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Journal of Minerals and Materials Characterization and Engineering 2012年第3期11卷 321-333页

作者： N. Rajesh Mathivanan J. Jerald Department of Mechanical engg. P. E. S. Institute of Technology Bangalore - 85 India dept. of production engg. National Institute of Technology Tiruchirappalli - 15 India

This work presents the delamination resistance of woven glass fibre reinforced polymers (GFRP) and its influence on GFRP’s resistance to point impact. Two different types of laminates were fabricated by hand lay-up technique;(i) woven glass fibre epoxy matrix laminates and (ii) woven glass fibre epoxy matrix laminates with 3% graphite particulate fillers. End Notch Flexure (ENF) test was adopted for the measurement of delamination resistance. The two GFRPs laminates show similar mode II delamination resistance. At impact velocities between 2.215 and 4.429 m/sec, the GFRP developed a smaller damage size than the graphite-based GFRP laminates, indicating higher impact toughness. Difference of the impact resistance between the two GFRPs is mainly on the impact damage size developed. The total energy absorbed during the impact remains the same, which is independent of mode II delamination resistance of the GFRP. The history of relevant dynamic and energetic quantities, both to synthesize the dependency of the energy parameters and force threshold values on the impact velocity are discussed.

关键词： Polymer matrix composite Fibre Laminates Impact toughness.

Influence of Coolant on Cutting Tool Performance

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Journal of Materials Science & Technology 1997年第3期13卷 199-205页

作者： K.H.W.Seah and X.Li(dept. of Mechanical and production Engineering, National University of Singapore, 10 Kent Ridge Crescent,Singapore 119260) dept. of Mechanical and production Engineering National University of Singapore 10 Kent Ridge Crescent Singapore 119260 Singapore

This paper reports a Study carried out to substantiate or refute the belief that when coolant is applied, the cutting performance is actually improved. Experiments on cutting forces and chip geometry were conducted in which AISI 1050 Steel was machined by turning using P30 uncoated tungsten carbide tools. Experiments were performed on a CNC Okuma LH35-N lathe undermachining conditions commonly used in workshops in Singapore and many other parts of the world.

关键词： Tool Influence of Coolant on Cutting Tool Performance

An Integrated Die Casting Design System

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厦门大学学报（自然科学版） 2002年第S1期41卷 208-209页

作者： Y K Woon K S Lee dept. of Mechanical and production Engineering National University of SingaporeDept. of Mechanical and Production Engineering National University of Singapore SingaporeSingapore

Die casting process is one of the prime options for m anufacturing precisely dimensioned, sharply defined metal parts. The design of d ie casting dies comprises several stages and entails a large amount of time. Tra ditionally, the different stages of the die design were not integrated but exist as separate entities. Moreover, recurring modifications or even redesigns are r equired due to the complexity in achieving an accurate initial die design. As a result, die design is usually time-consuming and costly with respect to resourc es. The die casting industry will greatly benefit if proper application software are developed that integrates the different die design stages and allows editin g of die design as and when needed. Hence it is imperative to create an integrat ed die design system that shortens the die design time. This paper presents a research that establishes a prototype of an integrated die design system. It is developed using the commercial SolidWorks CAD system and n amed DiWorks. The aim of building the system on a commercial CAD system is to ut ilise the resources and features of the CAD system to speed up the die design pr ocess. DiWorks consists of six distinct modules: Project Manager, Cavity Insert Builder, Gating System Constructor, Die Base Designer, Ejector System Constructo r and Standard Components Library. Through these six modules, the die designer c an create a complete die casting die beginning from a product part model. It is a user-friendly system that allows both experienced and novice die designers to easily accomplish the task of die design. The practical goal of this research is twofold: to develop a system that integra tes the die design process and at the same time facilitates the editing of d ie design during or after the course of the design process. The research approac h includes (i) parametric design, (ii) feature-based design (iii) system modeli ng and implementation. Parametric design deals with variable dimensions as cont

关键词： integrated die design system parametric design feature-based design

Numerical simulation and experimental validation of arc welding of DMR-249A steel

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Defence Technology（防务技术） 2016年第4期12卷 305-315页

作者： Rishi PAMNANI M. VASUDEVAN T. JAYAKUMAR R VASANTHARAJA K.C. GANESH Prototype Training Centre Kalpakkam Tamil Nadu 603 127 India IGCAR Tamil Nadu 603 102 India Metallurgical and Materials engg.dept NIT Warangal 506 004 India dept.of Mech engg NITT Tiruchirappalli 620 015 India

