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FINITE-PART INTEGRAL AND BOUNDARY ELEMENT METHOD FOR INTERACTION BETWEEN TWO PARALLEL PLANAR CRACKS IN THREE-DIMENSIONAL FINITE BODIES

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Acta Mechanica Solida Sinica 1998年第2期11卷 95-103页

作者： wang aiqin Qin Taiyan Xian Highway Univ Dept Basic Sci Xian 710064 Peoples R China China Agr Univ Dept Basic Sci Beijing 100083 Peoples R China

By using the Somigliana representation and the concepts offinite-part integrals, a set of hypersingular integral equations ofthe interaction between two parallel planar cracks in a three-dimen-sional finite body subjected to arbitrary loads is derived, and thenits numerical method is proposed by the finite-part integral methodcombined with the boundary element method. According to the analytictheory of hypersingular integral equations, the square root models ofdisplacement discontinuities in the elements near the crack front areapplied, and thus the computational precision is raised. Based onthis, the stress intensity factors can be directly ***, the stress intensity factors of sever- al typicalinteraction problems are calculated.

关键词： two parallel planar craclks three-dimensional finite body hypersingularintegral

Ammonium sulfide-assisted hydrothermal activation of palygorskite for enhanced adsorption of methyl violet

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Journal of Environmental Sciences 2016年第3期28卷 33-43页

作者： Guangyan Tian Wenbo wang Yuru Kang aiqin wang Center for Eco-material and Green Chemistry Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China University of the Chinese Academy of Sciences Beijing 100049China R&D Center of Xuyi Palygorskite Applied Technology Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesXuyi 211700China

Herein,palygorskite（PAL）was activated via a simple hydrothermal process in the presence of ammonium sulfide,and the effects of activation on the microstructure,physico-chemical feature and adsorption behaviors of PAL were intensively *** hydrothermal process evidently improved the dispersion of PAL crystal bundles,increased surface negative charges and built more active –Si–O-groups served as the new＂adsorption sites＂.The adsorption property of the activated PAL for Methyl Violet（MV）was systematically investigated by optimizing the adsorption variables,including p H,ionic strength,contact time and initial MV *** activated PAL exhibited a superior adsorption capability to the raw PAL for the removal of MV（from 156.05 to 218.11 mg/g）.The kinetics for MV adsorption followed pseudo second-order kinetic models,while the isotherm and thermodynamics results showed that the adsorption pattern well followed the Langmuir *** structure analysis of PAL before and after adsorption demonstrated that electrostatic interaction and chemical association of –X–O-are the prominent driving forces for the adsorption process.

关键词： Palygorskite Hydrothermal Adsorption Methyl violet

Novel eco-friendly spherical porous adsorbent fabricated from Pickering middle internal phase emulsions for removal of Pb(Ⅱ) and Cd(Ⅱ)

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Journal of Environmental Sciences 2022年第2期34卷 320-330页

作者： Hui Yu Yongfeng Zhu Aiping Hui aiqin wang Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-material and Green ChemistryLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Spherical porous materials prepared from the emulsion template used in the water treatment have displayed a vast prospect, as the high surface area, abundant porous structure, convenient operation and excellent adsorption performance. But the tedious fabrication process, high consumption of organic solvent and surfactant limited the application widely. Herein, a facile and eco-friendly spherical porous adsorbent(SPA) is fabricated from the green surfactant-free(corn oil)-in-water Pickering medium internal phase emulsions(Pickering MIPEs) via the convenient ion crosslinking procedure. The Pickering MIPEs synergistically stabilized with the semi-coke(SC), which is the natural particle produced from the shale oil distillation, and sodium alginate(SA) has excellent storage and anti-coalescence stability. The as-prepared porous adsorbent possessed the abundant pore structure, which provided favorable conditions for effective mass transfer in adsorption, and could be tuned by varying the SA dosage. The saturation adsorption capacities of Pb(II) and Cd(II) can be achieved with 460.54 and 278.77 mg/g within 45 min at 25 ℃, respectively. Overall, this study supplied a viable and eco-friendly route for fabricating the spherical porous adsorbent with a tunable porous structure for heavy metal ion wastewater.

