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分析力的变化,研究运动规律
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作者 祝兴龙 《数理化解题研究(高中版)》 2017年第8期71-72,共2页
正确的分析物体的运动过程是高中学生必须具备的基本能力,对物体运动规律的研究可以提高学生分析问题、理论联系实际的能力.通过对运动物体的受力情况进行分析,可以很好的研究物体的运动规律.
关键词 力的变化 力的大小 力的方向
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大国地位变化的启示
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作者 李长久 《外向经济》 1995年第9期11-11,共1页
第二次世界大战结束50年来,大规模的军备竞赛和对抗,拖垮了原苏联、消弱了美国,战败国日本和德国却抓住机遇,集中人力、财力恢复和振兴经济,分别成为世界第二和第三经济大国。大国地位和实力的变化,提供了三点重要启示:
关键词 大国地位 原苏联 重要启示 军费开支 军备竟赛 二战后 竟争 战败国 力的变化 经济大国
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游泳
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《体育科技文献通报》 2004年第7期46-46,共1页
G861.102着装泳练习对提高自救与救生能力的实验研究=Experiment research on advancing the ability toself-saving and life saving through the exercisesof swimming wearing clothing[刊,中,A]/朱笛,邢荣颖(天津体育学院)//天... G861.102着装泳练习对提高自救与救生能力的实验研究=Experiment research on advancing the ability toself-saving and life saving through the exercisesof swimming wearing clothing[刊,中,A]/朱笛,邢荣颖(天津体育学院)//天津体育学院学报.-2004,19(1).-92-93表8参4(SJ) 展开更多
关键词 血乳酸 游泳运动员 实验研究 体育学院学报 北京体育大学学报 体育运动学校 负荷后 心率指标 力的变化 最大强度
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捞起月亮(散文)
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作者 陈如德 《山东教育》 1995年第3期43-43,共1页
井底捞月亮大概是妇孺皆知的最有趣的故事吧!月亮没捞到,那群活泼而怀着诚意的猴子却引起众人的喜爱。我虽然属相是猴,却自认比那群小猴高明,因为我果真从井底捞出了月亮。这井,一座是农田里的土井,一座是深在千尺的矿井;捞起的月亮,... 井底捞月亮大概是妇孺皆知的最有趣的故事吧!月亮没捞到,那群活泼而怀着诚意的猴子却引起众人的喜爱。我虽然属相是猴,却自认比那群小猴高明,因为我果真从井底捞出了月亮。这井,一座是农田里的土井,一座是深在千尺的矿井;捞起的月亮,则是曾被我救助而其事业至今仍在飞彩凝晖的我的二、三位老师。 文革初期有一年秋后大旱,小麦不能播种,这可急坏了农场的书记杨老头。我们学校农场有500亩土地, 展开更多
关键词 散文 抽水机 电雷管 小麦 幸免于难 力的变化 女学员 工班长 采煤面 大塌方
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TP200伺服无级定位气缸
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《机电新产品导报》 1994年第Z1期113-113,共1页
IP200伺服无级定位气缸是气缸活塞杆行程可进行无级伺服控制的气缸,其行程随控制信号压力的变化而呈线性变化输出。即给定一气压信号,气缸活塞杆就能停顿在相应的位置上,根据给定的气压信号变化程度能实现行程范围内任何一段动作的进、... IP200伺服无级定位气缸是气缸活塞杆行程可进行无级伺服控制的气缸,其行程随控制信号压力的变化而呈线性变化输出。即给定一气压信号,气缸活塞杆就能停顿在相应的位置上,根据给定的气压信号变化程度能实现行程范围内任何一段动作的进、退和停顿三种气缸杆运动状态。 展开更多
关键词 气压信号 伺服控制 气缸 无级 运动状态 控制信号 杆行程 力的变化 变化程度 调节灵敏度
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老年人牙齿为何怕冷怕热
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作者 魏开敏 《家庭医学(上半月)》 2001年第1期16-16,共1页
人到老年吃起东西来好像“挑肥拣瘦”似的,冷的吃不成,热的也不行,酸的、甜的都受不了,只好每顿吃些味淡的、不冷不热的半流食或流食,这是怎么回事? 原来,人到老年时牙釉质的渗透性降低,水分和有机成分相应减少,脆性增加;而温度及压力... 人到老年吃起东西来好像“挑肥拣瘦”似的,冷的吃不成,热的也不行,酸的、甜的都受不了,只好每顿吃些味淡的、不冷不热的半流食或流食,这是怎么回事? 原来,人到老年时牙釉质的渗透性降低,水分和有机成分相应减少,脆性增加;而温度及压力的变化,均可引起釉质的破坏。加之口腔内咀嚼过程中的长期机械磨损作用,使牙齿的咬(牙合)面慢慢磨损,牙本质外露,引起牙本质过敏。结果是对冷、热、酸、甜的刺激都十分敏感,无法保证正常饮食的摄入,只好挑挑拣拣。 展开更多
关键词 牙本质过敏 牙釉质 老年人 渗透性 机械磨损 力的变化 人牙 有机成分 牙齿疾病 口腔卫生
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基于真实情景下的九年级复习课教学实践研究——以《杠杆》复习课教学为例
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作者 贾晓斌 《中国科技期刊数据库 科研》 2022年第5期35-38,共4页
杠杆一直是中考的必考点,近年来虽然对杠杆知识的考察难度不断降低,但灵活性越来越高,面对灵活多变的新情境,学生们由于缺少生活体验,很难从新情境中抽离出杠杆模型,分析杠杆中力的变化问题,也很难对复杂情境进行受力分析,本文以初中“... 杠杆一直是中考的必考点,近年来虽然对杠杆知识的考察难度不断降低,但灵活性越来越高,面对灵活多变的新情境,学生们由于缺少生活体验,很难从新情境中抽离出杠杆模型,分析杠杆中力的变化问题,也很难对复杂情境进行受力分析,本文以初中“杠杆复习课”教学为例,借助生活中常见的“扁担”模型进行实践探究,从真实情境中掌握支点的选取,学会分析力的变化问题并且形成解题策略,通过实验突破复杂情境中的受力分析。 展开更多
关键词 扁担 支点 杠杆平衡条件 分析 力的变化
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Dietary advanced glycation end-products aggravate non-alcoholic fatty liver disease 被引量:7
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作者 Christopher Leung Chandana B Herath +7 位作者 Zhiyuan Jia Sof Andrikopoulos Bronwyn E Brown Michael J Davies Leni R Rivera John B Furness Josephine M Forbes Peter W Angus 《World Journal of Gastroenterology》 SCIE CAS 2016年第35期8026-8040,共15页
