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石灰窑分石电子控制器
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作者 杨武峰 《纯碱工业》 CAS 2000年第1期57-58,共2页
关键词 石灰窑 分石器 电子控制
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中国的石叶技术 被引量:12
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作者 加藤真二 《人类学学报》 CSCD 北大核心 2006年第4期343-351,共9页
在旧石器时代晚期,中国北方的地域性石器工业之中也有石叶技术。最典型的实例是山西峙峪的,其特征是:1)制作技术简单;2)生产小型—中型石叶;3)石料的材料较好;4)在技术体系当中的作用较低。根据这些特征的有无,可以将中国北部的石叶技... 在旧石器时代晚期,中国北方的地域性石器工业之中也有石叶技术。最典型的实例是山西峙峪的,其特征是:1)制作技术简单;2)生产小型—中型石叶;3)石料的材料较好;4)在技术体系当中的作用较低。根据这些特征的有无,可以将中国北部的石叶技术划分为许家窑以前的阶段、许家窑阶段(10—3.5万年前)、峙峪—小南海阶段(3.5—1.7万年前)这样3个阶段。本文主张这3个阶段分别相当于欧亚大陆西部的旧石器时代早、中、晚期。 展开更多
关键词 石叶技术 中国北方 峙峪 小南海 许家窑 石器
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Spatial Distribution of Archaeological Sites in Lakeshore of Chaohu Lake in China Based on GIS 被引量:1
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作者 GAO Chao WANG Xinyuan +1 位作者 JIANG Tong JIN Gaojie 《Chinese Geographical Science》 SCIE CSCD 2009年第4期333-340,共8页
There are about 19 Neolithic Age sites and 120 Shang-Zhou dynasties sites in the western lakeshore of Chaohu Lake,Anhui Province,China.Based on sites data,topographic data,drainage maps,administrative maps and SPOT5 r... There are about 19 Neolithic Age sites and 120 Shang-Zhou dynasties sites in the western lakeshore of Chaohu Lake,Anhui Province,China.Based on sites data,topographic data,drainage maps,administrative maps and SPOT5 remote sensing data,spatial analysis methods were introduced into the archaeology of Chaohu Lake Basin with Geographic Information System(GIS).The spatial analysis methods include:1) Point Density Analysis with density model to acquire the shift of the sites;2) Distance Analysis to reveal the spatial structure of the sites;3) 3D Analysis based on Digital Elevation Model to get micro-geomorphologic features of the sites;and 4) Buffer Analysis to discover the relationship between the sites and rivers.The results indicate that the archaeological sites spread from the western lakeshore of Chaohu Lake gradually to the northwest,later to the south,and then symmetrically spread.Controlled by productive forces and other factors,ancient people preferred to reside in those places near water,or in plain and fertile land,which resulted in linear and decentralized distribution of the sites,and presented such disciplines as river valley directivity,terrace directivity and soil directivity.This paper indicates that the distribution of archaeological sites was influenced earlier by natural elements and later by human elements in the study period.The research is important for the integration of GIS and archaeology. 展开更多
关键词 archaeological site Geographic Information System spatial analysis Chaohu Lake
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Novel Portable Oil Ingredient Instrument with Optical Fiber Link
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作者 WANGShu-tao SHIJin-shan 《Semiconductor Photonics and Technology》 CAS 2001年第2期109-113,119,共6页
The operation principle of a novel portable oil ingredient instrument is introduced. Using the theory of fluorescence measurement, this instrument can carry out fast and consecutive in-situ detection of oil ingredient... The operation principle of a novel portable oil ingredient instrument is introduced. Using the theory of fluorescence measurement, this instrument can carry out fast and consecutive in-situ detection of oil ingredient in sea water, confirming fast and correctly the situation of oil contamination such as the concentration and the area, etc. The lowest detectable concentration for the instrument is 1×10 -8 g/ml with the precision of less than 3 %. The results of experiment and practice show that this system has well water-sealed characteristic and repeatability. 展开更多
关键词 Fluorescence measurement Excitation spectrum Fluorescence spectrum Optical fiber
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Commissioning of Commercial Scale Pressure Filter Test Facility of PTA Unit at Yangzi Petrochemical Co.
