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Adsorption performance and physicochemical mechanism of MnO

Xiaoyan Deng, Luxing Wang, Qihui Xiu, Ying Wang, Hong Han, Dongmei Dai, Yongji Xu, Hongtao Gao, Xien Liu

《化学科学与工程前沿（英文）》 2021年 第15卷 第3期   页码 538-551 doi: 10.1007/s11705-020-1958-1

摘要： In this work, an adsorbent, which we call MnPT, was prepared by combining MnO , polyethylenimine and tannic acid, and exhibited efficient performance for Cu(II) and Cr(VI) removal from aqueous solution. The oxygen/nitrogen-containing functional groups on the surface of MnPT might increase the enrichment of metal ions by complexation. The maximum adsorption capacities of MnPT for Cu(II) and Cr(VI) were 121.5 and 790.2 mg·g , respectively. The surface complexation formation model was used to elucidate the physicochemical interplay in the process of Cu(II) and Cr(VI) co-adsorption on MnPT. Electrostatic force, solvation action, adsorbate–adsorbate lateral interaction, and complexation were involved in the spontaneous adsorption process. Physical electrostatic action was dominant in the initial stage, whereas chemical action was the driving force leading to adsorption equilibrium. It should be noted that after adsorption on the surface of MnPT, Cr(VI) reacted with some reducing functional groups (hydroxylamine-NH ) and was converted into Cr(III). The adsorption capacity declined by 12% after recycling five times. Understanding the adsorption mechanism might provide a technical basis for the procedural design of heavy metal adsorbents. This MnPT nanocomposite has been proven to be a low-cost, efficient, and promising adsorbent for removing heavy metal ions from wastewater.

关键词： MnO2-polyethylenimine-tannic acid composite     surface complexation formation model     Cu(II)     Cr(VI)     physicochemical mechanism    

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Occurrence of bisphenol A in surface and drinking waters and its physicochemical removal technologies

Liping LIANG,Jing ZHANG,Pian FENG,Cong LI,Yuying HUANG,Bingzhi DONG,Lina LI,Xiaohong GUAN

《环境科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 16-38 doi: 10.1007/s11783-014-0697-2

摘要： Bisphenol A (BPA), an endocrine disrupting compound, has caused wide public concerns due to its wide occurrence in environment and harmful effects. BPA has been detected in many surface waters and drinking water with the maximum concentrations up to tens of μg·L . The physicochemical technology options in eliminating BPA can be divided into four categories: oxidation, advanced oxidation, adsorption and membrane filtration. Each removal option has its own limitation and merits in removing BPA. Oxidation and advanced oxidation generally can remove BPA efficiently while they also have some drawbacks, such as high cost, the generation of a variety of transformation products that are even more toxic than the parent compound and difficult to be mineralized. Only few advanced oxidation methods have been reported to be able to mineralize BPA completely. Therefore, it is important not only to identify the major initial transformation products but also to assess their estrogenic activity relative to the parent compounds when oxidation methods are employed to remove BPA. Without formation of harmful by-products, physical separation methods such as activated carbon adsorption and membrane processes are able to remove BPA in water effluents and thus have potential as BPA removal technologies. However, the necessary regeneration of activated carbon and the low BPA removal efficiency when the membrane became saturated may limit the application of activated carbon adsorption and membrane processes for BPA removal. Hybrid processes, e.g. combining adsorption and biologic process or combining membrane and oxidation process, which can achieve simultaneous physical separation and degradation of BPA, will be highly preferred in future.

关键词： Bisphenol A (BPA)     occurrence     conventional oxidation     advanced oxidation     adsorption     membrane filtration    

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Synthesis, physicochemical characterizations and catalytic performance of Pd/carbon-zeolite and Pd/carbon-CeO

Zeinab JAMALZADEH, Mohammad HAGHIGHI, Nazli ASGARI

《环境科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 365-381 doi: 10.1007/s11783-013-0520-5

摘要： In this work, xylene removal from waste gas streams was investigated via catalytic oxidation over Pd/carbon-zeolite and Pd/carbon-CeO nanocatalysts. Activated carbon was obtained from pine cone chemically activated using ZnCl and modified by H PO . Natural zeolite of clinoptilolite was modified by acid treatment with HCl, while nano-ceria was synthesized via redox method. Mixed supports of carbon-zeolite and carbon-ceria were prepared and palladium was dispersed over them via impregnation method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller surface area (BET), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TG) techniques. Characterization of nanocatalysts revealed a good morphology with an average particle size in a nano range, and confirmed the formation of nano-ceria with an average crystallite size below 60 nm. BET analysis indicated a considerable surface area for catalysts (~1000 m ·g ). FTIR patterns demonstrated that the surface groups of synthesized catalysts are in good agreement with the patterns of materials applied in catalyst synthesis. The performance of catalysts was assessed in a low-pressure catalytic oxidation pilot in the temperature range of 100°C–250°C. According to the reaction data, the synthesized catalysts have been shown to be so advantageous in the removal of volatile organic compounds (VOCs), representing high catalytic performance of 98% for the abatement of xylene at 250°C. Furthermore, a reaction network is proposed for catalytic oxidation of xylene over nanocatalysts.

