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Materials Sciences and Applications 2011年第7期2卷 810-816页

作者： Genevive C. Onuegbu Isaac O. Igwe Department of Polymer and Textile Engineering Federal University of Technology Owerri Nigeria.

Polypropylene composites of snail shell powder were prepared at filler contents, 0 to 40 wt%. The particle sizes of the snail shell powder investigated were 0.150, 0.30, and 0.42 μm. Talc, of particle size, 0.150 μm was used as the reference filler. The polypropylene composites were prepared in an injection moulding machine and the resulting composites were extruded as sheets. Some mechanical and end-use properties of the prepared composites were determined. Results showed that the snail shell powder improved the tensile modulus, flexural strength, and impact strength of polypropylene and these properties increased with increases in the filler content and decreases in the filler particle size. The elongation at break of the composites was however observed to decrease with increases in the filler content, and particle size. The elongation at break of talc filled polypropylene was zero, an indication of the brittle nature of polypropylene composites of talc. The hardness, water sorption (24-hr) and specific gravity of the composites were found to increase with increases in the filler content, and decreases in the filler particle size. The level of water absorbed by snail shell powder composites of polypropylene is considerably higher than that of talc filled polypropylene. The flame retardant properties of the prepared composites were however found to decrease with increases in the filler content, and particle size. Generally, snail shell powder was found to show greater property improvement over talc in the prepared composites.

关键词： filler Particle Size Polypropylene Snail Shell powder Composite

Thermal and Physicochemical Characterization of Fibers from Coffee Hulls as filler for Linear Low Density Polyethylene (LLDPE)

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Advances in Materials Physics and Chemistry 2021年第10期11卷 155-166页

作者： Ahmat Tom Abel Tame Paul Nestor Djomou Djonga Bakary Tigana Djonse Justin Eugenie Géraldine Nga Abena Department of Energy Engineering University Institute of Technology University of Ngaoundere Ngaoundere Cameroon Department of Chemistry Faculty of Science University of Yaoundé I Yaoundé Cameroon Department of Textile and Leather Engineering National Advanced School of Engineering of Maroua Maroua Cameroon Department of Chemistry Faculty of Science University of Maroua Maroua Cameroon Department of Physics Faculty of Science University of Yaoundé I Yaoundé Cameroon

This work presents the thermal, physical and chemical characterization of Coffee canephora, from littoral region of Cameroon, for their use as reinforcement for polymeric materials. The infrared of coffee hulls shows the presence of a large peak intensity at 3299 cm-1 that can be attributed to O-H stretching group of alcohol (cellulose content in coffee pulp). The intensity 2926 cm-1 can be attributed to C-H stretching group of alkanes or the vibration of methoxy group of lignin. Thermo gravimetric analysis shows that around 440°C, the biomass has been completely consumed;the temperature profiles show a peak at 86°C that could correspond to the loss of water as evaporation at a percentage of 8%;the peak at 321°C is accompanied by a water loss of 64.50%; this temperature is assimilated to the degradation of hemicelluloses;the temperature range from 321°C to 401°C is accompanied by a loss of mass of 22.80%, which would be due to the degradation of cellulose. SEM images of the surface of raw coffee hulls, coffee hulls treated with caustic soda respectively clearly reveal gaps between the fibers. The results showed that the incorporation of coffee hulls fiber in LLDPE matrix might result in composites with suitable property application for various industrial fields

关键词： Characterization Coffee Hulls filler LLDPE Physicochemical and Thermal

Activating a Protocol for Prevention, Management and Follow up of Dermal filler Injection Related Vascular Occlusion (A Clinical Audit)

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Modern Plastic Surgery 2020年第4期10卷 120-126页

作者： Ahmed Abdelmoez Alsayed Independent Researcher Al-Hokail Khobar Saudi Arabia

With the increased demand for dermal filler injections, more complications and adverse events are reported. Vascular occlusion is one of the most serious complications. The need urges to adopt a powerful protocol to manage such cases. The private practice I am working for has six branches in the middle east. I tried to investigate if there were any vascular occlusion incidences through the last three years. Four cases without sufficient details were found. A protocol was adopted from a scientific reference to deal with similar cases properly. A re-audit was done after six months to test the efficiency of the suggested protocol.