The thermo-mechanical attributes of DMR-249 A steel weld joints manufactured by shielded metal arc welding(SMAW) and activated gas tungsten arc welding(A-GTAW) processes were studied using Finite Element Model(FEM) simulation. The thermal gradients and residual stresses were analyzed with SYSWELD software using double ellipsoidal heat source distribution model. The numerically estimated temperature distribution was validated with online temperature measurements using thermocouples. The predicted residual stresses profile across the weld joints was compared with the values experimentally measured using non-destructive techniques. The measured and predicted thermal cycles and residual stress profile was observed to be comparable. The residual stress developed in double sided A-GTAW joint were marginally higher in comparison to five pass SMAW joint due to phase transformation associated with high heat input per weld pass for A-GTAW process. The present investigations suggest the applicability of numerical modeling as an effective approach for predicting the thermo-mechanical properties influenced by welding techniques for DMR-249 A steel weld joints. The tensile, impact and micro-hardness tests were carried to compare the *** benefits of high productivity and savings of labor and cost associated with A-GTAW compared to SMAW process, the minor variation in residual stress build up of A-GTAW joint can be neglected to develop A-GTAW as qualified alternative welding technique for DMR-249 A steel.? 2016 China Ordnance Society. production and hosting by Elsevier B.V. All rights reserved.

关键词： DMR-249A A-GTAW SMAW FEM SYSWELD Thermo-mechanical Simulation

Injectable Nanorobot-Hydrogel Superstructure for Hemostasis and Anticancer Therapy of Spinal Metastasis

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NANO-MICRO LETTERS 2024年第1期16卷 1-22页

作者： Chen, Qing Yan, Miao Hu, Annan Liang, Bing Lu, Hongwei Zhou, Lei Ma, Yiqun Jia, Chao Su, Dihan Kong, Biao Hong, Wei Jiang, Libo Dong, Jian Fudan Univ Dept Orthopaed Surg Zhongshan Hosp Shanghai 200032 Peoples R China Fudan Univ State Key Lab Mol Engn Polymers Shanghai 200438 Peoples R China Fudan Univ Zhongshan Hosp Dept Orthopaed Surg Wusong Branch Shanghai 200940 Peoples R China Fudan Univ Dept Chem Shanghai 200438 Peoples R China Natl Univ Singapore Yong Loo Lin Sch Med Dept Surg 1E Kent Ridge Rd Singapore 119228 Singapore Fudan Univ Huadong Hosp Dept Geriatr & Gerontol Shanghai 200438 Peoples R China

Site-selective superassembly was used to synthesize a nanorobot with bionic rod-shaped head/hollow tail structure, exhibiting strong photothermal effect, high drug loading capacity, precise and controlled drug release, and excellent *** regenerated silk fibroin (RSF) nanofibril hydrogels were developed via simple sonication, offering significant production, structural, and performance ***/thrombin (Thr)/RSF nanofibril hydrogels reduced intraoperative bleeding of hepatocellular carcinoma (HCC) spinal metastasis, provided starvation embolization, and prevented post-surgery ***/Thr/RSF nanofibril hydrogels inhibited blood supply to residual tumors and reduced neovascularization, inhibiting post-surgery HCC spinal metastasis recurrence. AbstractSurgery remains the standard treatment for spinal metastasis. However, uncontrolled intraoperative bleeding poses a significant challenge for adequate surgical resection and compromises surgical outcomes. In this study, we develop a thrombin (Thr)-loaded nanorobot-hydrogel hybrid superstructure by incorporating nanorobots into regenerated silk fibroin nanofibril hydrogels. This superstructure with superior thixotropic properties is injected percutaneously and dispersed into the spinal metastasis of hepatocellular carcinoma (HCC) with easy bleeding characteristics, before spinal surgery in a mouse model. Under near-infrared irradiation, the self-motile nanorobots penetrate into the deep spinal tumor, releasing Thr in a controlled manner. Thr-induced thrombosis effectively blocks the tumor vasculature and reduces bleeding, inhibiting tumor growth and postoperative recurrence with Au nanorod-mediated photothermal therapy. Our minimally invasive treatment platform provides a novel preoperative therapeutic strategy for HCC spinal metastasis effectively controlling intraoperative bleeding and tumor growth, with potentially reduced surgical complications and enhanced operative outcomes.

