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Effect of Organic Waste on Crystal Structure and Mechanical Properties of Concrete

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Journal of Minerals and Materials Characterization and Engineering 2015年第5期3卷 427-434页

作者： Samuel Oloruntoba Olugbenga Olusunle Theresa Chikwuo Ezenwafor Bidemi Sikirat Jiddah-Kazeem Akeem Kareem Ojo jeremiah Akinribide Adekunle Taofeek Oyelami Engineering Materials Development Institute Akure Nigeria

The influence of organic waste as an additive to concrete formulation has been studied by replacing up to 10% of cement ratio with locally sourced organic additive. The reference cement used was Portland cement;three different organic wastes were used in the mixture: periwinkle shell, extracted silica from corn hob ash and coconut shell ash. Uniform distribution of the additive was ensured by thorough mixing prior to water addition. Casting and curing of the concrete were done in line with established standard. The compressive strength test was carried out using the Instron universal testing machine and the oxides of elemental composition of the cement and the additives were determined using EDXRF Spectrometer (EDX 3600B) while the crystallography studies were carried out using EMMA) X-ray diffractometer . The result obtained indicated that there was a significant difference between the value of density, packing efficiency and compressive strength of each reinforced concrete with that of the reference cement which was attributable to the presence of additives. The cement formulation with silica as admixture was found to have the highest compressive strength of 217.94 MPa, while the reference cement had the lowest compressive strength of 81.45 MPa. This study has established that locally sourced organic additives (emerging additives), influence the mechanical properties of concretes.

关键词： High Strength Concrete (HSC) Organic Waste Compressive Strength Elemental Characterization

Evaluation of Effects of Synthetic Compound and Mineral Admixture on Crystal Structure of Concrete

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Journal of Minerals and Materials Characterization and Engineering 2015年第3期3卷 134-141页

The effects of mineral admixture on the internal morphology of concrete were studied and evaluated in this work. Portland cement with five different additives was used in the complex admixture. These includes: extracted silica from corn hob ash, synthetic calcium carbonate, synthetic calcium hydrogen carbonate, white and dark kaolin, each replacing 10% of cement in the concrete formulation. The additives and the pure cements were subjected to intensive mixing to ensure homogeneity prior to water addition, after which each undergoes casting and curing. Elemental characterizations of the additives indicated the presence of some elemental oxides and crystallography studies were carried out on the pure and reinforced concrete. The obtained result indicated crystallographic adjustments of the indigenous concrete which will definitely contribute to modifying its mechanical properties.

关键词： Synthetic Carbonates Crystallography Elemental Characterization

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如何更有效进行绩效考核

新理财（公司理财） 2020年第9期 61-63页

作者： jeremiah Bentley Margaret Shackell Pamela Trafford 不详

将叙述式报告纳入员工KPI考核,将有助于避免只采用数字指标所带来的经营扭曲,并能更加清晰地展示绩效情况。关键绩效指标(KPI)通过向管理人员提供绩效评价、资源配置、战略指引所需的数据,促进组织绩效持续改善。

关键词：绩效考核资源配置绩效评价绩效情况管理人员数字指标绩效持续

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开展林权制度改革政策环境影响评价促进林业绿色发展

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环境与可持续发展 2012年第2期37卷 5-10页

作者：张颖杨桂红陆霁 Haron jeremiah 北京林业大学经济管理学院北京100083

我国历经6年的林权制度改革作为促进林业发展的根本措施,正在不断深化并已经取得很大成就。但同时也应看到其对生态环境具有一定影响(正面和负面影响)。如果国家在实施林业制度改革之前或实施初期对其可能带来的生态环境影响进行预先的... 详细信息

我国历经6年的林权制度改革作为促进林业发展的根本措施,正在不断深化并已经取得很大成就。但同时也应看到其对生态环境具有一定影响(正面和负面影响)。如果国家在实施林业制度改革之前或实施初期对其可能带来的生态环境影响进行预先的评估,有利于最大程度地减少其负面影响和扩大其正面影响,将有助于决策者做出科学决策。因此开展林权改革环境影响理论与实践研究成为当务之急,是进一步开展好林权制度改革后续的配套政策措施研究的重要内容,是保障林权改革相关政策顺利实施的重要保障。为此建议:第一,国家相关部门要高度关注林权制度改革过程中对生态环境的影响;第二,应尽快深入开展林权改革环境影响评价理论与实践研究;第三,把林权改革作为重点领域开展政策环境影响评价试点,为在规划环评基础上进一步实施政策环评制度提供技术支撑,为修改《环评法》和政策环评作好技术储备,为促进林业绿色发展保驾护航。

关键词：林权制度改革环境影响政策环境影响评价配套制度措施

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暗物质研究的曙光

世界科学 2003年第9期 4-7页

作者： jeremiah P.Ostrikerr ,Paul Steinhardt ,谢懿

几十年前,暗物质刚被提出来时仅仅是理论的产物,但是现在我们知道暗物质已经成为了宇宙的重要组成部分。暗物质的总质量是普通物质的6倍,在宇宙能量密度中占了1/4,同时更重要的是,暗物质主导了宇宙结构的形成。暗物质的本质现在还是个谜... 详细信息

