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Engineering an ultrathin amorphous TiO2 layer for boosting the weatherability of TiO2 pigment with high lightening power 被引量:3
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作者 Yangyang Yu Kejing Wu +9 位作者 Shiyu Lu Kui Ma Shan Zhong Hegui Zhang Yingming Zhu Jing Guo Hairong Yue Changjun Liu Siyang Tang Bin Liang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2825-2834,共10页
TiO2 pigments are typically coated with inert layers to suppress the photocatalytic activity and improve the weatherability. However, the traditional inert layers have a lower refractive index compared to TiO2, and th... TiO2 pigments are typically coated with inert layers to suppress the photocatalytic activity and improve the weatherability. However, the traditional inert layers have a lower refractive index compared to TiO2, and therefore reduce the lightening power of TiO2. In the present work, a uniform, amorphous, 2.9-nm-thick TiO2 protective layer was deposited onto the surface of anatase TiO2 pigments according to pulsed chemical vapor deposition at room temperature, with Ti Cl4 as titanium precursor. Amorphous TiO2 coating layers exhibited poor photocatalytic activity, leading to a boosted weatherability. Similarly, this coating method is also effective for TiO2 coating with amorphous SiO2 and SnO2 layers. However, the lightening power of amorphous TiO2 layer is higher than those of amorphous SiO2 and SnO2 layers. According to the measurements of photoluminescence lifetime, surface photocurrent density, charge-transfer resistance, and electron spin resonance spectroscopy, it is revealed that the amorphous layer can prevent the migration of photogenerated electrons and holes onto the surface, decreasing the densities of surface electron and hole, and thereby suppress the photocatalytic activity. 展开更多
关键词 TIO2 pigments Pulsed chemical vapor deposition ULTRATHIN LAYER WEATHERABILITY lightening POWER Photocatalytic suppression mechanism
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Edible Bird’s Nest, an Asian Health Food Supplement, Possesses Skin Lightening Activities: Identification of N-Acetylneuraminic Acid as Active Ingredient 被引量:9
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作者 Gallant Kar Lun Chan Zack Chun Fai Wong +5 位作者 Kelly Yin Ching Lam Lily Kwan Wai Cheng Laura Minglu Zhang Huangquan Lin Tina Tingxia Dong Karl Wah Keung Tsim 《Journal of Cosmetics, Dermatological Sciences and Applications》 2015年第4期262-274,共13页
Edible bird’s nest (EBN;Yan Wo), or cubilose, is originated from the salivary secretion of Aerodramus fuciphagus. In Asia, EBN is famous for its unproven skin lightening function. Here, we aim to reveal the active in... Edible bird’s nest (EBN;Yan Wo), or cubilose, is originated from the salivary secretion of Aerodramus fuciphagus. In Asia, EBN is famous for its unproven skin lightening function. Here, we aim to reveal the active ingredients of EBN responsible for skin lightening function. Three major fractions were isolated from EBN water