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《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2008年第2期59-59,共1页
The Yangzi Petrochemical Company has successfully imple-mented the test commissioning of a 45 t/h pressure filter (base on dry feed material) installed in the PTA unit with its pressure filter technique commanding a l... The Yangzi Petrochemical Company has successfully imple-mented the test commissioning of a 45 t/h pressure filter (base on dry feed material) installed in the PTA unit with its pressure filter technique commanding a leading 展开更多
关键词 试车 过滤器 石油化学品 回收 净化
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A Novel Multi-Tube Photoreactor with UV Light and Immobilized TiO_2 Thin Film for Water Treatment 被引量:7
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作者 谢一兵 沈迅伟 袁春伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第1期27-32,共6页
A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-c... A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-catalyst. Total active area of TiO2 thin film is 0.3916m2. The ratio of surface area to volume achieves 20.8m-1. Photocatalytic experiment of phenol red demonstrates that the apparent reaction rate constant (k) is 0.074 65 h-1 and 0.16502h-1 for reaction system with and without micro-bubbles mixing. The corresponding apparent quantum efficiency (a) is 8.1771 X 10-7g.J-1 and 4.9036 x 10-7g-J-1, respectively. COD value of reactant could decrease to 17mg.L-1 and high performance liquid chromatography (HPLC) only shows two absorption peaks in 24 h pho-tocatalytic process time, so this photoreactor has good photomineralization effect. Experimental results reveal that photocatalytic destruction of organics is possible by using the multi-tube photoreactor. 展开更多
关键词 PHOTOREACTOR PHOTOCATALYST TiO2 thin film apparent quantum efficiency
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Studying distribution of rare earth elements by classifiers,Se-Chahun iron ore,Central Iran
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作者 Mohammadali Sarparandeh Ardeshir Hezarkhani 《Acta Geochimica》 EI CAS CSCD 2017年第2期232-239,共8页
The increased production and price of rare earth elements(REEs) are indicative of their importance and of growing global attention. More accurate and practical exploration procedures are needed for REEs, and for other... The increased production and price of rare earth elements(REEs) are indicative of their importance and of growing global attention. More accurate and practical exploration procedures are needed for REEs, and for other geochemical resources. One such procedure is a multivariate approach. In this study, five classifiers, including multilayer perceptron(MLP), Bayesian, k-Nearest Neighbors(KNN), Parzen, and support vector machine(SVM),were applied in supervised pattern classification of bulk geochemical samples based on REEs, P, and Fe in the Kiruna type magnetite-apatite deposit of Se-Chahun,Central Iran. This deposit is composed of four rock types:(1) High anomaly(phosphorus iron ore),(2) Low anomaly(metasomatized tuff),(3) Low anomaly(iron ore), and(4)Background(iron ore and others). The proposed methods help to predict the proper classes for new samples from the study area without the need for costly and time-consuming additional studies. In addition, this paper provides a performance comparison of the five models. Results show that all five classifiers have appropriate and acceptable performance. Therefore, pattern classification can be used for evaluation of REE distribution. However, MLP and KNN classifiers show the same results and have the highest CCRs in comparison to Bayesian, Parzen, and SVM classifiers. MLP is more generalizable than KNN and seems to be an applicable approach for classification and predictionof the classes. We hope the predictability of the proposed methods will encourage geochemists to expand the use of numerical models in future work. 展开更多
关键词 Geochemical exploration of REEs Supervised pattern classification Geochemistry of Se-Chahun ~Central Iran
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Full-Scale Measurement and Numerical Analysis of Liquefied Petroleum Gas Water Heaters with Ventilation Factors in Balcony
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作者 Chen-Wei Chiu Chiun-Hsun Chen +1 位作者 Chun-Wan Chen Yueh-Jen Chen 《Journal of Civil Engineering and Architecture》 2015年第11期1341-1353,共13页
This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtig... This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space. 展开更多
关键词 Water heater carbon monoxide FDS POISON LPG (liquefied petroleum gas).
