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城市桥梁美学在设计中的应用——以南平大桥为例
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作者 何训华 《中国科技期刊数据库 工业A》 2023年第7期73-76,共4页
现代桥梁已不纯粹满足以功能为目的,已逐渐将桥梁美和环境美融合,在满足功能的前题下对景观生态、景观文化、地域文化等进行美学融合,实现美学和历史以及文化之间的接驳,把桥梁打造成城市文化形象的窗口。本文以南平大桥景观设计为例,... 现代桥梁已不纯粹满足以功能为目的,已逐渐将桥梁美和环境美融合,在满足功能的前题下对景观生态、景观文化、地域文化等进行美学融合,实现美学和历史以及文化之间的接驳,把桥梁打造成城市文化形象的窗口。本文以南平大桥景观设计为例,详细描述其在新的桥梁美学设计思路下如何进行历史与文化的融合以及美学元素重构,为今后类似工程设计拓宽了思路。 展开更多
关键词 桥梁美学 形式美、技艺 仿生理念 历史文化元素融合
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A High Voltage BCD Process Using Thin Epitaxial Technology 被引量:1
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作者 乔明 肖志强 +7 位作者 方健 郑欣 周贤达 徐静 何忠波 段明伟 张波 李肇基 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1742-1747,共6页
A high voltage BCD process using thin epitaxial technology is developed for high voltage applications. Compared to conventional thick expitaxial technology, the thickness of the n-type epitaxial layer is reduced to 9... A high voltage BCD process using thin epitaxial technology is developed for high voltage applications. Compared to conventional thick expitaxial technology, the thickness of the n-type epitaxial layer is reduced to 9μm,and the diffusion processing time needed for forming junction isolation diffusions is substantially reduced. The isolation diffusions have a smaller lateral extent and occupy less chip area. High voltage double RESURF LD- MOS with a breakdown voltage of up to 900V,as well as low voltage CMOS and BJT,are achieved using this high voltage BCD compatible process. An experimental high voltage half bridge gate drive IC using a coupled level shift structure is also successfully implemented, and the high side floating offset voltage in the half bridge drive IC is 880V. The major features of this process for high voltage applications are also clearly demonstrated. 展开更多
关键词 BCD process thin epitaxial technology double RESURF LDMOS
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Study on Processing Technology of Health Beverage Made from Artemisia Selengensis Turoz and Green Tea 被引量:1
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作者 吴存兵 吴君艳 +3 位作者 田林双 窦勇 李昱萱 彭芳琦 《Agricultural Science & Technology》 CAS 2014年第6期990-993,共4页
This study took Artemisia selengensis Turoz and green tea as primary materials and sugar, lemon acid potassium as supplementary materials to make compound health beverage.The main influence factors to the quality of t... This study took Artemisia selengensis Turoz and green tea as primary materials and sugar, lemon acid potassium as supplementary materials to make compound health beverage.The main influence factors to the quality of the compound beverage were investigated,such as addition amounts ofArtemisia selengensis juice, green tea juice,sugar and lemon acid.By orthogonal test ,the best formula of the compound health beverage is Artemisia selengensis juice 10 ml, green tea juice 200 ml, sugar 6 g and lemon acid 0.06 g. The optimum stabilizer of the beverage is CMC-Na with 0.03% amount. 展开更多
关键词 Artemisia selengensis turoz Green tea Compound beverage Process-ina technoloqy Main technique points
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Strategies and Suggestions for the Development of Mechanized Rapeseed Production in Sichuan 被引量:1
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作者 蒋俊 蒲晓斌 +3 位作者 张锦芳 李浩杰 牛应泽 蒋梁材 《Agricultural Science & Technology》 CAS 2013年第10期1386-1391,共6页
Mechanization is the future direction of rapeseed production in Sichuan. A series of technology tests for rapeseed mechanized production have been carried out in terms of variety selection, key agronomic measures and ... Mechanization is the future direction of rapeseed production in Sichuan. A series of technology tests for rapeseed mechanized production have been carried out in terms of variety selection, key agronomic measures and machinery in the main production area of Sichuan in recent years. In the research, the agronomic techniques, including variety selection for mechanical production, key agronomic measures and mechanical harvesting were analyzed. Based on the present condi- tions, strategy and suggestions for the development of mechanized rapeseed produc- tion in Sichuan also were presented. 展开更多
关键词 RAPESEED Mechanized production Variety selection Agronomic mea- sures Policy guidance Development strategy
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Major Cultivation Technology of HQ No.1, a New Flue-cured Tobacco Cultivar
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作者 李文宇 李爱华 《Agricultural Science & Technology》 CAS 2015年第3期497-499,共3页