extract by chromatography using LC-MS/MS, bioactivities of these isolated fractions were analyzed by assays of tyrosinase, melanocytes and 3D human skin model, from which, N-acetylneuraminic acid (NANA), the second isolated fraction showed an inhibition effect on tyrosinase activity in a dose-dependent manner. The IC50 of tyrosinase originated from mushroom and human was 16.93 mM and 0.10 mM respectively. Furthermore, only EBN with higher content of NANA (e.g. White and Red EBN), but not EBN with less NANA (e.g. Grass EBN), showed promising skin lightening function. This is the first report to reveal NANA being an active ingredient of EBN on skin lightening function. 展开更多
关键词 Cubilose N-Acetylneuraminic Acid Chemical Analysis SKIN lightening Human SKIN Model
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Application of unsteady flow simulation technology to lightening urban storm waterlogged disaster
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作者 周玉文 胡铭曾 戴亚非 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第2期7-9,共3页
The application of unsteady simulation to lightening urban storm waterlogged disaster involves six blocks: the main program, the database of drainage networks, the abstractions and losses block, the calculating inflow... The application of unsteady simulation to lightening urban storm waterlogged disaster involves six blocks: the main program, the database of drainage networks, the abstractions and losses block, the calculating inflow of sewer block, the drainage networks routing block and the waterlogged areas calculating block. This model can be used for simulating sewer surcharge and calculating area and water depth of waterlogged areas under storm conditions. The best design of rebuilding storm sewer system or combined sewer system can be provided by simulating existing state of built drainage pipeline. The model was used for rebuilding Shenyang drainage works last year, and the good results were obtained. 展开更多
关键词 URBAN drainage PIPELINE simulation model UNSTEADY flow lightening waterlogged DISASTER
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An Estimation Study to Determine the Percentage of Hydroquinone Levels in situ Skin Lightening Creams Using GC-MS and HPLC Spectroscopic Instruments
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作者 Maha Abdallah Alnuwaiser 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第6期1984-1987,共4页
Hydroquinone(HQ)is an phenolic aromatic compound used in cosmetic medicine as skin lightening material since long time ago.Accordingly the several pathological conditions that observed,the use of HQ for this purpose w... Hydroquinone(HQ)is an phenolic aromatic compound used in cosmetic medicine as skin lightening material since long time ago.Accordingly the several pathological conditions that observed,the use of HQ for this purpose was recently contraindicated.The commonly noted health problem associated with hydroquinone use was contact dermatitis.The present study was designed and conducted to determine the HQ presence and concentrations in ten samples of skin lightening cosmetics available in the local market.GC-MS analysis was employed for detection of HQ qualitatively while HPLC analysis was used as a quantitative analysis for determination of the HQ concentrations in each sample.The results obtained indicated that the overall range of HQ levels in all respected samples ranged from 0.0039%to 0.14%. 展开更多
