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Design of packing cup interference fit value of hypercompressors for low density polyethylene production
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作者 Da LEI Xuehong LI +1 位作者 Yun LI Xiwen REN 《能源前沿:英文版》 CSCD 2019年第1期107-113,共7页
The hypercompressor is one of the core facilities in low density polyethylene production,with a discharge pressure of approximately 300 MPa.A packing cup is the basic unit of cylinder packing,assembled by the interfer... The hypercompressor is one of the core facilities in low density polyethylene production,with a discharge pressure of approximately 300 MPa.A packing cup is the basic unit of cylinder packing,assembled by the interference fit between an inner cup and an outer cup.Because the shrink-fitting prestresses the packing cup,serious design is needed to gain a favorable stress state,for example,a tri-axial compressive stress state.The traditional method of designing the interference fit value for packing cups depends on the shrink-fit theory for thickwalled cylinder subject to internal and external pressure.According to the traditional method,critical points are at the inner radii of the inner and external cup.In this study,the finite element method(FEM)has been implementcd to determine a more accurate stress level of packing cups.Different critical points have been found at the edge of lapped sealing surfaces between two adjacent packing cups.The maximum Von Mises equivalent stress in a packing cup increases after a decline with the rise of the interference fit value.The maximum equivalent stress initially occurs at the bore of the inner cup,then at the edge of lapped mating surfaces,and finally at the bore of the outer cup,as the interference radius increases.The traditional method neglects the influence of axial preloading on the interference mating pressure.As a result,it predicts a lower equivalent stress at the bore of the external cup.A higher interference fit value accepted by the traditional method may not be feasible as it might already make packing cups yield at the edge of mating surfaces or the bore of the external cup.Along with fatigue analysis,the feasible range of interference fit value has been modified by utilizing FEM.The modified range tends to be narrower and safer than the one derived from the traditional method,after getting rid of shrink-fit values that could result in yielding in a real packing cup. 展开更多
关键词 INTERFERENCE FIT VALUE PACKING CUP hypercompressor finite element method(FEM)
倾斜防尘水杯 预览
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《学苑创造:B版》 2019年第1期44-46,共3页
每次喝完水,空着的无盖杯子容易沾上灰尘,如何才能方便又卫生地存放空置的杯子,使杯子能够一直保持清洁呢?这样的问题可难不倒设计师们。“Bevel Cup”巧妙地利用了力学的原理,在杯子的手柄上做文章,使杯子与桌面保持45度倾斜的角度倒... 每次喝完水,空着的无盖杯子容易沾上灰尘,如何才能方便又卫生地存放空置的杯子,使杯子能够一直保持清洁呢?这样的问题可难不倒设计师们。“Bevel Cup”巧妙地利用了力学的原理,在杯子的手柄上做文章,使杯子与桌面保持45度倾斜的角度倒放。斜着倒放的杯子,不仅能避免灰尘进入杯子,还能沥干杯子中的液体,杯口也不会和桌面直接接触,可以最大程度地保持杯子的清洁。 展开更多
关键词 水杯 防尘 杯子 设计师 CUP 灰尘 桌面 力学
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三个“一”看懂首届J80亚洲锦标赛
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作者 李旻(图) 《游艇业》 2019年第1期50-53,共4页
2018年12月6-10日,首届“天泽航海杯”J80亚洲锦标赛在厦门五缘湾举行。这项赛事由中国帆船帆板运动协会、J80帆船亚洲联合会、厦门市体育局联合主办,厦门市帆船游艇运动协会承办,天泽航海俱乐部冠名赞助,来自10个国家和地区的26个帆船... 2018年12月6-10日,首届“天泽航海杯”J80亚洲锦标赛在厦门五缘湾举行。这项赛事由中国帆船帆板运动协会、J80帆船亚洲联合会、厦门市体育局联合主办,厦门市帆船游艇运动协会承办,天泽航海俱乐部冠名赞助,来自10个国家和地区的26个帆船队参加比赛(包括9支高校队伍)。 展开更多
关键词 MARINE 锦标赛 亚洲 CUP 厦门市 帆船 俱乐部 航海
Effect of Ciprofloxacin on S.aureus and E.coli Growth in Presence of Vitamin C Using Cup Cut Diffusion Method 预览
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作者 Suhera M. Aburawi Bassma M. Doro Ebtisam A. Awad 《药剂与药理学:英文版》 2019年第8期473-484,共12页