关键词： Pd/carbon-CeO2     Pd/carbon-zeolite     pine cone     ZnCl2     catalytic oxidation     xylene    

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腌制工艺对大菱鲆质构及理化性质的影响

王甜甜,李振兴,林洪,郭晓华

《中国工程科学》 2014年 第16卷 第9期   页码 64-68

摘要：

本文通过分析腌制大菱鲆质构及理化指标的变化，研究食盐浓度、腌制时间和腌制方式等对腌制大菱鲆品质的影响。结果表明：食盐浓度和腌制时间对腌制大菱鲆咀嚼度影响显著（P<0.05），对硬度、弹性和胶黏性无显著影响；腌制方式对腌制品的硬度、弹性和胶黏性影响显著（P<0.05），对咀嚼度无显著影响。在腌制过程中，食盐浓度每增加2 %，酸价降低1.03 mg/g，过氧化值平均降低0.1 g/100 g；腌制时间越长，酸价和过氧化值均有所升高；对感官评价来说，腌制时间有比较显著的影响（P<0.05）。由此可知，腌制工艺对大菱鲆产品的品质有显著的影响，本文通过分析各参数的影响，为进一步优化大菱鲆腌制工艺提供基础数据。

关键词： 腌制工艺     大菱鲆     质构     理化性质     感官评价    

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Comparative assessment of force, temperature, and wheel wear in sustainable grinding aerospace alloy using biolubricant

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0719-x

摘要： The substitution of biolubricant for mineral cutting fluids in aerospace material grinding is an inevitable development direction, under the requirements of the worldwide carbon emission strategy. However, serious tool wear and workpiece damage in difficult-to-machine material grinding challenges the availability of using biolubricants via minimum quantity lubrication. The primary cause for this condition is the unknown and complex influencing mechanisms of the biolubricant physicochemical properties on grindability. In this review, a comparative assessment of grindability is performed using titanium alloy, nickel-based alloy, and high-strength steel. Firstly, this work considers the physicochemical properties as the main factors, and the antifriction and heat dissipation behaviours of biolubricant in a high temperature and pressure interface are comprehensively analysed. Secondly, the comparative assessment of force, temperature, wheel wear and workpiece surface for titanium alloy, nickel-based alloy, and high-strength steel confirms that biolubricant is a potential replacement of traditional cutting fluids because of its improved lubrication and cooling performance. High-viscosity biolubricant and nano-enhancers with high thermal conductivity are recommended for titanium alloy to solve the burn puzzle of the workpiece. Biolubricant with high viscosity and high fatty acid saturation characteristics should be used to overcome the bottleneck of wheel wear and nickel-based alloy surface burn. The nano-enhancers with high hardness and spherical characteristics are better choices. Furthermore, a different option is available for high-strength steel grinding, which needs low-viscosity biolubricant to address the debris breaking difficulty and wheel clogging. Finally, the current challenges and potential methods are proposed to promote the application of biolubricant.

关键词： grinding     aerospace     difficult-to-machine material     biolubricant     physicochemical property     grindability    

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EXTRACTION AND EVALUATION OF EDIBLE OIL FROM SCHIZOCHYTRIUM SP. USING AN AQUEOUS ENZYMATIC METHOD

《农业科学与工程前沿（英文）》 2021年 第8卷 第4期   页码 623-634 doi: 10.15302/J-FASE -2021400

摘要：

Schizochytrium sp., a marine microalga, is a potential source of edible oil due to its short growth cycle and rapid lipid accumulation, especially of docosahexaenoic acid. An approach to isolate edible microalgal oil from Schizochytrium sp. using aqueous enzymatic extraction (AEE) was developed. Parameters were optimized by single-factor experiments followed by Box-Behnken design. Proteases were effective in extracting oil. The maximum free oil recovery (49.7%±0.58%) and total oil recovery (68.1%±0.94%) were obtained under optimum conditions of liquid-to-solid ratio of 4.8:1, a 2.5% enzyme concentration of papain and an extraction time of 2.2 h. There was a significant difference (P<0.05) in polyunsaturated fatty acid composition between microalgal oil obtained by AEE and by Soxhlet extraction, with the former having superior physiochemical properties and higher concentrations of bioactive components including total phenolic compounds and total tocopherols. These findings indicate a potential application of AEE for extraction of oil from Schizochytrium sp.