关键词 Skin lightening COSMETICS HYDROQUINONE GC-MS HPLC Assay
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Optical Fiber Lightening for Fluorescence Signal Detection with Thermal Stability in Dentistry
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作者 Joo Beom Eom In Hee Shin +1 位作者 Hyeong Ju Park Byeong-Il Lee 《Journal of Biomedical Science and Engineering》 2015年第3期201-206,共6页
Dental caries diagnosis system has been made with a fiber lighting, camera module and band pass filter. By simply aligning a 405 nm LED (Light Emitting diode) chips directly connected polymer fibers, a compact lightin... Dental caries diagnosis system has been made with a fiber lighting, camera module and band pass filter. By simply aligning a 405 nm LED (Light Emitting diode) chips directly connected polymer fibers, a compact lighting for dental fluorescence imaging could be implemented. Special designed fiber holder with proper hole diameter was fabricated to directly connect polymer fibers with 1 mm fiber diameter and increased coupling efficiency between fibers and LEDs. Fibers connected to fiber holder were polished by polishing machine to reduce insertion loss of the fiber. Experimentally, an optical insertion loss of the fiber bundle of up to 0.8 dB was achieved. Further, LED array module was packaged with equally spaced LED chips with fiber holder on metal. Fiber lightening was fabricated with directly coupled between LED array module and fiber bundle by UV epoxy without focusing lens in order to lower the lightening temperature of intraoral camera in the human mouth. The measured temperature of fabricated fiber lightening was about 25 degree celcius. To achieve a fluorescence image and dental caries diagnosis, the proper optical filter, camera module, 405 nm fiber bundle lighting and software were investigated. The performance of the fluorescence intraoral camera with fiber lightening is confirmed by fluorescence image of human tooth. 展开更多
关键词 FLUORESCENCE LEDS DENTAL CARIES Fiber lightening
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Burden on Governments to Be Lightened
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《China Today》 1999年第11期63-63,共1页
关键词 BE Burden on Governments to Be lightened
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Effect of Lightening Hole on Dynamic Characteristics and Fatigue Life of Diesel Engine Crankshaft
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作者 YANG Fang REN Xiao-le CUI Ju-jie 《International Journal of Plant Engineering and Management》 2017年第2期95-101,共7页