关键词： Dermal filler Vascular Occlusion Code: Pale

Sustainable Construction—High Performance Concrete Containing Limestone Dust as filler

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World Journal of Engineering and Technology 2017年第3期5卷 404-411页

作者： Tahir Kibriya Leena Tahir Senior Consulting Engineer Black & Veatch Toronto Canada (ex Faculty/Head of Civil Engineering Department NUST Risalpur Pakistan) MSc Structural Engineering City University London UK

Massive amounts of limestone waste are produced by the stone processing industry worldwide. Generally, it is believed that 60% to 70% of the stone is wasted in processing in the form of fragments, powder and slurry out of which around 30% is in the form of fine powder [1]. This waste has no beneficial usage and poses environmental hazards. Use of this waste product in the construction industry can largely reduce the amount of waste to be disposed off by the local municipalities in addition to reducing large burden on the environment. Some basic research on use of limestone dust as cement/ concrete filler?has?been carried out in the recent past but high strength/ high performance concretes have not been investigated yet [2] [3]. The concrete industry is among the largest consumer of raw materials worldwide and has been investigated for use of various types of waste materials like crushed brick, rice husk and straw ash as either aggregates for concrete or as partial cement substitutes. Use of limestone dust as filler material in concrete can consume a huge amount of this waste material which has to be disposed off otherwise, creating large burden on the environment. This experimental study aimed at evaluating the properties of high performance concretes made from Portland cement, natural aggregates and sand. Limestone dust was added by replacing sand in the percentages of 10% and 20%. Wide ranging investigations covering most aspects of mechanical behavior and permeability were carried out for various mixes for compressive strengths of 60?N/mm2, 80?N/mm2 and 100?N/mm2. Compressive strengths of concrete specimen with partial replacement of sand with 10% and 20% limestone dust as filler material for 60?N/mm2, 80N/mm2 and 100?N/mm2 were observed to be higher by about 4% to 12% than the control specimen. Flexural strengths were also observed to be higher by 12%?-?13%. Higher elastic moduli and reduced permeability were observed along with better sulphate and acid resistan

关键词： Limestone Dust filler Sustainable Construction Construction Waste High Strength Concrete Cement filler

Abdelmoez Hyaluronic Acid Dermal filler Scoring System

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Journal of Cosmetics, Dermatological Sciences and Applications 2019年第4期9卷 329-335页

作者： Ahmed Abdelmoez Alsayed Al-Hokail Khobar KSA

Introduction: Dermal fillers industry is ever-expanding. Tens, if not hundreds, of brands are available to purchase legally or illegally. I have attempted in this paper to develop a scoring system for Hyaluronic acid dermal fillers that makes an injector’s verdict objective, fair and unbiased, and injection experience safer. Theoretically speaking, the worst filler will have, at least, ᆠ score and the best will have a score of 34 points. Some scoring points do not exist in any filler, suggesting hints to improve all brands. Objectives: To build a Hyaluronic acid dermal filler scoring system that deals with what the injector can easily read, see or experience on their own without using sophisticated technologies or the need to understand or estimate the physics or the chemistry behind the filler. Using a scoring system that depends more on objective than subjective findings will be easy and unbiased to apply, more practical. The scoring system structure should be holistic rather than being only results centered and more focused on safety.

关键词： Hyaluronic Acid Dermal filler Scoring System

Effect of Geometry of filler Particles on the Effective Thermal Conductivity of Two-Phase Systems

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International Journal of Modern Nonlinear Theory and Application 2012年第2期1卷 40-46页

作者： Deepti Chauhan Nilima Singhvi Ramvir Singh Department of Physics Heat Transfer Laboratory University of Rajasthan Jaipur India

The present paper deals with the effect of geometry of filler particles on the effective thermal conductivity for polymer composites. In the earlier models, less emphasis has been given on the shape of filler particles. In this paper, expressions for effective thermal conductivity has been derived using the law of minimal thermal resistance and equal law of the specific equivalent thermal conductivity for three different shapes i.e. spherical, elliptical and hexagonal of filler particles respectively. Calculated values of effective thermal conductivity for various samples using the derived expressions then compared with experimental data available and other models developed in the literature. The results calculated are in good agreement with the earlier experimental data and the deviation, is least in our expressions showing the success of the model.

关键词： Effective Thermal Conductivity Polymer Composites Minimal Thermal Resistance Shape of filler

An Experimental Study of Self-Compacting Concrete Made with filler from Construction and Demolition Waste

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Open Journal of Civil Engineering 2020年第4期10卷 364-384页

作者： Mônica Batista Leite Marcela Crusoé Figueiredo Civil and Environmental Engineering Graduate Program Department of Technology State University of Feira de Santana Feira de Santana Brazil UNIFACS Feira de Santana Brazil

This study evaluated the influence of the Portland cement replacement by 0, 5%, 10%, 15% and 20% of Construction and Demolition Waste (CDW) filler contents in the production of self-compacting concrete (SCC). The SCC mixtures were evaluated on fresh state by slump flow, J-ring, resistance of segregation, specific gravity, and on hardened state by compressive and splitting tensile strength, specific gravity, air voids and absorption rate. The results indicated that all SCC produced with CDW filler met the limits established at any level of substitution without changes of the w/c ratio or superplasticizer content. It was possible to verify that the presence of CDW filler, in substitution of cement, by volume, improves the resistance to segregation and up to 5% of CDW filler decreases the loss of fluidity with time as compared to reference. It was found that all SCC mixtures, at 28 days, had the average compressive strength above 50 MPa, without showing significant loss with up to 20% of CDW filler. For splitting tensile strength, SCC recycled mixtures reached up to 92.5% of the SCC used as referenc