关键词： Silk fibroin Nanofibril hydrogels Nanorobots Thrombin Spinal metastasis SILK FIBROIN HYDROGELS BLOOD-LOSS EMBOLIZATION DISEASE SURGERY

Sustainable bio-energy generation via the conversion of spent wash using dual chamber microbial fuel cell

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WASTE DISPOSAL & SUSTAINABLE ENERGY 2024年第2期6卷 219-231页

作者： Jatoi, Abdul Sattar Ahmed, Jawad Bhutto, Afaque Ahmed Shaikh, Muhammad Shuaib Dawood Univ Engn & Technol Karachi Dept Chem Engn Sindh Pakistan Changzhou DUBO Polymer Co Ltd Changzhou 213002 Peoples R China Univ Larkano Dept Basic Sci & Related Studies Sindh Pakistan Mehran Univ Engn & Technol Jamshoro Dept Chem Engn Sindh Pakistan

Microbial fuel cells (MFCs) are innovative devices that combine microbial processes with electrochemical reactions to convert organic matter in wastewater into electricity while simultaneously treating the wastewater. One such application is the treatment of spent wash, a highly polluting effluent generated from the distillery industry after crude mesh is separated into ethanol and spent wash. Spent wash, also known as distillery effluent or stillage, is a highly challenging wastewater treatment method due to its high chemical oxygen demand (COD), biological oxygen demand (BOD), and total dissolved solids (TDS). These characteristics make it a complex and polluting industrial effluent that requires specialized treatment processes to reduce its environmental impact effectively. However, MFCs have shown promise in treating spent wash, as they can utilize the organic matter in wastewater as a fuel source for microbial growth as well as for electricity generation. For the treatment of spent wash, Saccharomyces cerevisiae sp. was used as a biocatalyst along with 340 mol/L potassium ferricyanide in the cathode chamber and 170 mol/L methylene blue in the anode as a mediator. All tests were conducted by balancing a one-liter volume for power production from spent wash in MFC with the optimal conditions of 10% agarose, pH 8.5, 300 mL/min of aeration in the cathode chamber, and 40% (in weight) substrate concentration. At an ideal concentration, the maximum current and power density are roughly 53.41 mA/m2 and 72.22 mW/m2, respectively. For each litre of processed spent wash, a maximum voltage of 850 mV (4.5 mA) was obtained. Amazingly, 91% of COD and BOD were removed from the effluent MFC. These findings show that MFCs are capable of producing electricity and efficiently removing COD from wasted wash at the same time.

关键词： Microbial fuel cell Chemical oxygen demand Biological oxygen demand Current density Power density Spent wash ELECTRICITY-GENERATION WATER TREATMENT POWER-GENERATION HYDROGEN IDENTIFICATION

A framework for risk analysis of the shellfish aquaculture:The case of the Mediterranean mussel farming in Greece

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Aquaculture and Fisheries 2023年第4期8卷 375-384页

作者： John A.Theodorou Ioannis Tzovenis Department of Animal production Fisheries&AquacultureUniversity of PatrasMesolonghi30200Greece Laboratory of Ecology&Systematics Biology Dept.University of AthensPanepistimioupolisZografou15784Greece

Mediterranean mussel farming in Greece developed considerably during the last 40 years reaching a gross commodity product up to the limits of the country’s production capacity(35–40,000 tonnes/year).Despite the achievements in the sector’s growth,little or no effort has been attributed yet to risk assessment and moreover to risk management of the *** present effort aims at developing a working framework for the shellfish aquaculture of Greece to be used as a tool by the sector’s decision makers to advance strategies for risk elimination or *** work was based on a generic risk management standard tool,the Joint Australian and New Zealand Risk Management Standard AS/NZS ISO 31000:2009 that has been adapted to the specific national characteristics of all levels of the mussel farming business-activities and the industry *** framework supported by data sets regarding development,production,profits and losses,retrieved by surveys through distributed questionnaires or interviews during site-visits,as well as by collecting data from national and international *** input covered technology,farm size,farmer risk-attitude,risk-management strategies,risk-perceptions and socioeconomic *** risks and risk management options were identified providing aid for remediation risk policies to the stakeholders.