As the core components of diesel engine,the structure and dynamic characteristics of the crankshaft has a vital role on engine performance. To Process the lightening hole with properly size in a certain location can r... As the core components of diesel engine,the structure and dynamic characteristics of the crankshaft has a vital role on engine performance. To Process the lightening hole with properly size in a certain location can reduce the weight of the crankshaft so as to,improve the dynamic characteristics and the connecting rod load of the crankshaft. Using finite element method and using three-dimensional software to model,the structural static and dynamic analysis theory to are gotten the performance and fatigue life analysis of crankshaft which have lightening hole with appropriate size. In this paper,to select the lightening hole for 25 mm size to analyze and compare the results with no hole of crankshaft analysis data can get that lightening hole can improve the crankshaft strength and the fatigue life of some location of the crankshaft. 展开更多
关键词 CRANKSHAFT lightening hole dynamic characteristics FATIGUE
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Lightening Optimization for 200 km/h AC Locomotive Body under Static Strength
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作者 付贵鑫 方卫宁 《铁道机车车辆》 2008年第B12期183-186,共4页
机车车体轻量化可以减少列车运行阻力,降低列车牵引功率,提高速度,改善列车的运行品质。近几年我国高速铁路的蓬勃发展,对机车车体轻量化的要求也越来越高。结合大同机车厂200km/h交流传动机车设计项目,在充分调研国内外机车轻量... 机车车体轻量化可以减少列车运行阻力,降低列车牵引功率,提高速度,改善列车的运行品质。近几年我国高速铁路的蓬勃发展,对机车车体轻量化的要求也越来越高。结合大同机车厂200km/h交流传动机车设计项目,在充分调研国内外机车轻量化研究现状的基础上提出了超拉丁方实验设计和可行方向法相结合的组合优化策略,并应用此方法对车体承载结构进行了轻量化优化,随后通过有限元强度分析来验证优化结果。结果证明,与传统方法相比,该方法对于求解类似非线性大型复杂结构的轻量化问题具有求解效率高和求解精度好等优点,具有广泛的应用前景。 展开更多
关键词 优化设计 轻量化 机车 超拉丁方 可行方向法
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重芳烃轻质化工艺技术研究进展 被引量:1
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作者 徐浩 《炼油与化工》 CAS 2024年第3期1-4,共4页
重芳烃一般是炼化企业副产的C_(9)^(+)单环及双环芳烃,利用重芳烃轻质化技术可以生产高附加值的三苯(BTX)物质。文中主要概述了重芳烃轻质化工艺技术原理和国内外研究现状,通过综合分析主要工艺技术的优缺点,提出了重芳烃轻质化工艺技... 重芳烃一般是炼化企业副产的C_(9)^(+)单环及双环芳烃,利用重芳烃轻质化技术可以生产高附加值的三苯(BTX)物质。文中主要概述了重芳烃轻质化工艺技术原理和国内外研究现状,通过综合分析主要工艺技术的优缺点,提出了重芳烃轻质化工艺技术未来研究重心在于开发更多廉价、绿色、高效且可工业化应用的催化剂和开发更高效的组合工艺。 展开更多
关键词 重芳烃 轻质化 催化剂 工艺技术 反应机理
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水稻淹水萌发对低氧胁迫的适应及其机制研究进展 被引量:2
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作者 张静 孙炳蕊 +8 位作者 毛兴学 江立群 吕树伟 陈文丰 范芝兰 于航 陈平丽 刘清 李晨 《植物遗传资源学报》 CSCD 北大核心 2024年第1期13-20,共8页
水稻是我国最重要的粮食作物之一,水稻生产是国家粮食安全的重要保障。传统移栽种植模式对我国的水稻增产、农民增收、农业发展起到了重要作用。但随着社会经济发展和产业要素变革,农村劳动力大幅减少,迫切需求轻简化的生产方式。水稻... 水稻是我国最重要的粮食作物之一,水稻生产是国家粮食安全的重要保障。传统移栽种植模式对我国的水稻增产、农民增收、农业发展起到了重要作用。但随着社会经济发展和产业要素变革,农村劳动力大幅减少,迫切需求轻简化的生产方式。水稻淹水直播能节省劳力、节约资源、有效降低杂草危害,是一种高效、经济和节约型的轻简栽培模式,在当前有较高的推广价值。淹水萌发时低氧胁迫造成的出苗率低是阻碍水稻淹水直播的首要因素,丰富的水稻种质资源中存在耐淹水萌发优异资源和基因,挖掘和利用这些优异资源和基因并培育适宜淹水直播的水稻新品种,是突破目前直播稻推广和应用瓶颈的关键。本文围绕水稻淹水萌发的生理特点、鉴定评价方法、优异种质鉴定、遗传规律、响应机制研究以及功能基因的育种应用等方面的研究进展进行综述,以期为水稻耐淹水萌发的机制研究和萌发耐淹品种的选育提供参考。 展开更多
关键词 水稻淹水直播 低氧胁迫 种子萌发 轻简栽培
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加氢裂化装置原料轻质化对反应过程影响研究 被引量:1
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作者 陈光 《炼油技术与工程》 CAS 2024年第6期18-21,共4页