Ciprofloxacin is a second-generation of fluoroquinolone,broad-spectrum antibiotic with bactericidal activity against Gram-positive and Gram-negative organisms.It is one of the most widely used antibiotics,because of i... Ciprofloxacin is a second-generation of fluoroquinolone,broad-spectrum antibiotic with bactericidal activity against Gram-positive and Gram-negative organisms.It is one of the most widely used antibiotics,because of its efficacy,safety,and relatively low cost.Ascorbic acid(vitamin C)is water-soluble monosaccharide antioxidant;it is essentially required by the body for its various biochemical and physiological processes.S.aureus is Gram-positive cocci;widely distributed in the environment,it is a member of the normal flora of the body.S.aureus is not always pathogenic;it is a common cause of skin infections including abscesses,respiratory infections such as sinusitis,and food poisoning.E.coli is Gram-negative bacteria,found in the environment,foods,and intestines.Most E.coli strains are harmless;it is part of the normal microbiota of the gut.However,some serotypes of E.coli cause serious food poisoning in their hosts;it can cause diarrhea,while others cause urinary tract infections,respiratory illness and pneumonia,and other illnesses.Method:Cup cut diffusion method was applied.Experiment I:is carried out to choose the concentration of vitamin C to be used in experiment II.The negative control is normal saline,added in cup in each plate,vitamin C(100 mg/mL,200 mg/mL,400 mg/mL)was added,the volume in each cup was 100μL.Experiment II:Eight groups of treatments were applied.The first is the negative control(1%normal saline),the second group is the positive control of vitamin C(200 mg/mL).The third,fourth and fifth groups are ciprofloxacin with different concentrations(10 mg/mL,20 mg/mL,40 mg/mL);the sixth,seventh and eighth are the combination of vitamin C with each concentration of ciprofloxacin(10 mg/mL,20 mg/mL,40 mg/mL).Each group includes six petri dishes.Bacterial plates were incubated at 37 oC for 24 h and 48 h.Zone of inhibition is measured in mm.Results and conclusion:Ciprofloxacin produces dose dependent increase in zone of inhibition of S.aureus and E.coli growth,after 24 and 48 hours incubation.While vit 展开更多
关键词 CIPROFLOXACIN VITAMIN C S.aureus E.COLI CUP CUT diffusion method
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没有威尼斯人的澳门帆船假期
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《游艇业》 2019年第1期30-33,共4页
2019粤港澳大湾区杯帆船赛暨澳门杯国际帆船赛由澳门体育局和纵横四海航海赛事管理主办,澳门海事及水务局、澳门风帆船总会协办,于1月10日至13日举行,分为IRC组和博纳多40.7组两个组别各10艘船,共20艘参赛,最终万博鱼航海队、符腾堡帆... 2019粤港澳大湾区杯帆船赛暨澳门杯国际帆船赛由澳门体育局和纵横四海航海赛事管理主办,澳门海事及水务局、澳门风帆船总会协办,于1月10日至13日举行,分为IRC组和博纳多40.7组两个组别各10艘船,共20艘参赛,最终万博鱼航海队、符腾堡帆船俱乐部队分别夺得IRC组、40.7组冠军,老潘所在船队获得40.7组第六名,最好成绩单日第三。 展开更多
关键词 帆船 澳门 CUP 威尼斯 IRC 粤港澳 水务局 航海
日清食品杯面容器要采用植物性塑料 预览
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《科技传播》 2019年第12期I0004-I0005,共2页
日清食品控股将把杯面的容器改为源自植物的塑料。日清将在CUP NOODLE的容器上使用一至两成源自甘蔗的植物性树脂“生物质聚乙烯”。据分析,源自植物的塑料燃烧后大气中的二氧化碳总量不会改变。据悉新型容器从生产到焚烧的二氧化碳排... 日清食品控股将把杯面的容器改为源自植物的塑料。日清将在CUP NOODLE的容器上使用一至两成源自甘蔗的植物性树脂“生物质聚乙烯”。据分析,源自植物的塑料燃烧后大气中的二氧化碳总量不会改变。据悉新型容器从生产到焚烧的二氧化碳排放量比现有容器减少近两成。 展开更多
关键词 容器 塑料 物性 食品 二氧化碳排放 CUP 聚乙烯 生物质
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冬日鏖战 记Honda Cup暴锋眼190统一赛 预览
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作者 本刊编辑部 《摩托车》 2019年第2期92-93,共2页
在2018年的最后几天里,你会选择以哪种方式辞旧迎新?对车手们来说,和家人、爱人一起度过固然温馨浪漫,但和自己心爱的赛车、和亦师亦友的一群赛车爱好者一起度过似乎更有深意,尤其是在寒潮来袭的时节里……12月29日~30日,2018年Honda Cu... 在2018年的最后几天里,你会选择以哪种方式辞旧迎新?对车手们来说,和家人、爱人一起度过固然温馨浪漫,但和自己心爱的赛车、和亦师亦友的一群赛车爱好者一起度过似乎更有深意,尤其是在寒潮来袭的时节里……12月29日~30日,2018年Honda Cup暴锋眼190统一赛在位于肇庆的广东国际赛车场举行,25位来自祖国各地的车手相聚在这里,为了对赛车共同的执念和痴情,以这样激动人心的独特方式和2018年说再见. 展开更多
关键词 HONDA CUP
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Let the Games Begin Who will emerge as winners of CAN 2019?