 

关键词： antioxidant activity / aqueous enzymatic extraction / edible microalgal oil / fatty acid composition / physicochemical properties    

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Sodium cellulose sulfate: A promising biomaterial used for microcarriers’ designing

Qing-Xi Wu, Yi-Xin Guan, Shan-Jing Yao

《化学科学与工程前沿（英文）》 2019年 第13卷 第1期   页码 46-58 doi: 10.1007/s11705-018-1723-x

摘要： Due to a worldwide focus on sustainable materials for human health and economy services, more and more natural renewable biomass are regarded as promising materials that could replace synthetic polymers and reduce global dependence on petroleum resources. Cellulose is known as the most abundant renewable polymer in nature, varieties of cellulose-based products have been developed and have gained growing interest in recent years. In this review, a kind of water-soluble cellulose derivative, i.e., sodium cellulose sulfate (NaCS) is introduced. Details about NaCS’s physicochemical properties like solubility, biocompatibility, biodegradability, degree of substitution, etc. are systematically elaborated. And promising applications of NaCS used as biomaterials for microcarriers’ designing, such as micro-cell-carriers, micro-drug-carriers, etc., are presented.

关键词： sodium cellulose sulfate     biomaterial     physicochemical properties     microcarriers    

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H2 对Pt-Ba-Ce /γ-Al2O3 催化剂NOx 存储和还原机理的影响研究 Article

王攀, 裔静, 孙川, 罗鹏, 雷利利

《工程（英文）》 2019年 第5卷 第3期   页码 568-575 doi: 10.1016/j.eng.2019.02.005

摘要：

本研究采用浸渍法制备了Pt-Ba-Ce/γ-Al2O3催化剂，利用实验评价了H2 对NSR（NOx storage and reduction）催化剂存储和还原机理的影响，并采用综合表征技术研究了Pt-Ba-Ce /γ-Al2O3 催化剂的理化性能。结果表明，透射电子显微镜（TEM）显示X 射线衍射（XRD）光谱中观察到的PtOx、CeO2 和BaCO3 峰很好地分散在γ-Al2O3 上，X 射线光电子能谱（XPS）检测到Ce3+ 和Ce4+ 之间的差异，Ce3+ 和Ce4+ 促进了活性氧在催化剂上的迁移。在NOx 完全存储- 还原实验中，NO2 产量的增加使NOx 的存储能力在250~350 ℃ 的温度范围内大大提高， 在350 ℃ 达到最大值315.3 μmol·g–1。在NOx 吸附和脱附循环实验中，随着H2暴露时间（30 s、45 s 和60 s）延长，NOx 的存储效率和转化率增加。当稀燃和富燃持续时间分别为240 s 和60 s 时，催化剂的NOx 最大转化率达到83.5%。适当增加H2量加速了硝酸盐或亚硝酸盐的分解，有利于NOx 存储-还原，并促进了下一循环NSR吸附位点的再生。

关键词： Pt–Ba–Ce/γ-Al2O3 催化剂，物理化学性质，NOx存储和还原，NOx 排放，H2 还原剂    

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Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 399-411 doi: 10.1007/s11465-010-0116-8

摘要： Conceptual design is the most critical and creative phase of design. Recently, increasing attention has been directed to supporting conceptual-level computer aided creative design and its theories and methodologies. Specifically, for conceptual design of mechanical products, this paper presents a novel function solving model for mechanical product design and highlights the importance of systematic synthesis to achieve creative design. Then it builds a framework as a function-effect-process-action- mechanisms (FEPAM) mapping process, which enables creative design on the basis of conceiving different action schemes. After that, several key points are elaborated including 1) representing and decomposition methods of functions and motion behaviors; 2) action scheme representing method based on network plan techniques; and 3) variation and creation methods based on action scheme transformations.

关键词： mechanism system creative design     process model     function solving model     process action procedure     mechanisms knowledge base     principle of mechanism system composition    

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Formation mechanism and modeling of surface waviness in incremental sheet forming

《机械工程前沿（英文）》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0679-1

摘要： Improving and controlling surface quality has always been a challenge for incremental sheet forming (ISF), whereas the generation mechanism of waviness surface is still unknown, which impedes the widely application of ISF in the industrial field. In this paper, the formation mechanism and the prediction of waviness are both investigated through experiments, numerical simulation, and theoretical analysis. Based on a verified finite element model, the waviness topography is predicted numerically for the first time, and its generation is attributed to the residual bending deformation through deformation history analysis. For more efficient engineering application, a theoretical model for waviness height is proposed based on the generation mechanism, using a modified strain function considering deformation modes. This work is favorable for the perfection of formation mechanism and control of surface quality in ISF.

