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physical properties,Morphology and Petrological Characteristics of Pumices from the Central Indian Ocean Basin

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Acta Geologica Sinica(English Edition) 2011年第4期85卷 826-839页

作者： Niyati G.KALANGUTKAR Sridhar D.IYER Dandaydayudapani ILANGOVAN National Institute of Oceanography(Council of Scientific and Industrial Research) Dona PaulaGoa 403 004India

About 400 pumice clasts collected from the Central Indian Ocean Basin（CIOB）were studied for their morphology and were classified based on their shape and size.A majority of the samples range between1 cm and 36 cm and in the Zinggs shape diagram plot in the equant and oblate *** Corey Shape Factor for most of the samples is close to 0.7,which is common for volcaniclastic material. The physical properties such as density,specific gravity,void ratio,porosity,moisture content and degree of saturation,were determined for 30 pumice *** varies from 0.21 to 0.74 g/cm^3 specific gravity 1.84 to 3.27,void ratio 2.21 to 10.67,porosity 67%to 91%,moisture content during sinking 0.44 to 2.35 and degree of saturation varies from 26.5%to 86%.Binocular and electron microscopy studies reveal that 60%of the vesicles are elongated,30%are spherical and 10%are *** of the pumices exhibits vitrophyric texture with phenocrysts of feldspars and clinopyroxenes.X-ray diffractrogram and mineral analyses confirm plagioclase to be a major phase, while quartz and orthoclase are not *** is commonly present in the ferromanganese oxide coating present over some of the *** paper also delves into some details concerning the controversial origin of the pumices and glass shards in the CIOB.

关键词： pumice physical properties submarine Central Indian Ocean Basin

physical properties of Brachystegia Eurycoma seeds as affected by moisture content

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 84-93页

作者： Ndubisi A.Aviara Elizabeth B.Ibrahim Lovelyn N.Onuoha Department of Agricultural and Environmental Resources Engineering University of MaiduguriMaiduguriBorno StateNigeria

Some physical,frictional and thermal properties of Brachystegia eurycoma seed were studied at different moisture contents in order to explore the possibility of mechanizing the handling and processing *** showed that the seed could be considered an oval disc in *** the moisture range of 2.79%to 27.13%(d.b.),the major,intermediate and minor axial dimensions increased with increase in moisture content from 2.29 mm to 2.45 mm,1.65 mm to 1.91 mm and 0.34 mm to 0.52 mm,*** the above moisture range,one thousand seed weight,particle density,porosity,roundness,sphericity,surface area and angle of repose increased linearly from 0.901 kg to 1.252 kg,2270 kg/m^(3) to 2520 kg/m^(3),11.23%to 15.46%,35%to 47%,67%to 82%,7.67 cm^(2) to 8.48 cm^(2) and 16.8°to 29.2°respectively,while bulk density decreased from 745.4 kg/m^(3) to 613.6 kg/m^(3).Static coefficient of friction on different structural surfaces increased linearly with moisture content and had the highest values on galvanized steel sheet(0.445-0.639),and the lowest values on fiber glass(0.287-0.404).Kinetic coefficient of friction increased linearly with moisture content on different structural surfaces except on galvanized steel sheet where it decreased linearly with increase in moisture content in the above moisture *** had the highest values on hessian bag material(0.266-0.389),and the lowest values on plywood with wood grains perpendicular to the direction of movement(0.204-0.271).Specific heat ranged from 1474 to 5992.7 J/kgK,and increased with increase in moisture content and *** equations were used to express the relationships existing between the seed properties and moisture content.

关键词： Brachystegia eurycoma physical properties seed processing frictional properties specific heat moisture content

Structures and physical properties of R_2TX_3 compounds

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Chinese Physics B 2013年第5期22卷 392-401页

作者：潘志艳曹崇德白晓军宋瑞波郑建邦段利兵 Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education

Rare-earth compounds have been an attractive subject based on the unique electronic structures of the rare-earth elements. Novel ternary intermetallic compounds R2TX3 （R = rare-earth element or U, T = transition-metal element, X = Si, Ge, Ga, In） are a significant branch of this research field due to their complex and intriguing physical properties, such as magnetic order at low temperature, spin-glass behavior, Kondo effect, heavy fermion behavior, and so on. The unique physical properties of R2TX3 compounds are related to distinctive electronic structures, crystal structures, micro- interaction, and external environment. Most R2TX3 compounds crystallize in A1B2-type or derived A1B2-type structures and exhibit many similar properties. This paper gives a concise review of the structures and physical properties of these compounds. Spin glass, magnetic susceptibility, resistivity, and specific heat of R2 TX3 compounds are discussed.