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作者 Eric Vincent Fomo 《中国与非洲:英文版》 2019年第6期42-43,共2页
This year's Africa Cup of Nations (CAN) featuring 24 teams promises to be an exciting affair. The action will kick off on June 21 at the Cairo International Stadium in Egypt. A review of the strengths and chances ... This year's Africa Cup of Nations (CAN) featuring 24 teams promises to be an exciting affair. The action will kick off on June 21 at the Cairo International Stadium in Egypt. A review of the strengths and chances of each nation makes interesting reading. Having qualified 22 times and won seven titles, the Pharaohs of Egypt reign over CAN. As the 2019 venue, Egypt will also be the first nation to have organized the competition on five occasions. As a replacement country for original hosts Cameroon, which was not able to complete preparations in time, Egypt offers 10 stadiums of international standard, one of which, the 75,000- seat Cairo International Stadium, has already held the finals in 1974,1986 and 2006. 展开更多
关键词 GAMES BEGIN CAN 2019 CUP of Nations
Occupations Behind the World Cup 预览
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作者 Jenny Hu 《中国对外贸易:英文版》 2018年第4期43-45,共3页
The quadrennial World Cup begins in the hot summer of July,which is not only the carnival day for the fans,but also brings business opportunities to the“World Cup Economy”.The rise of the E-commerce platforms sellin... The quadrennial World Cup begins in the hot summer of July,which is not only the carnival day for the fans,but also brings business opportunities to the“World Cup Economy”.The rise of the E-commerce platforms selling crayfish has spawned a new profession,crayfish tasters,who work overtime until early morning to eat crayfish during the World Cup;night snack is necessary while watching the game,so the increase in the orders promises the delivery mena“monthly salary over 10,000 RMB”;the number of the fans of sports Taobao anchors increases significantly,many of whom have changed their schedule to Russian time;without the help of Chinese women workers,the mascot of the World Cup might not appear on the opening ceremony on time. 展开更多
关键词 World CUP World CUP ECONOMY
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铁道车辆单元制动缸用耐低温橡胶皮碗的研制 预览
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作者 高新文 王付胜 +1 位作者 曹江勇 马宗斌 《橡胶工业》 CAS 2018年第3期318-321,共4页
研究丁腈橡胶(NBR)牌号、补强体系和增塑体系对NBR胶料耐低温性能的影响,根据试验结果优化耐低温橡胶皮碗胶料配方,采用优化配方制造橡胶皮碗并进行产品性能试验。结果表明:优化配方胶料和皮碗除具有优异的耐低温性能外,其他各项性... 研究丁腈橡胶(NBR)牌号、补强体系和增塑体系对NBR胶料耐低温性能的影响,根据试验结果优化耐低温橡胶皮碗胶料配方,采用优化配方制造橡胶皮碗并进行产品性能试验。结果表明:优化配方胶料和皮碗除具有优异的耐低温性能外,其他各项性能均满足技术要求,且所研制的橡胶皮碗能通过低温运用考验。 展开更多
关键词 丁腈橡胶 皮碗 耐低温性能 单元制动缸
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Colonoscopy attachments for the detection of precancerous lesions during colonoscopy:A review of the literature 预览
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作者 Paraskevas Gkolfakis Georgios Tziatzios +2 位作者 Eleftherios Spartalis Ioannis S Papanikolaou Konstantinos Triantafyllou 《世界胃肠病学杂志:英文版》 SCIE CAS 2018年第37期4243-4253,共11页
Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions,it remains an imperfect examination,as it can fail in detecting u... Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions,it remains an imperfect examination,as it can fail in detecting up to almost one fourth of existing adenomas.Among reasons accounting for such failures,is the inability to meticulously visualize the colonic mucosa located either proximal to haustral folds or anatomic curves,including the hepatic and splenic flexures.In order to overcome these limitations,various colonoscope attachments aiming to improve mucosal visualization have been developed.All of them-transparent cap,Endocuff,Endocuff Vision and Endorings-are simply mounted onto the distal tip of the scope.In this review article,we introduce the rationale of their development,present their mode of action and discuss in detail the effect of their implementation in the detection of lesions during colonoscopy. 展开更多
关键词 ADENOMA DETECTION RATE ADENOMA MISS RATE COLONOSCOPY Cup Endocuff Endocuff Vision Endorings
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气力托勺式马铃薯精量排种器设计 预览
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作者 侯加林 刘威 +3 位作者 张万枝 吕金庆 吕钊钦 张智龙 《农业工程学报》 CSCD 北大核心 2018年第24期18-28,共11页
针对勺带式排种器播种前进速度进一步提高的限制以及气吸式排种器播种马铃薯所需功耗较大等问题,设计了一种气力托勺式马铃薯精量排种器。气力托勺式马铃薯精量排种器主要由滚筒、托勺、种箱、空心轴、气压隔板、压缩弹簧、链轮、清种... 针对勺带式排种器播种前进速度进一步提高的限制以及气吸式排种器播种马铃薯所需功耗较大等问题,设计了一种气力托勺式马铃薯精量排种器。气力托勺式马铃薯精量排种器主要由滚筒、托勺、种箱、空心轴、气压隔板、压缩弹簧、链轮、清种气管等部件组成。通过理论分析与计算,确定了排种器关键部件参数。为了确定气力托勺式马铃薯精量排种器作业的优化参数,以负压、清种风速、型孔直径、滚筒转速为试验因素,以漏播率、合格率为试验指标,采用Box-Behnken试验设计原理进行了排种器性能试验,得到影响漏播率和合格率的主次顺序为负压、滚筒转速、型孔直径和清种风速。利用数据处理软件Design Expert8.0.6进行参数优化,以漏播率、合格率为试验指标,得出负压为8.92kPa,清种风速为32.25m/s,型孔直径为18.34mm,滚筒转速为19.92r/min时,模型预测的漏播率为3.64%,合格率为91.9%。经过试验验证,与优化结果基本一致。论文相关研究可为马铃薯精量播种技术的研究提供参考。 展开更多
关键词 农业机械 农作物 设计 马铃薯 排种器 托勺 气吸
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商业动态
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《经理人》 2018年第4期76-77,共2页
米其林超高性能轮胎亮相日内瓦 全新法拉利488 Pista顶级超跑在日内瓦车展亮相,而米其林作为其专用供应商,也为其装备了最新定制的超高性能轮胎米其林Pilot Sport Cup 2 K2,让飞奔的红鬃马如虎添翼。
关键词 高性能轮胎 日内瓦车展 动态 商业 米其林 法拉利 供应商 CUP
“Made in China”——A Hit at the FIFA World Cup 预览
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作者 Tao Wu 《中国对外贸易:英文版》 2018年第4期40-42,共3页
The World Cup,known as the“peace time wars”in China,is the world’s largest sports event and the sports IP with the greatest commercial value.The 2018 Russian World Cup kicked off on June 14th,with 32 teams competin... The World Cup,known as the“peace time wars”in China,is the world’s largest sports event and the sports IP with the greatest commercial value.The 2018 Russian World Cup kicked off on June 14th,with 32 teams competing for the FIFA World Cup.As the world’s most influential sports event,the World Cup is of great commercial value.At present,a complete World Cup profit system has been formed,ranging from broadcasting and sponsorship fees to a bottle of beer and a mascot and all becoming the drivers of the World Cup economy. 展开更多
关键词 World the CUP COMPLETE world with TIME MOST
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淋漓尽致 漂移练习场见闻VOL.1
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作者 魏铼 JK视觉摄 《汽车之友》 2018年第4期104-109,共6页
长久以来,漂移这项汽车运动一直是人们十分热衷的项目,D1GP、Formula D这两项著名赛事就不必多说了,FIA也把这项汽车运动单独划分为一项赛事,也就是FIA International Drift Cup。
关键词 漂移 练习 汽车运动 DRIFT FIA CUP
高炉加压水冷齿轮箱新技术及应用 预览
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作者 于成忠 张荣军 徐宝军 《鞍钢技术》 CAS 2018年第3期49-52,65共5页
介绍了高炉加压水冷齿轮箱的结构和原理以及在鞍钢高炉的应用,并对加压水冷齿轮箱和传统水冷齿轮箱进行了比较分析。结果表明,加压水冷齿轮箱能够有效节约氮气消耗,延长高炉定修周期间隔,减少维修工作量,有很好的推广价值。
关键词 高炉 加压水冷传动齿轮箱 S-杯 水冷站
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斗牛
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作者 ANTONY INGRAM ASTON PARROTT(摄影) 张弛(译) 《汽车与运动》 2018年第7期90-95,共6页
标致运动部门的标致208 GTi是目前热门的超级迷你小钢炮候选人,但它将如何抵挡雷诺Sport Clio 200 Cup这个细分车型的历史上最伟大的一员?