关键词： Spherical porous adsorbent(SPA) Emulsion template Semi-coke Adsorption Heavy metal ion

面向社会人员招生的高职院校母婴护理专业课程体系的构建研究

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创新创业理论研究与实践 2024年第15期7卷 73-77页

作者：李小丹汪爱琴江西卫生职业学院南昌医学院

在社会招生背景下，该文构建出适合高职院校母婴护理专业的课程体系，通过岗位分析，结合文献研究法和半结构式访谈法，构建了高职母婴护理专业课程体系框架，运用德尔菲法进行了2轮专家函询，2轮的问卷应答率和有效率均为100%，构建了... 详细信息

在社会招生背景下，该文构建出适合高职院校母婴护理专业的课程体系，通过岗位分析，结合文献研究法和半结构式访谈法，构建了高职母婴护理专业课程体系框架，运用德尔菲法进行了2轮专家函询，2轮的问卷应答率和有效率均为100%，构建了具有4项一级指标、6项二级指标、30项三级指标的面向社会人员招生的高职院校母婴护理专业课程体系。该课程体系构建科学、可靠，可为社会招生背景下高职院校母婴护理专业人才培养和母婴护理专业群建设进行全面、纵向、深入的教学改革奠定基础。

关键词：社会招生高职母婴护理专业课程体系改革人才培养

Dehydration of xylose to furfural over niobium phosphate catalyst in biphasic solvent system

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Journal of Energy Chemistry 2013年第6期22卷 826-832页

作者： Boonrat Pholjaroen Ning Li Zhiqiang wang aiqin wang Tao Zhang State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Engineering Sichuan University

Phosphoric acid treated niobic acid(NbP)was used for the dehydration of xylose to furfural in biphasic solvent system,which was found to exhibit the best performance among the tested *** excellent performance of NbP could be explained by the better synergistic cooperation between Bro¨nsted and Lewis acid ***,NbP showed good stability and no obvious deactivation or leaching of Nb could be observed after six continuous recycles.

关键词： xylose furfural dehydration biphasic solvent system solid acid catalyst niobium phosphate

Effect of Mineral Admixtures on Alkali-Silica Reaction

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Journal of Wuhan University of Technology(Materials Science) 2008年第1期23卷 16-19页

作者：张承志 wang aiqin Institute of Material and Structure Research Henan University Kaifeng 475004 China Department of Civil Engineering and Architecture Zhongyuan University of Technology Zhengzhou 450007 China

The influence of silica fume, slag and fly ash on alkali-silica reaction under the condition of 70 ℃ is studied. The results show that silica, slag and fly ash may inhibit alkali-silica reaction only under suitable content. When the content is less than 10%, silica fume does not markedly influence the expansion of alkali- silica reaction. When the content is 15%-20%, silica fume only may delay the expansion of alkali-silica reaction. When the content is 30%-70%, slag may only delay the expansion of alkali-silica reaction, but cannot inhibit the expansion of alkali-silica reaction. When the content is 10%, fly ash does not markedly influence the expansion of alkali-silica reaction. When the content is 20%-30%, fly ash may only delay the expansion of alkali-silica reaction, but cannot inhibit the expansion of alkali-silica reaction. When the content is over 50%, it is possible that fly ash can inhibit effectively alkali-silica reaction.

关键词： mineral admixture alkali-silica reaction effectiveness

Amine formylation with CO2 and H2 catalyzed by heterogeneous Pd/PAL catalyst

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Chinese Journal of Catalysis 2019年第8期40卷 1141-1146页

作者： Xingchao Dai Bin wang aiqin wang Feng Shi State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 Gansu China Key Laboratory for Utility of Environment-Friendly Composite Materials and Biomass in University of Gansu Province College of Chemical Engineering Northwest Minzu University Lanzhou 730030 Gansu China Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-materials and Green Chemistry Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 Gansu China University of Chinese Academy of Sciences Beijing 100049 China

For the first time, Pd supported on natural palygorskite was developed for amine formylation with CO2 and H2. Both secondary and primary amines with diverse structures could be converted into the desired formamides at... 详细信息

关键词： Formylation Carbon dioxide Amine Heterogeneous palladium catalyst Formamide

From waste hot-pot oil as carbon precursor to development of recyclable attapulgite/carbon composites for wastewater treatment

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Journal of Environmental Sciences 2019年第1期31卷 346-358页

作者： Jie Tang Bin Mu Li Zong aiqin wang Key Laboratory of Clay Mineral Applied Research of Gansu Province Center of Eco-material and Green Chemistry Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Center of Xuyi Palygorskite Applied Technology Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

The utilization of waste products as valuable materials was a technical imperative for waste management. In this study, the cost-effective attapulgite/carbon(APT/C) composite was developed for wastewater treatment using waste hot-pot oil as a carbon precursor through a facile one-step calcination process. The APT/C composite prepared at 300°C exhibited the excellent adsorption capacity and rapid equilibrium rate over a broad p H range for the removal of various pollutants. More importantly, the removal ratios of the composites toward Methyl Violet and tetracycline still remained 77.6% and 60.2% of the initial adsorption capacity after ten adsorption–regeneration cycles via a facile thermal regeneration strategy, *** all doubt, this research provided a feasible and economical way for the sustainable utilization of waste hot-pot oil in wastewater treatment, achieving the concept of disposal waste with waste and recycling.