The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 1... The transplanting period, density, the number of left leaves and fertilizer amounts of HQ No.1 were explored in Hengyang. The results showed that with transplanting periods of March 5-March 15, and planting space of 120 cmx(50-60) cm, agronomic and economic characters of tobaccos showed insignificant differences. Specifically, plant height was growing upon the number of left leaf and fertilizer amount; tobacco yield and output value kept increasing upon fertilizer, and both reached maximums with pure N at 195 kg/hm^2, showing significant differences with the treatment of pure N at 135 kg/hm^2; the number of left leaf had the least effects on agronomic and economic characters of tobaccos. The research indicated that highly-qualified HQ No.1 can be produced, given that tobaccos are transplanted during March 10-March 15, planting density of 15 000-16 500 seedlings/hm^2, the number of left leaves of 22-24 leaves per seedling, and pure N of 150-165 kg/hm^2 in Hengyang. 展开更多
关键词 Flue-cured tobaccos HQ No.1 Major cultivation technology Agronomic characters Economic character Tolerance to disease
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High-Voltage MOSFETs in a 0.5μm CMOS Process
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作者 赵文彬 李蕾蕾 于宗光 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1268-1273,共6页
There is growing interest in developing high-voltage MOSFET devices that can be integrated with low-voltage CMOS digital and analog circuits. In this paper,high-voltage nand p-type MOSFETs are fabricated in a commerci... There is growing interest in developing high-voltage MOSFET devices that can be integrated with low-voltage CMOS digital and analog circuits. In this paper,high-voltage nand p-type MOSFETs are fabricated in a commercial 3.3/ 5V 0.5μm n-well CMOS process without adding any process steps using n-well and p-channel stops. High current and highvoltage transistors with breakdown voltages between 23 and 35V for the nMOS transistors with different laydut parameters and 19V for the pMOS transistors are achieved. This paper also presents the insulation technology and characterization results for these high-voltage devices. 展开更多
关键词 high-voltage MOSFET low-voltage MOSFET 0.5μm CMOS process embedded manufacture technology
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Thermal Treatment for Decreasing the Acidity of Crude Oil
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作者 申海平 王玉章 李锐 《Petroleum Science》 SCIE CAS CSCD 2004年第3期78-81,96,共5页
Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective a... Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective approach to decreasing acidity and the acid removal rate reaches 80%. Temperature is one of the main factors that determine the acid removal reaction. When the temperature ranges from 420oC to 440oC, the acid removal rate increases with the rise of the reaction temperature, but the increase slows down gradually. At the reaction temperature below 440oC, the long reaction time favors the acid removal. The cracking and polymerization of hydrocarbon molecules take place so that the properties of the crude oil change at the same time when the highly acidic crude is thermally treated. 展开更多
关键词 Highly acidic crude naphthenic acid acid removal thermal treatment VISBREAKING
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SCDI Flash Memory Device Ⅱ:Experiments and Characteristics
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作者 欧文 钱鹤 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期497-501,共5页
Step channel direct injection(SCDI) flash memory device is successfully achieved by 1 2μm CMOS technology,moreover good performance is obtained.At the bias condition of V g=6V, V d=5V,the programming speed ... Step channel direct injection(SCDI) flash memory device is successfully achieved by 1 2μm CMOS technology,moreover good performance is obtained.At the bias condition of V g=6V, V d=5V,the programming speed of SCDI device is 42μs.Under the condition of V g=-8V, V s=8V,the erasing speed is 24ms.Compared with the same size of conventional flash memory device whose corresponding parameters are 500μs and 24ms,respectively,the performance of SCDI device is remarkably improved.During manufacturing of SCDI device,the key technologies are to make the shallow step with appropriate depth and angle,along with eliminating the etch damage during the process of Si 3N 4 spacer. 展开更多
关键词 SCDI flash memory programming speed key technology
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Quantitative Description of the Effects of Sweep Efficiency and Displacement Efficiency during Chemical Flooding on a Heterogeneous Reservoir 被引量:6
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作者 沈平平 袁士义 +2 位作者 邓宝荣 宋杰 沈奎友 《Petroleum Science》 SCIE CAS CSCD 2004年第3期41-48,77,共9页
The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling softw... The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control. 展开更多
关键词 Chemical flooding displacement efficiency sweep efficiency recovery efficiency heterogenous reservoir
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Ultrasound-associated extraction of seed oil of Korean pine 被引量:37
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作者 ZHANGYing WANGZhen-yu CHENXiao-qiang 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第2期140-142,共3页