关键词 SPORT 候选人 GTI CUP 标致 雷诺
天然气管道清管器自激振动模型及影响规律
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作者 李华 王珂 +1 位作者 王东 廖柯熹 《油气储运》 北大核心 2018年第10期1163-1169,共7页
在清管器前端所聚集的杂质和管道内壁摩擦力的共同作用下,清管器皮碗会发生较大振动,甚至发生变形,从而降低清管作业的有效性。基于LuGre模型和Stribeck曲线,描述了清管器皮碗与管道内壁间摩擦力的非线性变化规律,通过合理约束清管器皮... 在清管器前端所聚集的杂质和管道内壁摩擦力的共同作用下,清管器皮碗会发生较大振动,甚至发生变形,从而降低清管作业的有效性。基于LuGre模型和Stribeck曲线,描述了清管器皮碗与管道内壁间摩擦力的非线性变化规律,通过合理约束清管器皮碗径向的自由度,建立了由集中质量弹性微元体表征的清管器自激振动模型。采用Matlab仿真软件,对DN200管道皮碗清管器不同工况下的自激振动规律进行分析,结果表明:随着过盈量增加,皮碗清管器的振幅随之增加;随着运行速度增加,皮碗清管器振幅先增加后降低。建立的天然气管道清管器自激振动模型,为合理选择皮碗清管器过盈量和清管运行速度提供了依据,可有效提高天然气管道清管作业的安全性与有效性。 展开更多
关键词 天然气管道 清管器 皮碗 自激振动 LUGRE模型 STRIBECK曲线
赛车总动员 预览
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作者 小飞蛾 《阅读》 2018年第7期52-59,共8页
赛车总动员1:“闪电”迷途遇导师 汽车世界,一年一度的“活塞杯大赛”(Piston Cup Racing)再次拉开序幕,麦昆McQueen是冠军最有力的竞争者。信心满满的他早早启程,不料却在参赛途中意外迷路,闯入了与世隔绝的油车水镇(Radiator... 赛车总动员1:“闪电”迷途遇导师 汽车世界,一年一度的“活塞杯大赛”(Piston Cup Racing)再次拉开序幕,麦昆McQueen是冠军最有力的竞争者。信心满满的他早早启程,不料却在参赛途中意外迷路,闯入了与世隔绝的油车水镇(Radiator Springs)。 展开更多
关键词 赛车 CUP 竞争者 汽车
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路特斯Exige Cup 430 Type 49/79
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《车迷》 2018年第9期10-11,共2页
路特斯在古德伍德速度节上公布了两辆纪念车款Exige Cup 430 Type 49和Exige Cup 430Type79,为了纪念路特斯在70年的品牌历史上最具标志性的赛车。这两辆车为Lotus Exclusive手工打造,是以Exige Cup 430为基础,并采用了Type49和79的配... 路特斯在古德伍德速度节上公布了两辆纪念车款Exige Cup 430 Type 49和Exige Cup 430Type79,为了纪念路特斯在70年的品牌历史上最具标志性的赛车。这两辆车为Lotus Exclusive手工打造,是以Exige Cup 430为基础,并采用了Type49和79的配色。其中Exige Cup 430 Type 49还参加了古德伍德速度节的超跑计时赛。 展开更多
关键词 古德伍德 公路车 Exige CUP 430 TYPE 49/79 空气动力学
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