在加氢裂化装置原料轻质化的背景下,考察了蜡油中掺炼不同比例直馏柴油对加氢裂化产品分布及产品性质的影响。当直馏柴油掺炼比例为45%(质量分数,下同)时,喷气燃料收率最高,达到26%。随着直馏柴油掺炼比例的增加,重石脑油的环烷烃、芳... 在加氢裂化装置原料轻质化的背景下,考察了蜡油中掺炼不同比例直馏柴油对加氢裂化产品分布及产品性质的影响。当直馏柴油掺炼比例为45%(质量分数,下同)时,喷气燃料收率最高,达到26%。随着直馏柴油掺炼比例的增加,重石脑油的环烷烃、芳烃含量降低;喷气燃料烟点呈逐渐升高的趋势;尾油(大于260℃)的链烷烃含量呈逐渐升高的趋势,环烷烃、芳烃含量呈逐渐降低的趋势,BMCI值(芳烃指数)呈先升高后降低的趋势。当直馏柴油掺炼比例为75%时,喷气燃料烟点最高,为28.8 mm。以掺炼15%直馏柴油的蜡油为原料时,随着转化率的升高,尾油的BMCI值逐渐降低;当尾油收率为20%时,尾油的BMCI值低至7.2,链烷烃质量分数升至62.0%,环烷烃质量分数降至35.2%,芳烃质量分数仅为2.6%。 展开更多
关键词 加氢裂化装置 原料轻质化 反应过程 直馏柴油 产品分布 产品性质 转化率 加氢裂化尾油
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Characteristics of Mercury Intoxication Induced by Skin-lightening Products 被引量:1
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作者 Gui-Fang Sun Wen-Tao Hu +2 位作者 Zhi-Hao Yuan Bo-Ai Zhang Hong Lu 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第24期3003-3004,共2页
Mercury is usually added to skin-lightening products due to its whitening effect.The Food and Drug Administration (FDA) limits the amount of mercury in cosmetics to trace amounts under 1 ppm.Nevertheless,many cosmet... Mercury is usually added to skin-lightening products due to its whitening effect.The Food and Drug Administration (FDA) limits the amount of mercury in cosmetics to trace amounts under 1 ppm.Nevertheless,many cosmetics contain mercury above 1000 ppm to increase the whitening effect.In a group of special patients in the study,pain,renal damage,and neuropsychiatric symptoms were the cardinal symptoms observed. 展开更多
关键词 MERCURY PAIN Psychiatric Symptoms Renal Damage Skin-lightening Products
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含鞣花酸组合物的唇部化妆品淡化唇纹功效评价
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作者 张明 王煚 《香料香精化妆品》 CAS 2024年第1期12-16,共5页
选择具有抗皱作用的鞣花酸组合物,制备了具有淡化唇纹的润唇膏。运用人体试验法对所制备的含鞣花酸组合物的润唇膏进行功效性评价,选择110名受试者为研究对象,按要求在下嘴唇右侧使用润唇膏4周,测试受试者使用前后皮肤粗糙度和皮肤皱纹... 选择具有抗皱作用的鞣花酸组合物,制备了具有淡化唇纹的润唇膏。运用人体试验法对所制备的含鞣花酸组合物的润唇膏进行功效性评价,选择110名受试者为研究对象,按要求在下嘴唇右侧使用润唇膏4周,测试受试者使用前后皮肤粗糙度和皮肤皱纹深度的抗皱功效参数。结果表明含鞣花酸组合物的唇部化妆品具有降低皮肤粗糙度、淡化唇纹的效果。 展开更多
关键词 鞣花酸 稻米油 乙酸异丁酸蔗糖酯(SAIB) 米糠蜡 淡化唇纹 人体试验法
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基于分子筛的重芳烃轻质化利用技术进展
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作者 柴涵语 徐亚荣 +2 位作者 魏书梅 王冰 周升侠 《炼油与化工》 CAS 2024年第5期14-17,共4页
现代化工行业中,由于催化重整、蒸汽裂解生产乙烯等装置不断扩能,导致重芳烃产量巨大,其组分复杂且难以分离,利用率极低,重质芳烃轻质化技术在未来发展尤为关键。文中阐述了国内外重质芳烃轻质化技术研究中的3种反应类型,证明了基于分... 现代化工行业中,由于催化重整、蒸汽裂解生产乙烯等装置不断扩能,导致重芳烃产量巨大,其组分复杂且难以分离,利用率极低,重质芳烃轻质化技术在未来发展尤为关键。文中阐述了国内外重质芳烃轻质化技术研究中的3种反应类型,证明了基于分子筛改性对轻质化技术的重要性,分析了在重芳烃轻质化的工业应用中面临的挑战与未来展望,为企业绿色化发展提供研究依据。 展开更多
关键词 重质芳烃 轻质化 分子筛催化剂
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广播电视工程中的接地技术应用研究
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作者 徐胜堂 《电声技术》 2024年第5期7-10,共4页
随着广播电视领域的不断进步,接地技术在广播电视工程中扮演着至关重要的角色。详细分析广播电视工程中的接地技术,包括避雷接地、保护接地、屏蔽接地以及信号接地,并探讨了这些技术在大型广播电视发射台、广播电视天线及室内接地中的... 随着广播电视领域的不断进步,接地技术在广播电视工程中扮演着至关重要的角色。详细分析广播电视工程中的接地技术,包括避雷接地、保护接地、屏蔽接地以及信号接地,并探讨了这些技术在大型广播电视发射台、广播电视天线及室内接地中的具体应用。通过分析现代接地技术面临的挑战与发展趋势,为广播电视工程中接地技术的优化提供科学合理的建议,以提升系统的安全性和稳定性。 展开更多
关键词 防雷接地 保护接地 屏蔽接地 信号接地 广播电视工程
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为基层减负赋能的实践探索
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作者 肖健 《石油化工管理干部学院学报》 2024年第2期6-10,共5页
