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Edge preparation methods for cutting tools: a review

《机械工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0766-y

摘要: Edge preparation can remove cutting edge defects, such as burrs, chippings, and grinding marks, generated in the grinding process and improve the cutting performance and service life of tools. Various edge preparation methods have been proposed for different tool matrix materials, geometries, and application requirements. This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development. First, typical edge characterization methods, which associate the microgeometric characteristics of the cutting edge with cutting performance, are briefly introduced. Then, edge preparation methods for cutting tools, in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining, are discussed. New edge preparation methods are explored on the basis of existing processing technologies, and the principles, advantages, and limitations of these methods are systematically summarized and analyzed. Edge preparation methods are classified into two categories: mechanical processing methods and nontraditional processing methods. These methods are compared from the aspects of edge consistency, surface quality, efficiency, processing difficulty, machining cost, and general availability. In this manner, a more intuitive understanding of the characteristics can be gained. Finally, the future development direction of tool edge preparation technology is prospected.

关键词: edge preparation method     preparation principle     cutting edge geometry     edge characterization     tool performance    

Cutting edge preparation of microdrills by shear thickening polishing for improved hole quality in electronic

《机械工程前沿(英文)》 2024年 第19卷 第2期 doi: 10.1007/s11465-024-0786-2

摘要: Printed circuit boards (PCBs) are representative composite materials, and their high-quality drilling machining remains a persistent challenge in the industry. The finishing of the cutting edge of a microdrill is crucial to drill performance in machining fine-quality holes with a prolonged tool life. The miniature size involving submicron scale geometric dimensions, a complex flute shape, and low fracture toughness makes the cutting edge of microdrills susceptible to breakage and has been the primary limiting factor in edge preparation for microdrills. In this study, a newly developed cutting edge preparation method for microdrills was tested experimentally on electronic printed circuit boards. The proposed method, namely, shear thickening polishing, limited the cutting edge burrs and chipping on the cutting edge, and this in turn transformed the cutting edge’s radius from being sharp to smooth. Moreover, the edge–edge radius could be regulated by adjusting the processing time. PCB drilling experiments were conducted to investigate the influence of different cutting edge radii on wear, hole position accuracy, nail head value, and hole wall roughness. The proposed approach showed 20% enhancement in hole position accuracy, 33% reduction in the nail head value, and 19% reduction in hole wall roughness compared with the original microdrill. However, a threshold is needed; without it, excessive shear thickening polishing will result in a blunt edge, which may accelerate the wear of the microdrill. Wear was identified as the primary factor that reduced hole quality. The study indicates that in printed circuit board machining, microdrills should effectively eliminate grinding defects and maintain the sharpness of the cutting edge as much as possible to obtain excellent drilling quality. Overall, shear thickening polishing is a promising method for cutting edge preparation of microdrills. Further research and optimization can lead to additional improvements in microdrill performance and contribute to the continued advancement of printed circuit board manufacturing.

关键词: microdrill     shear thickening polishing     cutting edge preparation     electronic printed circuit boards     hole quality    

The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 457-463 doi: 10.1007/s11783-013-0512-5

摘要: Selective catalytic reduction of NO by H in the presence of oxygen has been investigated over Pt/Al O catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by H or H then followed by O is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/Al O pre-treated by H or pretreated by H then followed by O can contribute to the formation of NO , which then promotes the reaction to proceed at low temperatures.

关键词: NOx reduction     Pt/Al2O3     preparation condition     H2-SCR    

Selective preparation for biofuels and high value chemicals based on biochar catalysts

《能源前沿(英文)》 2023年 第17卷 第5期   页码 635-653 doi: 10.1007/s11708-023-0878-4

摘要: The reuse of biomass wastes is crucial toward today’s energy and environmental crisis, among which, biomass-based biochar as catalysts for biofuel and high value chemical production is one of the most clean and economical solutions. In this paper, the recent advances in biofuels and high chemicals for selective production based on biochar catalysts from different biomass wastes are critically summarized. The topics mainly include the modification of biochar catalysts, the preparation of energy products, and the mechanisms of other high-value products. Suitable biochar catalysts can enhance the yield of biofuels and higher-value chemicals. Especially, the feedstock and reaction conditions of biochar catalyst, which affect the efficiency of energy products, have been the focus of recent attentions. Mechanism studies based on biochar catalysts will be helpful to the controlled products. Therefore, the design and advancement of the biochar catalyst based on mechanism research will be beneficial to increase biofuels and the conversion efficiency of chemicals into biomass. The advanced design of biochar catalysts and optimization of operational conditions based on the biomass properties are vital for the selective production of high-value chemicals and biofuels. This paper identifies the latest preparation for energy products and other high-value chemicals based on biochar catalysts progresses and offers insights into improving the yield of high selectivity for products as well as the high recyclability and low toxicity to the environment in future applications.