几十年前,暗物质刚被提出来时仅仅是理论的产物,但是现在我们知道暗物质已经成为了宇宙的重要组成部分。暗物质的总质量是普通物质的6倍,在宇宙能量密度中占了1/4,同时更重要的是,暗物质主导了宇宙结构的形成。暗物质的本质现在还是个谜,但是如果假设它是一种弱相互作用亚原子粒子的话,那么由此形成的宇宙大尺度结构与观测相一致。不过,最近对星系以及亚星系结构的分析显示,这一假

关键词：暗物质普通物质无碰撞团块暗物质晕伴随粒子超对称星系盘星系结构尺度结构宇宙年龄物质模型候选者太阳质量中心密度面密度 SADM 理论预言曙光

Design and Development of Grip for Circular Test Piece Inuniversal Tensile Testing Machine

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Journal of Minerals and Materials Characterization and Engineering 2013年第6期1卷 331-335页

作者： Ojo jeremiah Akinribide Adetunji Kolawole Ogunkoya Itopa Monday Momoh Olasupo Daniel Ogundare Ba’aku Emmanuel AttahDaniel Samuel Olugbenga Oloruntoba Olusunle Engineering Materials Development Institute Akure Nigeria

The design and development of jaw grip for circular tensile test samples in a universal mechanical tester were undertaken in this work. In developing economies, the cost of acquiring laboratory testing equipment and accessories is huge, thereby depriving most of the supposedly advanced laboratories of most of this necessary research equipment. Where the equipment is available, they are either non-functional due to inadequate maintenance know-how or non-availability of necessary accessories. The developed grip in this work is part of an effort at providing accessories as their need arises. Advanced design and manufacturing tools were deployed to develop the jaw grip by using austenitic stainless steel. The developed jaw grip was used on the test equipment to conduct tensile tests on steel samples and the results were found to conform to international standard. Consequently, replacement of worn-out accessories has been carried out in resent time, which eventually saves idle time of equipment or otherwise importation for replacement.

关键词： Mechanical Testing Tensile Test Jaw Grip

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CONTAGION

The World of Chinese 2020年第3期 26-38页

作者： jeremiah JENNE J.J. HATTY LIU SAM DAVIES 不详

In 2010,archeologists came across the grisly sight of over 100 skeletons stuffed into small rooms in a Neolithic ruin in Inner *** have since theorized that these were victims of some prehistoric plague,who were hasti... 详细信息

关键词：肺鼠疫公共卫生体系流行病天花清朝末年明末清初

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Global spatio-temporally harmonised datasets for producing high-resolution gridded population distribution datasets

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Big Earth Data 2019年第2期3卷 108-139页

作者： Christopher T.Lloyd Heather Chamberlain David Kerr Greg Yetman Linda Pistolesi Forrest R.Stevens Andrea E.Gaughan jeremiah J.Nieves Graeme Hornby Kytt MacManus Parmanand Sinha Maksym Bondarenko Alessandro Sorichetta Andrew J.Tatem WorldPop School of Geography and Environmental ScienceUniversity of SouthamptonSouthamptonUK Flowminder Foundation StockholmSweden Center for International Earth Science Information Network(CIESIN) Columbia UniversityPalisadesNYUSA Department of Geography and Geosciences University of LouisvilleLouisvilleKYUSA GeoData University of SouthamptonSouthamptonUK

Multi-temporal,globally consistent,high-resolution human population datasets provide consistent and comparable population distributions in support of mapping sub-national heterogeneities in health,wealth,and resource access,and monitoring change in these over *** production of more reliable and spatially detailed population datasets is increasingly necessary due to the importance of improving metrics at sub-national and multitemporal *** is in support of measurement and monitoring of UN Sustainable Development Goals and related *** response to these agendas,a method has been developed to assemble and harmonise a unique,open access,archive of geospatial *** are provided as global,annual time series,where pertinent at the timescale of population analyses and where data is available,for use in the construction of population distribution *** archive includes sub-national census-based population estimates,matched to a geospatial layer denoting administrative unit boundaries,and a number of co-registered gridded geospatial factors that correlate strongly with population presence and ***,we describe these harmonised datasets and their limitations,along with the production ***,we demonstrate applications of the archive by producing multi-temporal gridded population outputs for Africa and using these to derive health and development *** geospatial archive is available at https://***/10.5258/SOTON/WP00650.

关键词： Human population subnational global spatial dataset multi-temporal

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WHEN STARS ATTACK

The World of Chinese 2020年第5期 36-36页

作者： jeremiah JENNE

An ancient disaster from the sky baffles historians Every day,an estimated 25 million pieces of space debris enter our planet’s ***,most of these are small,even microscopic,and burn up before they reach the *** calculate,though,that each day an extraterrestrial object at least 40 centimeters in diameter might make it to the Earth’s surface.

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