关键词： surface waviness     incremental sheet forming     numerical simulation     formation mechanism     deformation history    

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Autogenous healing mechanism of cement-based materials

《结构与土木工程前沿（英文）》   页码 948-963 doi: 10.1007/s11709-023-0960-3

摘要： Autogenous self-healing is the innate and fundamental repair capability of cement-based materials for healing cracks. Many researchers have investigated factors that influence autogenous healing. However, systematic research on the autogenous healing mechanism of cement-based materials is lacking. The healing process mainly involves a chemical process, including further hydration of unhydrated cement and carbonation of calcium oxide and calcium hydroxide. Hence, the autogenous healing process is influenced by the material constituents of the cement composite and the ambient environment. In this study, different factors influencing the healing process of cement-based materials were investigated. Scanning electron microscopy and optical microscopy were used to examine the autogenous healing mechanism, and the maximum healing capacity was assessed. Furthermore, detailed theoretical analysis and quantitative detection of autogenous healing were conducted. This study provides a valuable reference for developing an improved healing technique for cement-based composites.

关键词： autogenous healing     cement-based materials     healing mechanism     aggregation effect    

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Optimal design of a linkage–cam mechanism-based redundantly actuated parallel manipulator

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 451-467 doi: 10.1007/s11465-021-0634-6

摘要： A redundantly actuated parallel manipulator (RAPM) with mixed translational and rotational degrees of freedom (DOFs) is challenged for its dimensionally homogeneous Jacobian modeling and optimal design of architecture. In this paper, a means to achieve redundant actuation by adding kinematic constraints is introduced, which reduces the DOFs of the end-effector (EE). A generic dimensionally homogeneous Jacobian is developed for this type of RAPMs, which maps the generalized velocities of three points on the EE to the joint velocities. A new optimization algorithm derived from this dimensionally homogeneous Jacobian is proposed for the optimal design of this type of RAPMs. As an example, this paper presents a spatial RAPM involving linkages and cam mechanisms. This RAPM has 4 DOFs and 6 translational actuations. The linkage lengths and the position of the universal joints of the RAPM are optimized based on the dimensionally homogeneous Jacobian.

关键词： redundant actuation     parallel manipulator     linkage–cam mechanism     Jacobian     optimal design    

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Cryogenic minimum quantity lubrication machining: from mechanism to application

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 649-697 doi: 10.1007/s11465-021-0654-2

摘要： Cutting fluid plays a cooling–lubrication role in the cutting of metal materials. However, the substantial usage of cutting fluid in traditional flood machining seriously pollutes the environment and threatens the health of workers. Environmental machining technologies, such as dry cutting, minimum quantity lubrication (MQL), and cryogenic cooling technology, have been used as substitute for flood machining. However, the insufficient cooling capacity of MQL with normal-temperature compressed gas and the lack of lubricating performance of cryogenic cooling technology limit their industrial application. The technical bottleneck of mechanical–thermal damage of difficult-to-cut materials in aerospace and other fields can be solved by combining cryogenic medium and MQL. The latest progress of cryogenic minimum quantity lubrication (CMQL) technology is reviewed in this paper, and the key scientific issues in the research achievements of CMQL are clarified. First, the application forms and process characteristics of CMQL devices in turning, milling, and grinding are systematically summarized from traditional settings to innovative design. Second, the cooling–lubrication mechanism of CMQL and its influence mechanism on material hardness, cutting force, tool wear, and workpiece surface quality in cutting are extensively revealed. The effects of CMQL are systematically analyzed based on its mechanism and application form. Results show that the application effect of CMQL is better than that of cryogenic technology or MQL alone. Finally, the prospect, which provides basis and support for engineering application and development of CMQL technology, is introduced considering the limitations of CMQL.