关键词: biomass     biochar catalysts     biofuels     high chemicals    

A highly efficient methodology for the preparation of

Yongxin Zhang, Shucheng Wang, Yaodong Huang

《化学科学与工程前沿(英文)》 2021年 第15卷 第3期   页码 679-686 doi: 10.1007/s11705-020-1979-9

摘要: A convenient and highly efficient method is described for the synthesis of -methoxycarbazole derivatives, including those with sterically demanding, benzannulated, or strongly electron-donating or -withdrawing substituents. Various -methoxycarbazole derivatives were directly prepared in good-to-moderate yields by the Pd (dba) CHCl /9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene-catalyzed reactions of the corresponding dibromobiphenyl compounds and methoxya-mine. Based on this methodology, the first total synthesis of 3,3′-[oxybis(methylene)]bis(9-methoxy-9 -carbazole), an antimicrobial dimeric carbazole alkaloid previously isolated from the stem bark of , was achieved in 18% yield over seven steps from 1,2-dibromobenzene.

关键词: N-methoxyl carbazole     dimeric N-methoxyl carbazole     alkaloid     total synthesis     double N-arylation of methoxyamine    

Kinetics of pozzolanic reaction for preparation of flue gas desulfurizer from fly ash and Ca(OH)2

WANG Jingang, HU Jinbang, WANG Daobin, DUAN Zhenya

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 266-270 doi: 10.1007/s11705-007-0048-y

摘要: A kinetic model of the pozzolanic reaction for the preparation of flue gas desulfurizers from fly ash and Ca(OH) was deduced on the basis of solid phase reaction kinetic theory. Kinetic expressions and parameters were obtained and verified by experiment. A comparison of calculated results with experimental results showed that precision in kinetic expressions was good. The apparent reaction rate constants of the pozzolanic reaction could be raised by increasing the specific surface area of fly ash and the hydration temperature, and by using a suitable additive.

关键词: comparison     calculated     pozzolanic reaction     precision     preparation    

preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

《化学科学与工程前沿(英文)》 2023年 第17卷 第7期   页码 906-917 doi: 10.1007/s11705-022-2273-9

摘要: The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 μm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词: Ag@AgCl     biological veins     photocatalytic activity     recyclability    

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

《环境科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 482-487 doi: 10.1007/s11783-007-0077-2

摘要: Catalytic ozonation of aqueous solutions of oxalic acid was examined in the presence of graphite-supported platinum catalysts. The catalytic activity of graphite was significantly enhanced by loading platinum. The removal efficiency of oxalic acid was 3.0%, 47.6% and 99.3% for ozonation alone, graphite catalytic ozonation and Pt/graphite catalytic ozonation in 30 min under the experimental condition, respectively. The influence of support pretreatment, solvent, impregnation time, platinum loading amount and reduction temperature on the activity of Pt/graphite catalyst was investigated. The pretreatment of graphite support had no effect on activity improvement of Pt/graphite catalyst. Solvent and impregnation time also had no great effect on the activity. Platinum loading amount and reduction temperature influenced the catalyst activity significantly. The optimal catalytic performance of Pt/graphite was obtained when 1.0% platinum loading and 623 K of reduction temperature was adopted. The Pt/graphite catalyst was used for five times with no significant decrease in its activity and more than 90% oxalic acid removal was obtained.

Preparation and application of magnetic microsphere carriers

ZHANG Bo, XING Jianmin, LIU Huizhou

《化学科学与工程前沿(英文)》 2007年 第1卷 第1期   页码 96-101 doi: 10.1007/s11705-007-0019-3

摘要: Magnetic microsphere carriers have received considerable attention, primarily because of their wide applications in the fields of biomedicine and bioengineering. In this paper, preparation methods, surface modification and application of magnetic carriers are reviewed. Emphasis will be placed on recent biological and biomedical developments and trends such as enzyme immobilization, cell isolation, protein purification, target drugs and DNA separation.