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Pressure Oxidative Leaching of Complex Sulphide Concentrate
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作者 Vladislav Lj. Matkovie Miroslav D. Sokic Branislav R. Markovic 《Journal of Chemistry and Chemical Engineering》 2011年第9期828-831,共4页
The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was perfor... The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was performed using the sulphur acid solution with the oxygen addition for the separation of the targeted metals from the polymetallic concentrate. In this process influences of various parameters were discussed and then correlated to the leached metals, zinc, copper and iron. Zinc, copper and iron were dissolved in a solution, while lead remained as insoluble in the leach residue. The best leaching results were determined under the temperature of 210 ℃ during the 240 min. Obtained leaching degrees were 98% zinc, 95% copper and 96% iron. 展开更多
关键词 Complex concentrate presure leaching sulphuric acid oxygen.
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四川西昌市横栏山新石器时代遗址调查 被引量:13
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作者 张正宁 《考古》 CSSCI 北大核心 1998年第2期5-9,共5页
1987年,四川西昌市文物管理所进行文物普查时,在西昌市大兴乡横栏山半山坡上发现一处新石器时代遗址,简称横栏山遗址。这是西昌境内继1974年发现礼州新石器时代遗址后,又发现的一处新石器时代的重要遗址。一、地理环境及地层情况横栏山... 1987年,四川西昌市文物管理所进行文物普查时,在西昌市大兴乡横栏山半山坡上发现一处新石器时代遗址,简称横栏山遗址。这是西昌境内继1974年发现礼州新石器时代遗址后,又发现的一处新石器时代的重要遗址。一、地理环境及地层情况横栏山遗址位于西昌城东南15公里的大兴乡横栏山的半山坡上。 展开更多
关键词 石器时代遗址 西昌市 横栏 礼州 四川 地理环境 分石器 器身 陶器 文化层
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湖南益阳鹿角山发现新石器时代遗址 被引量:1
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作者 周世荣 《考古》 1965年第10期536-537,共2页
1964年10月,益阳市桃花命公社红砖厂在鹿角山取土烧砖时发现了石器多件。该厂工人吴静平同志当即写信报告湖南省博物馆,经派人调查,发现为新石器时代遗物。兹将调查及试掘概况简单报导于后: 庞角山位于益阳市南郊约2.5公里,它高出水田... 1964年10月,益阳市桃花命公社红砖厂在鹿角山取土烧砖时发现了石器多件。该厂工人吴静平同志当即写信报告湖南省博物馆,经派人调查,发现为新石器时代遗物。兹将调查及试掘概况简单报导于后: 庞角山位于益阳市南郊约2.5公里,它高出水田约20米。东邻三里桥小镇,西为桃花命,南迈黑山庙,北滨(氵资)水而与益阳市遥遥相望。遗址位于山肩的西南面,面积约60平方米,现残存文化堆积断续的分为六处,我们选择正中的一处试掘了一个1×2. 展开更多
关键词 石器时代遗址 益阳市 鹿角 文化堆积 分石器 发现 桃花 砂质板岩 湖南益阳 文化层
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Graphene-based thermal modulators 被引量:3
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作者 Xiangjun Liu Gang Zhang Yong-Wei Zhang 《Nano Research》 SCIE EI CAS CSCD 2015年第8期2755-2762,共8页
The quest for materials and devices that are capable of controlling heat flux continues to fuel research on thermal controlling devices. In this letter, using molecular dynamics simulations, we demonstrate that a part... The quest for materials and devices that are capable of controlling heat flux continues to fuel research on thermal controlling devices. In this letter, using molecular dynamics simulations, we demonstrate that a partially clamped singlelayer graphene can serve as a thermal modulator. The mismatch in phonon dispersion between the unclamped and clamped graphene sections results in phonon interface scattering, and the strength of interface scattering is tunable by controlling the clamp-graphene distance via applying the external pressure. Owing to the ultra-thin structure of graphene and its highly sensitive phonon dispersion to external physical interaction, the modulation efficiency--which is defined as the ratio of the highest to lowest heat flux-can reach as high as 150% at a moderate pressure of 50 GPa. This modulation efficiency can be further enhanced by arranging a number of clamps in series along the direction of the heat flux. 展开更多
关键词 GRAPHENE thermal modulator molecular dynamics thermal conductivity phonon dispersion
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