关键词： ISO 31000 Risk analysis Mediterranean mussel farming Aquaculture insurance

Effect of Mg addition on mechanical and thermoelectrical properties of Al-Al_2O_3 nanocomposite

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Transactions of Nonferrous Metals Society of China 2016年第11期26卷 2810-2817页

作者： A.WAGIH Mechanical Design and production dept Faculty of Engineering Zagazig University P. O. Box 44519 Zagazig Sharkia Egypt

The effects of Mg addition on mechanical thermo-electrical properties of ***/5%Al2O3 nanocomposite with differentMg contents （0, 5%, 10% and 20%） produced by mechanical alloying were studied. Scanning electron microscopy analysis （SEM）,X-ray diffraction analysis （XRD） and transmission electron microscopy （TEM） were used to characterize the produced powder. Theresults show that addition of Mg forms a predominant phase （*** solid solution）. By increasing the mass fraction of Mg, thecrystallite size decreases and the lattice strain increases which results from the atomic penetration of Mg atoms into the substitutionalsites of Al lattice. The microhardness of the composite increases with the increase of the Mg content. The thermal and electricalconductivities increase linearly with the temperature increase in the inspected temperature range. Moreover, the thermalconductivity increases with the increase of Mg content.

关键词： Al.Al2O3 nanocomposite Mg mechanical alloying microhardness thermoelectrical properties

3D printing for ultra-precision machining: current status, opportunities, and future perspectives

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FRONTIERS OF MECHANICAL ENGINEERING 2024年第4期19卷 23-23页

作者： He, Tao Yip, Wai Sze Yan, Edward Hengzhou Tang, Jiuxing Rehan, Muhammad Teng, Long Wong, Chi Ho Sun, Linhe Zhang, Baolong Guo, Feng Zhang, Shaohe To, Suet Hong Kong Polytech Univ Dept Ind & Syst Engn State Key Lab Ultraprecis Machining Technol Hong Kong Peoples R China Hong Kong Polytech Univ Dept Ind & Syst Engn Hong Kong Peoples R China Hong Kong Univ Sci & Technol Dept Phys Hong Kong Peoples R China Cent South Univ Sch Geosci & Infophys Changsha 410083 Peoples R China

Additive manufacturing, particularly 3D printing, has revolutionized the manufacturing industry by allowing the production of complex and intricate parts at a lower cost and with greater efficiency. However, 3D-printed parts frequently require post-processing or integration with other machining technologies to achieve the desired surface finish, accuracy, and mechanical properties. Ultra-precision machining (UPM) is a potential machining technology that addresses these challenges by enabling high surface quality, accuracy, and repeatability in 3D-printed components. This study provides an overview of the current state of UPM for 3D printing, including the current UPM and 3D printing stages, and the application of UPM to 3D printing. Following the presentation of current stage perspectives, this study presents a detailed discussion of the benefits of combining UPM with 3D printing and the opportunities for leveraging UPM on 3D printing or supporting each other. In particular, future opportunities focus on cutting tools manufactured via 3D printing for UPM, UPM of 3D-printed components for real-world applications, and post-machining of 3D-printed components. Finally, future prospects for integrating the two advanced manufacturing technologies into potential industries are discussed. This study concludes that UPM is a promising technology for 3D-printed components, exhibiting the potential to improve the functionality and performance of 3D-printed products in various applications. It also discusses how UPM and 3D printing can complement each other.

关键词： ultra-precision machining 3D printing additive manufacturing future perspectives start-of-the-art-review METAL-MATRIX COMPOSITES POTENTIAL DIRECTIONS SURFACE GENERATION CURRENT CHALLENGES DEPOSITION FABRICATION TOOL VIBRATION PERFORMANCE TECHNOLOGY

A Study of Aquifer Thermal Energy Storage:Numerical Simulation of Thermal Storage Experiments in Shanghai

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 297-311页

作者： Xue Yuqun dept.of Earth Sciences, Nangjing University, Nanjing Xie Chunhong dept.of Mathematics, Nangjing University, Nanjing and Li Qinfen Shanghai Environmental Geology Center, Shanghai dept. of Earth Sciences Nangjing University Nanjing China

This paper proposes a 3-D convection-heat dispersion model for a confined aquifer. The governing equation of the model contains not only the traditional convection and conduction terms, but also a heat dispersion term which has often been overlooked in many similar researches. The model is used to describe a series of aquifer thermal energy storage experiments conducted at the Shanghai experimental site, including single-well injection, double-well injection/production and multiple-well injection/prodution tests. The simulated temperatures agree very well with the field data (relative error: 2.8%-4.5%). A detailed description of the model is given, followed by a detailed comparison of simulated and measured temperature distributions.

关键词： A Study of Aquifer Thermal Energy Storage Simulation