关键词: microsphere     biomedicine     DNA     purification     preparation    

Reactive extraction for preparation of hydrogen peroxide under pressure

CHENG Yongxi, LI Hongtao, WANG Li, LÜ Shuxiang

《化学科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 335-340 doi: 10.1007/s11705-008-0042-z

摘要: The preparation of hydrogen peroxide from anthrahydroquinone by reactive extraction was investigated. The integration process of oxidation of anthrahydroquinone by air and extraction of hydrogen peroxide from the organic phase with water was carried out in a sieve plate column under pressure. The conversion of anthrahydroquinone increased with increasing pressure resulting in an increase of hydrogen peroxide concentration in the aqueous phase. However, no change in extraction efficiency of hydrogen peroxide was observed. A mathematical model for gas-liquid-liquid reactive extraction was established. In the model, the effects of pressure and gas superficial velocity on reaction were considered. With increasing gas superficial velocity, the conversion of anthrahydroquinone increased, and the fraction of hydrogen peroxide extracted reached a plateau with a maximum of 72.94%. However, both the conversion of anthrahydroquinone and the fraction of hydrogen peroxide extracted decreased with increasing organic phase superficial velocity.

Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 819-837 doi: 10.1007/s11705-021-2122-2

摘要: With the increasing demand for high-performance and safe fuels in aerospace propulsion systems, gelled fuels have attracted increasing attention. Because of their unique structure, gelled fuels exhibit the advantages of both solid and liquid fuels, such as high energy density, controllable thrust and storage safety. This review provides an overview on design, preparation and performance characterization of gelled fuels. The composition, preparation process and gelation mechanism of gelled high-energy-density fuels are described. Considering these aspects, the rheology and flow behavior of gelled fuels is summarized in terms of the shear thinning property, dynamic viscoelasticity and thixotropy. Moreover, the progress of atomization of gelled fuels is reviewed with a focus on the effect of atomizing nozzles. In addition, the experiments and theoretical models of single droplet combustion and combustor combustion are described. Finally, research directions for the development and application of gelled fuels are suggested.

关键词: gelled fuels     high-energy-density fuels     rheological properties     atomization     combustion    

Preparation and characterization of lithium

Chang WANG,Yanlong ZHAI,Xi WANG,Ming ZENG

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 471-477 doi: 10.1007/s11705-014-1449-3

摘要: Lithium -MnO ion-sieves were prepared from spinel LiMn O via treatment with nitric acid. The LiMn O was synthesized by a solid state reaction between LiOH·H O and MnO . The effects of the calcination time and temperature on the preparation of the LiMn O precursor and the lithium ion-sieve were investigated. In addition, the Li extraction ratio, the Mn dissolving ratio and the adsorption properties of the lithium ion-sieve were all measured. The lithium ion-sieve had a high exchange capacity and was selective for Li . Specifically, at pH= 13, the ion exchange capacity of Li was 30.9 mg/g in 10 mmol/L LiCl solution and the lithium extraction ratio and manganese dissolving ratio were 95% and 25%, respectively.

关键词: lithium ion-sieve     solid state reaction     adsorption     LiMn2O4    

Preparation and adsorption performances of mesopore-enriched bamboo activated carbon

WANG Yuxin, LIU Congmin, ZHOU Yaping

《化学科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 473-477 doi: 10.1007/s11705-008-0081-5

摘要: Activated carbon with high specific surface area and considerable mesopores was prepared from bamboo scraps by phosphoric acid activation. The effect of activation conditions was studied. Under the conditions of impregnating bamboo with 80% HPO at 80°C for 9 days and activation at 500°C for 4 h, the prepared activated carbon had the highest mesopore volume of 0.67 cm/g, a specific surface area of 1567 m/g, and the mesopore ratio reached 47.18%. The study on adsorption isotherms of CH, CO, N and O on the activated carbon were carried out at 298 K. The considerable difference in the adsorption capacity between CO and the other gases was observed, which would be of interest for the adsorptive separation/purification of gaseous CO from its mixtures, especially from mixtures with N and/or O.

