurgy Wuhan University ofScience and Technology Wuhan 430081 Hubei China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083 China Nano-science and Nano-technology Research Center Materials Science and Engineering College ShanghaiUniversity Shanghai 200444 China

A novel route to comprehensive utilization of valuable elements such as Ti, A1, Si and Mg in Ti-bearing electric arc furnace molten slag （Ti-bearing EAF slag） was proposed. The route can be expressed as a three-step process including alkali fusion, water leaching and acidolysis. Following these processes under the optimum conditions, the recovery ratios of TiO2, Al2O3, SiO2 and MgO were about 97.5, 93.5, 27.9 and 53.5%, respectively. Meanwhile, nanostructured TiO2, NaA zeolite and Mg（OH）2 fire retardant were synthesized simultaneously by using Ti-bearing EAF slag as raw materials. In addition, the photocatalytic activity of prepared nanostructured TiO2 and the adsorption property of obtained NaA zeolite were investigated. The results showed that the photodegradation efficiency of as-prepared TiO2 was 80% for rhodamine B and the adsorption efficiency of NaA zeolite was 61% for Cu2＋ under the optimum conditions.

关键词： Ti-bearing electric arc furnace molten slag - Comprehensive utilization Valuable element TiO2 photocatalyst ·NaA zeolite Mg(OH)2 fire retardant

Microstructural evolution and abrasive resistance of WC7Co ceramic particle-reinforced Ti6Al4V composite coating prepared by pulse laser cladding

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Journal of Iron and Steel Research International 2020年第2期27卷 228-237页

作者： Li-jing yang Shao-peng Wang Pei Wang Huan Li hai-yu yang yuan-sheng Ye Zheng-xian Li Northwest Institute for Non-ferrous Metal Research.Xi'an 710016 ShaanxiChina

WC7Co/Ti6Al4V composite coatings are deposited on the pure Ti substrate by pulse laser cladding(LC).During the laser melting process,the decomposition of WC7Co particles will lead to the evolution of microstructure and phases,which is directly related to the wear resistance and mechanism of composite *** microstructural evolution,phase compositions and interface reaction of WC7Co/Ti6Al4V composite coating were examined by scanning electron microscopy,energydispersive spectrum and X-ray diffraction(XRD).The hardness of different structures and abrasive resistance of composite coating were *** results show that the typical microstructure of LC WC7Co/Ti6Al4V composite coating can be classified into dissolved WC7Co composite structure and un-dissolved WC7Co *** to XRD results,there are Ti solid solution,W,TiC,VC,Co3W3C and secondary W2C in composite *** eutectic structure formed by the dissolved WC7Co particles consisted of W,W2C,TiC and P-Ti solid *** mean hardness of different structures exhibits a significant gradient distribution in composite coating.A reaction layer composed of TiC,W and W2C is also generated onto the interface between un-dissolved WC7Co particles and Ti6Al4V alloy *** abrasive mechanisms of WC7Co/Ti6Al4V composite coating are mainly adhesive wear and oxidation wear during the dry sliding process.

关键词： Laser cladding WC ceramic powder Titanium alloy Wear resistance Composite coating