Experiment on ultrasound- associated extraction of seed oil of Korean pine(Pinus koraiensis) was conducted in Northeast Forestry University, Harbin, China. The factorsaffecting extraction yield, such as ultrasonic fre... Experiment on ultrasound- associated extraction of seed oil of Korean pine(Pinus koraiensis) was conducted in Northeast Forestry University, Harbin, China. The factorsaffecting extraction yield, such as ultrasonic frequency, extracting temperature, extracting timeand the ratio of material to liquid (ratio of Korean pine seed to absolute alcohol), were analyzedunder specific condition and the optimal extracting parameters were obtained as the ultrasonicfrequency 32 000 Hz, the extracting temperature 80 ℃, the extracting time 50 min, and the ratio ofmaterial to liquid 1: 30. The study demonstrates that ultrasound is a reliable and great efficiencytool for the fast extraction of Korean pine seed oil. 展开更多
关键词 ULTRASONIC EXTRACTION korean pine seed oil influencing factors
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Electroless Plating of Carbon Nanotubes with Copper 被引量:1
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作者 凤仪 袁海龙 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第5期728-731,共4页
A simple chemical method was employed to coat carbon nanotubes with a layer of copper. Due to the hydrophobic nature, large surface curvature, small diameter and large aspect ratio, it is difficult to gain continuous ... A simple chemical method was employed to coat carbon nanotubes with a layer of copper. Due to the hydrophobic nature, large surface curvature, small diameter and large aspect ratio, it is difficult to gain continuous electroless plating layer on the surface of carbon nanotubes. In this paper, a series methods (oxidization, sensitization and activation) are used to add active sites before electroless plating, and the adjustment of the traditional composition of copper electroless plating bath and operating condition can decelerate electroless plating rate. The samples before and after coating were analyzed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that the surface of carbon nanotubes was successfully coated with continuous layer of copper, which lays a good foundation for applying carbon nanotubes in composites. 展开更多
关键词 carbon nanotube electroless plating COPPER
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Research on Optimized Utilization of Naphtha Resources Based on Adsorptive Separation with Zeolite 被引量:8
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作者 Shen Benxian Liu Jichang, Wang Zhenxian (Petroleum Processing Research Center, East China University of Science and Technology, Shanghai 200237) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2005年第1期49-55,共7页
By means of molecular scale management, the technology of separating normal paraffins from naphtha through adsorption using 5A molecular sieves was studied with the purpose of optimizing the utilization of naphtha. Th... By means of molecular scale management, the technology of separating normal paraffins from naphtha through adsorption using 5A molecular sieves was studied with the purpose of optimizing the utilization of naphtha. The raw materials used in steam cracking and catalytic reforming processes could be allocated properly. During the adsorption process, the separation efficiency of the normal paraffins was above 99.9% with the purity of normal paraffins in the desorption oil exceeding 98.2%. With the use of the desorption oil as the feedstock of steam cracking, the ethylene yield increased from 29.7%-35.0% to 41.4%- 49.2% compared to that of the naphtha in the existing plant under similar operation conditions. The potential aromatic content of the raffinate oil rose from 30.6% to 43.5% compared to that in naphtha. The research octane number of the raffinate oil reached more than 85 with an increase of 20 units compared to that of naphtha, so the raffinate oil is more suitable for use as a blending component for high-octane clean gasoline. 展开更多
关键词 NAPHTHA n-paraffin ADSORPTION molecular scale management
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Study and Commercial Test on Technology for Deacidification of Distillate Oils 被引量:1
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作者 Tang Xiaodong An Rong +1 位作者 Cui Yingxian Du Hongyong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2005年第3期19-25,共7页
A new kind of solvent for deacidification of distillate oils was introduced in this paper. After successful laboratory study this technology had been applied in commercial scale successfully. Compared to traditional c... A new kind of solvent for deacidification of distillate oils was introduced in this paper. After successful laboratory study this technology had been applied in commercial scale successfully. Compared to traditional caustic wash of distillate oils, this technology has a lot of merits, such as the broad range of distillates to be processed, low caustic consumption, recycle of deacidifying agent, absence of waste caustic discharge, and low equipment revamp expenses, which can have promising perspectives for exploitation and application of this technology. 展开更多