关键词: mesopore volume     gaseous     considerable difference     adsorption capacity     activation    

Nanostructured hollow spheres of hydroxyapatite: preparation and potential application in drug delivery

Xiaojing ZHANG, Weixin ZHANG, Zeheng YANG, Zhao ZHANG

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 246-252 doi: 10.1007/s11705-012-1299-9

摘要: A solvothermal method has been successfully used to prepare nanostructured hydroxyapatite (HA) hollow spheres with average diameters of about 500 nm and shell thicknesses of about 100 nm in a glycerin/water mixed solvent. Transmission electron microscopy (TEM) and field-emission scanning electron microscopy (FESEM) images show that the shells of the HA hollow spheres are actually composed of nanosheets with thicknesses of about 10 nm. By tuning the glycerin/water volume ratio, two other kinds of HA solid spheres with average diameters of about 6 or 20 μm were assembled from nanoflakes. The properties of the different kinds of spheres as drug delivery carriers were evaluated. Ibuprofen (IBU) was chosen as the model drug to load into the HA samples. The nanostructured HA samples showed a slow and sustained release of IBU. The HA hollow spheres exhibited a higher drug loading capacity and more favorable release properties than the HA solid spheres and thus are very promising for controlled drug release applications.

关键词: hydroxyapatite     hollow spheres     synthesis     drug release    

Preparation and characterization of

Chunhua XU, Dandan CHENG, Baoyu GAO, Zhilei YIN, Qinyan YUE, Xian ZHAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 455-462 doi: 10.1007/s11783-010-0275-1

摘要: Batch adsorption experiments were conducted to explore the adsorption of Cr(VI) in aqueous solutions by -FeOOH-coated sand. We investigated the key factors which affected the adsorption process such as adsorbent dosage, initial pH, initial Cr(VI) ion concentration, contact time and temperature. The uptake of Cr(VI) was very rapid and 44.3%, 51.6%, 58.9% of the adsorption happened during the first 180 minutes at 293K, 303K and 313K, respectively. The pseudo-second-order rate equation successfully described the adsorption kinetics. To study the adsorption isotherm, two equilibrium models, the Langmuir and Freundlich isotherms, were adopted. At 293K, 303K and 313K, the adsorption capacities obtained from the Langmuir isotherm were 0.060, 0.070 and 0.076 mg Cr(VI) per gram of the adsorbent, respectively. Thermodynamic parameters such as the change of energy, enthalpy and entropy were calculated using the equilibrium constants. The negative value of and the positive value of showed that the adsorption of Cr(VI) in aqueous solutions by -FeOOH-coated sand was spontaneous, endothermic and occurred by physisorption.

关键词: β-FeOOH-coated sand     Cr(VI)     adsorption     isotherm     kinetics    

标题 作者 时间 类型 操作

Edge preparation methods for cutting tools: a review

期刊论文

Cutting edge preparation of microdrills by shear thickening polishing for improved hole quality in electronic

期刊论文

The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

期刊论文

Selective preparation for biofuels and high value chemicals based on biochar catalysts

期刊论文

A highly efficient methodology for the preparation of

Yongxin Zhang, Shucheng Wang, Yaodong Huang

期刊论文

Kinetics of pozzolanic reaction for preparation of flue gas desulfurizer from fly ash and Ca(OH)2

WANG Jingang, HU Jinbang, WANG Daobin, DUAN Zhenya

期刊论文

preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

期刊论文

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

期刊论文

Preparation and application of magnetic microsphere carriers

ZHANG Bo, XING Jianmin, LIU Huizhou

期刊论文

Reactive extraction for preparation of hydrogen peroxide under pressure

CHENG Yongxi, LI Hongtao, WANG Li, LÜ Shuxiang

期刊论文

Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

期刊论文

Preparation and characterization of lithium

Chang WANG,Yanlong ZHAI,Xi WANG,Ming ZENG

期刊论文

Preparation and adsorption performances of mesopore-enriched bamboo activated carbon

WANG Yuxin, LIU Congmin, ZHOU Yaping

期刊论文

Nanostructured hollow spheres of hydroxyapatite: preparation and potential application in drug delivery

Xiaojing ZHANG, Weixin ZHANG, Zeheng YANG, Zhao ZHANG

期刊论文

Preparation and characterization of

Chunhua XU, Dandan CHENG, Baoyu GAO, Zhilei YIN, Qinyan YUE, Xian ZHAO

期刊论文