关键词： R2TX3 compounds structure physical properties

Microstructure and physical properties of steel-ladle purging plug refractory materials

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 186-193页

作者： Bin Long Gui-ying Xu Buhr Andreas School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Almatis Qingdao Co. Ltd. Qingdao 266071 China Almatis GmbH Frankfurt 60528 Germany

Three different castables were prepared as steel-ladle purging-plug refractory materials： corundum-based low-cement castable （C-LCC）, corundum-spinel-based low-cement castable （C-S-LCC）, and no-cement corundum-spinel castable （C-S-NCC）（hydratable alu- mina p-A1203 bonded）. The properties of these castables were characterized with regard to water demand/flow ability, cold crushing strength （CCS）, cold modulus of rupture （CMoR）, permanent linear change （PLC）, apparent porosity, and hot modulus of rupture （HMoR）. The re- sults show the CCS/CMoR and HMoR of C-LCC and C-S-LCC are greater than those of the castable C-S-NCC. According to the micro- structure analysis, the sintering effect and the bonding type of the matrix material differ among the three castables. The calcium hexaluminate （CA6） phase in the matrix of C-LCC enhances the cold and hot mechanical strengths. In the case of C-S-LCC, the CA6 and 2CaO·2MgO·14A12O3（C2MEA14） ternary phases generated from the matrix can greatly increase the cold and hot mechanical strengths. In the case of the no-cement castable, sintering becomes difficult, resulting in a lower mechanical strength.

关键词： refractory materials purging plugs castable physical properties microstructure

Effect of grinding on chemical and physical properties of rice husk ash

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 242-247页

作者： Sumrerng Rukzon Prinya Chindaprasirt Rattana Mahachai Department of Civil Engineering Rajamangala University of Technology Phra NakhonBangkok 10300Thailand Department of Civil Engineering Faculty of EngineeringKhon Kaen University40002Thailand Department of Chemistry Faculty of ScienceKhon Kaen University40002Thailand

The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used for the study. Ordinary Portland cement （OPC） was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio （W/B） of the mortar was maintained at 110%±5% with flow table test. Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined. The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small. The use of RHA3 produces the mortars with good strength and low porosity. The strength of the mortar improves with partial replacement of RHA3 in comparison with normal coarse rice husk ash. The use of RHA3 results in a strong and dense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.

关键词： fineness grinding mortar physical properties rice husk ash

Effect of Fe_(2)O_(3)on the Structure,physical properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 954-961页

作者：张峰 XIONG Dehua 谢俊张继红 HAN Jianjun CHEN Dequan WEN Zhongquan FAN Zhenhua CHEN Lina SUN Tengfei State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Hepu Research Center for Silicate Materials Industry Technology Beihai 536100China Hainan Institute of Wuhan University of Technology Sanya 430079China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China Chongqing Polycomp Inter-national Corporation Chongqing 400400China

The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching *** glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,X-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope *** change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass *** glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content *** is almost no thermal expansion coefficient change from different Fe_(2)O_(3)*** glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)*** calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional *** of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals.

关键词： calcium aluminosilicate glass network structure physical properties crystallization

Lanthanide amino acid Schiff base complexes:synthesis,spectroscopic characterization,physical properties and in vitro antimicrobial studies

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Journal of Rare Earths 2013年第7期31卷 715-721页

作者： Samir Alghool M.Sh.Zoromba Hanan F.Abd El-Halim Department of Chemistry Faculty of SciencePort Said UniversityPort Said 42521Egypt Department of Chemistry Faculty of PharmacyMisr International UniversityIsmailia RoadKm 28 CairoEgypt

Complexes of La （III）, Nd（III）, Gd（III）, Sm（III）, and Ce（IV） were synthesized with Schiff base [（3,5-di-tert-butyl-2-hy- droxybenzyl） amino] acetic acid （H3L）. The ligand and its complexes were synthesized and characterized based on the following analysis： elemental analyses, FAB-mass, molar conductance measurements, magnetic measurement, UV-visible, IR, and NMR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to metal ion through ONO donor sequence. Thermal degradation studies of the ligand and its complexes showed that the previous lanthanide complexes were more thermally stable than the ligand itself. The Schiff base and its complexes were screened for their antibacterial （Escherichia coli, Staphylococcus aureus） and antifungal （Aspergillus flavus and Candida Albicans）.