关键词： Self-Compacting Concrete Construction and Demolition Waste filler Mineral Admixtures Slump Flow

Production of filler Aggregate from Waste of Bivalves Molluscs Shells

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Journal of Civil Engineering and Architecture 2011年第4期5卷 363-367页

作者： Ulisses Targino Bezerra Fabio Luiz P. Almeida Lucineide Balbino Silva Normando Perazzo Barbosa TiberioA. Passos Danielle G. L. Cavalcante Federal Institute of Paraiba Av. 1°de Maio 720 Jaguaribe Joao Pessoa-PB Brazil Federal University of Paralba Castelo Branco S/N Joao Pessoa-PB Brazil

The work presents an experimental study held with shells of molluscs of the species Anomalocardia brasiliana and Tivela mactroides, commonly found in the Northeast coast of Brazil. A local community living from the collection of these animals was the motivation of the work. This community wishes to install an industry for processing these molluscs; however, as government agencies require making an appropriate allocation of discarded shells, the community needs an environmental project of final destination of waste. Thus, the expectation of the work was to obtain a material to be added to Portland cement to act as filler, and also obtain a limestone that can be used as ink, because the material is composed of 80% calcium carbonate. The shells were ground and passed the sieve 325 mesh （0.044 mm）. The material was characterized by X-ray diffraction and X-ray fluorescence. Mortars specimens were prepared with percentages： 0%, 5%, 10%, 15%, 20% and 30% replacement of Portland cement. Two conditions were analyzed： with shells in a raw and burned state. The obtained results confirm the filler material effect, which suggests its use as a partial replacement of cement. However, due to the short silicas＇s concentration, the pozzolanic effect was not observed.

关键词： Bivalves molluscs shells filler Portland cement mortar

Experimental Research about Denitrification by Box filler Enhancing MBR Process

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Meteorological and Environmental Research 2013年第1期4卷 57-60,66页

作者： Xuning Li Tingquan Pei Huan Liu Zhenye Zhao Liyong Mei Shenzhen-Hong Institution of Industry Education & Research Environmental Protection Engineering Technology Co.Ltd. Key Laboratory of Coastal and Atmospheric Research in Shenzhen

[Objective] The reseamh aimed to study removal effects of the organic matter and N by box filler enhancing MBR process. [ Method] By adding box filler into reaction pool of the MBR to treat domestic sewage, removal effects of the organic matter and N by box filler enhancing MBR process were studied. [ Result] COD means in effluent were respectively 26.8 and 24.7 mg/L without and with adding filler. Average removal rates of the NH3-N were respectively 98.44% and 96.37% with and without dosing filler, while average removal rates of the TN were 24.03% and 16.43%, respectively. COD and NH3-N concentrations in effluent were lower than Level-one A cdteda of Discharge Standard of the Pollutant for Municipal Wastewater Treatment Plant （ GB18918 -2002）. NO3^ -N was main existence form of the TN in effluent and occupied 98.06%, while NH3- N and NO2^--N only accounted for.1.22% and 0.72%. Further suggestion for denitrification study was as below. Firstly, the proportion of box filler on volume of the reaction cell should increase to 4% -5%. Secondly, single smaller filler with larger amount of internal fiber ought to be replaced. Thirdly, aeration amount needed to be decreased to right value, making that DO of the MBR reaction cell reduced to 1.5 -3.0 mg/L. [ Conclusion] The research provided theoretical basis for future engineering practice.

关键词： filler Membrane bioreactor Denitrification Removal effect China

Evaluation of filler Distribution in Particulate Reinforced Composites

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Journal of Materials Science and Chemical Engineering 2015年第7期3卷 108-112页

作者： Kurganova Yuliya Lopatina Yuliya Yijin Chen Department of Engineering Technology Bauman Moscow State Technical University Moscow Russia

Aluminum matrix particulate reinforced composites are of significant interest to industry, but it’s difficult to provide stable properties for this group of material. The mechanical properties of metal matrix composites are deeply influenced by the distribution of reinforcement particulates in the matrix. In this paper uniformity of SiC particles distribution in Al-based composites produced by stir casting and powder metallurgy technique is assessed. Analysis is carried out by means of classical and computer quantification metallographic image analysis methods. In addition, we suggest setting hardness distribution in cross section of samples as an indicator of reinforcement distribution uniformity in the matrix.

关键词： Particulate Reinforced Composites Metal Matrix Composites filler Distribution Quantification Metallographic Analysis Microhardness