关键词： Waste hot-pot oil Calcination Attapulgite/carbon composites Adsorption Thermal regeneration

SnCl_(2)促进的Pt1/PS-PPh_(2)催化剂高选择性催化高碳烯烃氢甲酰化反应

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Chinese Journal of Catalysis 2024年第5期60卷 316-326页

作者：虞周楠张磊磊谈源龙井日峥曹宏晨楼才溢格日乐王军虎王爱琴张涛中国科学院大连化学物理研究所中国科学院应用催化科学技术重点实验室辽宁大连116023 中国科学院大学北京100049 中国科学院大连化学物理研究所低碳催化技术国家工程研究中心辽宁大连116023 中国科学院大连化学物理研究所穆斯堡尔谱数据中心辽宁大连116023

氢甲酰化作为工业上制备醛、醇等含氧化合物的重要反应,广泛应用于制备洗涤剂、增塑剂、表面活性剂和香料等.目前,氢甲酰化反应主要使用HCo(CO)_(4),HCo(CO)_(3)(PR_(3))和HRh(CO)(PPh_(3))_(2)等配合物作为催化剂.尽管Co基催化剂可以... 详细信息

氢甲酰化作为工业上制备醛、醇等含氧化合物的重要反应,广泛应用于制备洗涤剂、增塑剂、表面活性剂和香料等.目前,氢甲酰化反应主要使用HCo(CO)_(4),HCo(CO)_(3)(PR_(3))和HRh(CO)(PPh_(3))_(2)等配合物作为催化剂.尽管Co基催化剂可以将高碳烯烃、内烯烃以及支链烯烃高选择性地转化为直链醛,但其反应条件(5-30 MPa,140-200℃)较苛刻,且容易发生烯烃加氢等副反应.相比之下,Rh催化剂的活性比Co基催化剂高1-2个数量级,且反应条件较为温和.但Rh储量稀少,价格昂贵,而且对于高碳烯烃氢甲酰化反应,Rh催化剂难以分离和循环使用.因此,研究者开展了其他金属催化剂的研究,其中Pt-Sn催化剂因其出色的区域选择性而备受关注.但目前Pt-Sn催化剂多局限于均相催化体系,而且Sn助剂的作用尚不明确.本文采用商业化三苯基膦嫁接的聚苯乙烯小球为载体,通过浸渍法制备了SnCl_(2)-Pt_(1)/PS-PPh_(2)单原子催化剂,考察了其在长链-烯烃氢甲酰化反应中的催化性能,并研究了Sn的促进作用.首先,以1-己烯氢甲酰化为探针反应,对催化剂的组成以及反应条件进行了优化.当Pt/P/Sn=1/2/5时,催化剂表现出最高的催化活性,在90-120℃和4-6 MPa合成气条件下,催化剂转化频率(TOF)为40 h^(-1),产物醛的正异比>42.随后,考察了催化剂的底物适用性.结果表明,C6-C12的高碳烯烃均可被高选择性地转化为相应的醛(正异比>20).然而,在循环使用实验中,由于SnCl_(2)不能稳定锚定在载体上,第二次循环时催化活性降低.但通过补加SnCl_(2),催化活性可以完全恢复.高压热过滤实验及元素检测结果表明,反应过程中Pt没有流失.X射线吸收光谱(XAFS)表征结果表明,反应后Pt仍以单原子形式存在,说明Pt1/PS-PPh_(2)具有良好的稳定性.通过准原位X-射线吸收谱、Mössbauer谱和红外光谱表征对反应过程中Pt和Sn的电子性质和配位结构进行了研究.结果表明,SnCl_(2)在反应过程中逐渐转化为Sn(dioxane)Cl3-物种(1,4-二氧六环为反应溶剂),并与Pt原子形成Pt-Sn键.当反应体系中没有Sn时,Pt(II)会被合成气过度还原并发生团聚.当没有膦配体时,Pt原子也会发生聚集,而且SnCl_(2)会在Pt(II)的催化作用下发生水解生成SnO.因此Sn(dioxane)Cl3-与膦配体共同抑制了Pt(I)在反应过程中的还原与聚集.最后,通过XAFS表征深入研究了反应机理.分析结果表明,CO在催化剂上具有较强的吸附作用,而H_(2)则可能以异裂的方式在催化剂上被活化.据此提出可能的反应机理:首先,H_(2)在催化剂上活化先形成Pt-H物种;随后,烯烃插入Pt-H,形成Pt-烷基物种;接着,CO迁移并插入,生成Pt-酰基物种;最后,经过还原消除步骤,得到最终的产物醛.综上,本文制备了一种对高碳烯烃氢甲酰化反应具有良好催化性能的SnCl_(2)-Pt1/PS-PPh_(2)单原子催化剂,为低成本非Rh基催化剂的开发提供借鉴.同时,揭示了催化体系中Sn的促进作用,为通过Lewis酸来调控催化剂的性能提供了参考.

关键词：氢甲酰化反应铂-锡催化剂高碳烯烃区域选择性单原子催化剂