关键词： lanthanide Schiffbase complexes physical properties biological activity rare earths

Mechanical and physical properties of Pineapple Leaf and Sun Hemp Fibre Reinforced Hybrid Natural Composite Fabricated by Compression Moulding Method

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Journal of Bionic Engineering 2022年第1期19卷 257-267页

作者： A.Arun Premnath Centre for Composite Science and Tribology Sri Chandrasekharendra Saraswathi Viswa MahavidyalayaKanchipuramTamilnadu631561India

The implementation of natural fibres in polymer composites will result in biodegradable,low cost,recyclable materials for automobile and structural *** the process of making natural fibre composites viable in the global market,it is essential to understand its mechanical and physical *** the present investigation,mechanical and physical properties of pineapple Leaf(PALF)and Sun Hemp(SH)Fibre reinforced with epoxy matrix was studied in terms of weight(wt)%of fibre loading and chemical *** composites were fabricated by compression moulding technique with PALF fibre content varying from 10,15 and 20%of weight *** PALF and SHF were treated with NaOH solution for 1 h at room *** various mechanical properties such as tensile,compression,flexural and impact strength were measured as per ASTM *** density and water absorption were also measured to study the physical properties of the fabricated *** treated composites exhibit a rough surface because of the removal of the cellulose layer which results in better adhesion between the matrix/fibre interface than untreated *** NaOH treated fibres composites outperformed untreated fibre composites in terms of mechanical and physical properties except for impact *** morphological studies of the worn surfaces are examined using Scanning Electron Microscope(SEM).

关键词： Pineapple leaf fibre Compression moulding Mechanical properties physical properties Morphological studies

Impact of rock type on the pore structures and physical properties within a tight sandstone reservoir in the Ordos Basin, NW China

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Petroleum Science 2020年第4期17卷 896-911页

作者： Xiang-Dong Yin Shu Jiang Shi-Jia Chen Peng Wu Wei Gao Ji-Xian Gao Xian Shi State Key Laboratory of Oil and Gas Reservoir Geology and Exploration Southwest Petroleum UniversityChengdu610500SichuanChina Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education and School of Earth Resources China University of GeosciencesWuhan430074HubeiChina Energy and Geoscience Institute University of UtahSalt Lake CityUT84108USA Unconventional Oil and Gas Branch CNOOC Ltd.Beijing100011China Oil and Gas Technology Research Institute Changqing Qilfield CompanyXi’an City710021ShaanxiChina School of Petroleum Engineering China University of Petroleum(Huadong)Qingdao266000ShandongChina

The pore-throat systems and physical properties of tight sandstone reservoirs are complex,and deposition is thought to be a fundamental control for *** this study,the impacts of the full ranges of rock types(from pebbly coarse sandstone to fine sandstone) on the pore structures and physical properties of the Permian tight sandstone reservoir in the eastern Ordos Basin were investigated comprehensively through a series of experiments including conventional physical testing,thin-section analysis,scanning electron microscopy,nuclear magnetic resonance analysis and high-pressure mercury injection *** results showed that the coarser-grained sandstones tend to have higher feldspar content and lower percentage of cements,leading to strong dissolution,weak cementation and improved porosity and *** medium sandstone has the highest level of quartz and the lowest average content of feldspar,resulting in strong heterogeneity of physical *** those medium sandstone reservoirs with relatively high content of feldspars have better physical ***,the coarser-grained sandstones contain relatively large dissolution pores(nearly 200 μm),whereas the finer-grained sandstones have more intercrystalline pores with a relatively more homogeneous pore *** pebbly coarse sandstone and coarse sandstone reservoirs are favorable targets with best physical properties.

关键词： Pore size distribution Pore types physical properties Tight sandstone Ordos Basin