关键词： cryogenic minimum quantity lubrication (CMQL)     cryogenic medium     processing mode     device application     mechanism     application effect    

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Review on mechanism and process of surface polishing using lasers

Arun KRISHNAN, Fengzhou FANG

《机械工程前沿（英文）》 2019年 第14卷 第3期   页码 299-319 doi: 10.1007/s11465-019-0535-0

摘要： Laser polishing is a technology of smoothening the surface of various materials with highly intense laser beams. When these beams impact on the material surface to be polished, the surface starts to be melted due to the high temperature. The melted material is then relocated from the ‘peaks to valleys’ under the multidirectional action of surface tension. By varying the process parameters such as beam intensity, energy density, spot diameter, and feed rate, different rates of surface roughness can be achieved. High precision polishing of surfaces can be done using laser process. Currently, laser polishing has extended its applications from photonics to molds as well as bio-medical sectors. Conventional polishing techniques have many drawbacks such as less capability of polishing freeform surfaces, environmental pollution, long processing time, and health hazards for the operators. Laser polishing on the other hand eliminates all the mentioned drawbacks and comes as a promising technology that can be relied for smoothening of initial topography of the surfaces irrespective of the complexity of the surface. Majority of the researchers performed laser polishing on materials such as steel, titanium, and its alloys because of its low cost and reliability. This article gives a detailed overview of the laser polishing mechanism by explaining various process parameters briefly to get a better understanding about the entire polishing process. The advantages and applications are also explained clearly to have a good knowledge about the importance of laser polishing in the future.

关键词： laser polishing     surface roughness     process parameters     mechanism    

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Creation and integration mechanism of instrumentation flexible developing system

Xiaoli XU, Qiushuang LIU

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 235-240 doi: 10.1007/s11465-011-0122-5

摘要：

To solve many key technical problems during the development of modern instrumentation system integration and provide a new mode and fundamental technical equipment for the research and development (R&D) of modern instrumentation products, based on the concept of an instrumentation flexible developing system (IFDS), this paper discusses the creation and open flexible integration mechanism, perfects the integrated supporting environment and integrated system of the flexible interconnection, and constructs the new flexible integrated system. Based on the operation mechanism of the modern instrumentation developing system and the research and optimization of the rapid integration design method, the paper emphasizes the dynamic integrating method of multiple types of knowledge in a modern instrument R&D system, to effectively utilize the rich integrated resource and achieve rapid integration of the system. Applications show that the new IFDS can improve the integration level and efficiency of R&D of the modern instrumentation system, enforce the reliability of the system, shorten the R&D period, and reduce the development costs.

关键词： modern instrumentation developing     flexible interconnection     flexible integration mechanism     rapid integration system     dynamic integrating method    

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标题 作者 时间 类型 操作

Adsorption performance and physicochemical mechanism of MnO

Xiaoyan Deng, Luxing Wang, Qihui Xiu, Ying Wang, Hong Han, Dongmei Dai, Yongji Xu, Hongtao Gao, Xien Liu

期刊论文

Occurrence of bisphenol A in surface and drinking waters and its physicochemical removal technologies

Liping LIANG,Jing ZHANG,Pian FENG,Cong LI,Yuying HUANG,Bingzhi DONG,Lina LI,Xiaohong GUAN

期刊论文

Synthesis, physicochemical characterizations and catalytic performance of Pd/carbon-zeolite and Pd/carbon-CeO

Zeinab JAMALZADEH, Mohammad HAGHIGHI, Nazli ASGARI

期刊论文

腌制工艺对大菱鲆质构及理化性质的影响

王甜甜,李振兴,林洪,郭晓华

期刊论文

Comparative assessment of force, temperature, and wheel wear in sustainable grinding aerospace alloy using biolubricant

期刊论文

EXTRACTION AND EVALUATION OF EDIBLE OIL FROM SCHIZOCHYTRIUM SP. USING AN AQUEOUS ENZYMATIC METHOD

期刊论文

Sodium cellulose sulfate: A promising biomaterial used for microcarriers’ designing

Qing-Xi Wu, Yi-Xin Guan, Shan-Jing Yao

期刊论文

H2 对Pt-Ba-Ce /γ-Al2O3 催化剂NOx 存储和还原机理的影响研究

王攀, 裔静, 孙川, 罗鹏, 雷利利

期刊论文

Theory and method of mechanism system design

Huijun ZOU, Qinghua LIANG, Qing ZHANG

期刊论文

Formation mechanism and modeling of surface waviness in incremental sheet forming

期刊论文

Autogenous healing mechanism of cement-based materials

期刊论文

Optimal design of a linkage–cam mechanism-based redundantly actuated parallel manipulator

期刊论文

Cryogenic minimum quantity lubrication machining: from mechanism to application

期刊论文

Review on mechanism and process of surface polishing using lasers

Arun KRISHNAN, Fengzhou FANG

期刊论文

Creation and integration mechanism of instrumentation flexible developing system

Xiaoli XU, Qiushuang LIU

期刊论文