关键词 distillate oil deacidifying agent petroleum acids purification process experimental study commercial application
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Preparation and microstructure of Al-Ni-Y powder by rapid solidification 被引量:1
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作者 黄劲松 刘咏 +1 位作者 陈仕奇 刘祖铭 《Journal of Central South University of Technology》 2004年第1期1-5,共5页
The Al-Ni-Y alloy powder was prepared by rapid solidification technology of inert gas atomization. The diameter of amorphous powder is less than 12 μm. The effects of atomization gas on cooling velocity, morphology,... The Al-Ni-Y alloy powder was prepared by rapid solidification technology of inert gas atomization. The diameter of amorphous powder is less than 12 μm. The effects of atomization gas on cooling velocity, morphology, microstructure and microhardness of powder and fine powder ratio were investigated.The results show that the morphology, microstructure and microhardness of powder and fine powder ratio are affected by cooling velocity changed through atomization gas. The cooling velocity of inert gas atomization is more than 1×10~4 K/s. The larger the cooling velocity, the finer the powder, and the smoother the surface of powder; the smaller the diameter of powder, the larger the microhardness of powder. 展开更多
关键词 rapid solidification AMORPHOUS POWDER
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Application of geographical information system technology to epidemiological surveillance and prevention and cure decision-making for SARS 被引量:1
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作者 姜建辉 屈景辉 +3 位作者 徐德忠 闫永平 张恒 张治英 《Journal of Medical Colleges of PLA(China)》 CAS 2006年第3期186-188,共3页
Objective:To expound geographical information system (GIS) technology is a very important tool when it was employed to assist to present the distribution by time and place and the model of transmission of infectious d... Objective:To expound geographical information system (GIS) technology is a very important tool when it was employed to assist to present the distribution by time and place and the model of transmission of infectious disease. Methods: We illustrated the assistant decision-making support function of GIS with an example of the spatial decision support system for SARS controlling in Shaanxi province of China which was developed by us. Results: The spatial decision support system established by applying GIS technology fulfilled the needs of real-time collection and management and dissemination SARS information and of surveillance and analysis the epidemic situation of SARS. Conclusion: Occurrence and epidemic of diseases, implement prevention and intervention measures and collocation hygienic resources are all with the characteristic of the variation of time and space, therefore, GIS technology has become a powerful tool for identifying risk factors of diseases, providing clues of causation of diseases , evaluating the effects of intervention measures and drawing a health management plan. 展开更多
关键词 geographical information system epidemiological surveillance spatial decision support system severe acute respiratory syndrome
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Separation and Purification of Dodecanedioic Acid from Its Homologous Compounds by Falling Film Crystallization 被引量:1
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作者 李裕 刘有智 齐雪琴 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第3期451-453,共3页
Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including cryst... Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including crystallizing time, flow rate of melt and temperature of glycerine bath, on purity of DDDA and crystallizing rate were investigated. Over 99% (by mole) DDDA was obtained for a feed composition of 96% (by mole). The main factors affecting the separation efficiency are flow rate of melt and temperature of glycerine bath. The crystallizing layer of DDDA was further purified by sweating and blasting. A set of optimized operation data are provided for better understanding the mechanism of heat and mass transfer in FFC, and for further industrial application of DDDA purification process. 展开更多
关键词 dodecanedioic acid homologous compound falling film crystallization SEPARATION PURIFICATION
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Characteristics of a Supersonic Swirling Dehydration System of Natural Gas 被引量:22
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作者 刘恒伟 刘中良 +2 位作者 冯永训 顾克宇 颜廷敏 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期9-12,共4页