习近平总书记强调,对形式主义、官僚主义要毫不妥协,全面检视、靶向纠治,持续为基层松绑减负。党中央也连续5年对“为基层减负工作”进行了专门的部署和推动。地面工程建设监督中心在胜利油田党委的正确领导下,高度重视为基层减负这项工... 习近平总书记强调,对形式主义、官僚主义要毫不妥协,全面检视、靶向纠治,持续为基层松绑减负。党中央也连续5年对“为基层减负工作”进行了专门的部署和推动。地面工程建设监督中心在胜利油田党委的正确领导下,高度重视为基层减负这项工作,不断从思想观念、工作作风和领导方法上找根源、抓整改,逐步在价值流、管理流、业务流和监督流建立健全了为基层减负赋能的长效工作机制,使基层从无谓的事务中解脱出来,将更多时间和精力投入主责主业,取得了较好成效。 展开更多
关键词 基层减负 主责主业 党建 实践探索
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“双减”背景下义务教育阶段教育改革的特点与实践——以北京市顺义区“双减”工作实践探索为例
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作者 周靖彦 《基础教育参考》 2024年第4期73-80,共8页
减轻学生过重负担,提升教学质量,一直是义务教育阶段的工作目标。新中国成立以来,我国出台了一系列教育领域减负政策,并经历了以教育部下发首部教育减负政策《关于减轻中小学生过重负担的指示》为标志的起步时期,到将减负目标融入到课... 减轻学生过重负担,提升教学质量,一直是义务教育阶段的工作目标。新中国成立以来,我国出台了一系列教育领域减负政策,并经历了以教育部下发首部教育减负政策《关于减轻中小学生过重负担的指示》为标志的起步时期,到将减负目标融入到课程改革目标任务中共同落实的发展时期,再到确立减负问题为社会问题,倡导各部门协同发力,全方位教育减负的新时期三个阶段。“双减”是党中央立足中华民族千秋伟业和学生全面发展的一项重大教育改革。“双减”政策摒弃过去的线性思维,不仅关注课时、作业、考试等问题,同时强调源头治理、系统治理、综合治理。北京市顺义区在认真分析“双减”政策颁布后北京市贯彻落实的总体情况特点后,聚焦学校教书育人主体作用发挥,从课堂教学质量提升、课后服务提质增效、课题深度研究、研究成果转化等方面,有效落实“双减”政策,践行立德树人初心使命的实践探索。 展开更多
关键词 义务教育 减负 “双减”政策 教师素养 立德树人
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重芳烃轻质化精馏系统操作压力的优化
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作者 刘亭引 《节能》 2024年第6期45-48,共4页
精馏是化工中重要的工艺单元,其能耗在装置中占据一定的比例。简述压力对精馏工艺的影响,通过适当调节精馏压力达到节能降耗目的。以国内某重质芳烃轻质化开发项目的脱C_6/C_7塔为例,通过提高脱C_6/C_7塔压力由0.1 MPa(g)至1.05 MPa(g)... 精馏是化工中重要的工艺单元,其能耗在装置中占据一定的比例。简述压力对精馏工艺的影响,通过适当调节精馏压力达到节能降耗目的。以国内某重质芳烃轻质化开发项目的脱C_6/C_7塔为例,通过提高脱C_6/C_7塔压力由0.1 MPa(g)至1.05 MPa(g),提高塔顶冷凝温度,精馏系统可多副产1.20 MPa(g)蒸汽,进而提高经济效益。从整个精馏系统进行考察能源消耗情况,利用化工模拟软件ASPEN进行核算。经计算表明,脱C_6/C_7塔压力优化后,系统可多副产1.20 MPa蒸汽11.53 t/h,年节约运行费用637.33万元,投资增加221.7万元,经济效益十分显著。 展开更多
关键词 精馏分离系统 重质芳烃轻质化 节能优化 ASPEN
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Lighten Up
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作者 TANG YUANKAI 《Beijing Review》 2006年第9期40-41,共2页
China's resolve to embrace energy-efficient lighting unleashes a powerful market potential While a lot of attention has been focused on China's energy shortage, there seemed to be little emphasis on making lig... China's resolve to embrace energy-efficient lighting unleashes a powerful market potential While a lot of attention has been focused on China's energy shortage, there seemed to be little emphasis on making lighting, which consumes as much as 12 percent of the electricity produced in the country, more energy efficient. Until fairly recently, that is. The Chinese Government and companies are promoting the use of 展开更多
关键词 lighten Up
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Tax Burden on Industry Lightened in China
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作者 Xinhua 《World Economy & China》 1995年第2期21-21,共1页
TaxBurdenonIndustryLightenedinChina¥XinhuaIndustrialenterprisesarefeelinglessofapinchfromtaxessincetaxreform... TaxBurdenonIndustryLightenedinChina¥XinhuaIndustrialenterprisesarefeelinglessofapinchfromtaxessincetaxreformswereimplementede... 展开更多
关键词 Tax Burden on Industry lightened in China
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