A new type of dehydration unit for natural gas was briefly described and its basic structure and working principles were presented. An indoor test rig for testing the unit performance was set up and the experimental r... A new type of dehydration unit for natural gas was briefly described and its basic structure and working principles were presented. An indoor test rig for testing the unit performance was set up and the experimental results were given. The results showed that the unit could attain a maximum dew point depression of about 20℃ without any need of external mechanical power and chemicals. The pressure loss ratio, shock wave and the flow rate had great influence on the dehydration characteristics. From the systematic analysis of the factors that affect the dehydration efficiency of the unit, the suggestions for improving the unit are put forward. 展开更多
关键词 supersonic swirling separator DEHYDRATION natural gas
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Assessment on Commercial Application of Novel S-RHT Catalysts 被引量:1
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作者 Bian Fengming Wen Huixin(East-China University of Sceince and Technology, Shanghai 200237 2.SINOPEC MaomingBranch Company, Maoming 525011) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2004年第1期1-8,共8页
This article refers to the commercial application assessment of the novel S-RHT catalysts.The application outcome has shown that the catalysts loading was reduced with its performance kept at the original level at the... This article refers to the commercial application assessment of the novel S-RHT catalysts.The application outcome has shown that the catalysts loading was reduced with its performance kept at the original level at the initial and middle stages of operation. The performance of catalysts at the end of operation was analyzed, and factors affecting the performance of the novel catalysts at the end of run were identified to facilitate further improvement of the said catalysts. 展开更多
关键词 resid hydrotreating S-RHT catalyst commercial application evaluation
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Measurements of in situ stress and mining-induced stress in Beiminghe Iron Mine of China 被引量:8
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作者 欧阳振华 李长洪 +1 位作者 徐万才 李昊洁 《Journal of Central South University》 SCIE EI CAS 2009年第1期85-90,共6页
In order to obtain the distribution rules of in situ stress and mining-induced stress of Beiminghe Iron Mine, the stress relief method by overcoring was used to measure the in situ stress, and the MC type bore-hole st... In order to obtain the distribution rules of in situ stress and mining-induced stress of Beiminghe Iron Mine, the stress relief method by overcoring was used to measure the in situ stress, and the MC type bore-hole stress gauge was adopted to measure the mining-induced stress. In the in situ stress measuring, the technique of improved hollow inclusion cells was adopted, which can realize complete temperature compensation. Based on the measuring results, the distribution model of in situ stress was established and analyzed. The in situ stress measuring result shows that the maximum horizontal stress is 1.75-2.45 times of vertical stress and almost 1.83 times of the minimum horizontal stress in this mineral field. And the mining-induced stress measuring result shows that, according to the magnitude of front abutment pressure the stress region can be separated into stress-relaxed area, stress- concentrated area and initial stress area. At the -50 m mining level of this mine, the range of stress-relaxed area is 0-3 m before mining face; the range of stress-concentrated area is 3-55 m before mining face, and the maximum mining-induced stress is 16.5-17.5 MPa, which is 15-20 m from the mining face. The coefficient of stress concentration is 1.85. 展开更多
关键词 in situ stress mining-induced stress Beiminghe Iron Mine stress measurment
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Development Trends in Additive Manufacturing and 3D Printing 被引量:57
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作者 Bingheng Lu Dichen Li Xiaoyong Tian 《Engineering》 SCIE EI 2015年第1期85-89,共5页
Additive manufacturing and 3D printing tech-nology have been developing rapidly in the last 30 years, and indicate great potential for future development. The promising future of this technology makes its impact on tr... Additive manufacturing and 3D printing tech-nology have been developing rapidly in the last 30 years, and indicate great potential for future development. The promising future of this technology makes its impact on traditional industry unpredictable. 3D printing will propel the revolution of fabrication modes forward, and bring in a new era for customized fabrication by realizing the five "any"s: use of almost any material to fabricate any part, in any quantity and any location, for any industrial field. Innovations in material, design, and fabrication processes will be inspired by the merging of 3D-printing technology and processes with traditional manufacturing processes. Finally, 3D printing will become as valuable for manufacturing industries as equivalent and subtractive manufacturing processes. 展开更多
关键词 additive manufacturing 3D printing fabricationmodes customized fabrication innovative design
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