AIM To determine if manipulation of dietary advanced glycation end product(AGE), intake affects nonalcoholic fatty liver disease(NAFLD) progression and whether these effects are mediated via RAGE. METHODS Male C57Bl6 ... AIM To determine if manipulation of dietary advanced glycation end product(AGE), intake affects nonalcoholic fatty liver disease(NAFLD) progression and whether these effects are mediated via RAGE. METHODS Male C57Bl6 mice were fed a high fat, high fructose, high cholesterol(HFHC) diet for 33 wk and compared with animals on normal chow. A third group were given a HFHC diet that was high in AGEs. Another group was given a HFHC diet that was marinated in vinegar to prevent the formation of AGEs. In a second experiment, RAGE KO animals were fed a HFHC diet or a high AGE HFHC diet and compared with wildtype controls. Hepatic biochemistry, histology, picrosirius red morphometry and hepatic mR NA were determined. RESULTS Long-term consumption of the HFHC diet generated significant steatohepatitis and fibrosis after 33 wk. In this model, hepatic 4-hydroxynonenal content(a marker of chronic oxidative stress), hepatocyte ballooning, picrosirius red staining, α-smooth muscle actin and collagen type 1A gene expression were all significantly increased. Increasing the AGE content of the HFHC diet by baking further increased these markers of liver damage, but this was abrogated by pre-marination in acetic acid. In response to the HFHC diet, RAGE-/-animals developed NASH of similar severity to RAGE+/+ animals but were protected from the additional harmful effects of the high AGE containing diet. Studies in isolated Kupffer cells showed that AGEs increase cell proliferation and oxidative stress, providing a likely mechanism through which these compounds contribute to liver injury. CONCLUSION In the HFHC model of NAFLD, manipulation of dietary AGEs modulates liver injury, inflammation, and liver fibrosis via a RAGE dependent pathway. This suggests that pharmacological and dietary strategies targeting the AGE/RAGE pathway could slow the progression of NAFLD. 展开更多
关键词 Advanced glycation end-products FRUCTOSE STEATOHEPATITIS Non-alcoholic fatty liver disease Hepatic fibrosis Oxidative stress
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Hydrodynamics of three-phase fluidization of homogeneous ternary mixture in a conical conduit-Experimental and statistical analysis
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作者 R.K.Padhi D.T.K.Dora +2 位作者 Y.K.Mohanty G.K.Roy B.Sarangi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第10期1335-1343,共9页
Hydrodynamics of conical fluidized bed differ from that of columnar beds by the fact that a velocity gradient exists along the axial direction of the bed.The gas–liquid–solid fluidized bed has emerged in recent year... Hydrodynamics of conical fluidized bed differ from that of columnar beds by the fact that a velocity gradient exists along the axial direction of the bed.The gas–liquid–solid fluidized bed has emerged in recent years as one of the most promising devices for three-phase operations.Such a device is of considerable industrial importance as evident from its wide applications in chemical,refining,petrochemical,biochemical processing,pharmaceutical and food industries.To explore this,a series of experiments have been carried out for homogeneous well-mixed ternary mixtures of dolomite of varying compositions in a three-phase conical fluidized bed.The hydrodynamic characteristics determined included the bed pressure drop,bed fluctuation and bed expansion ratios.The single and combined effects of operating parameters such as superficial gas velocity,superficial liquid velocity,initial static bed height,average particle size and cone angle on the responses have been analyzed using response surface methodology(RSM).A 25 full factorial central composite experimental design has been employed.Analysis of variance(ANOVA) showed a high coefficient of determination value and satisfactory prediction second-order regression models have been derived.Experimental values of bed pressure drop,bed fluctuation and bed expansion ratios have been found to agree well with the developed correlations. 展开更多
关键词 Gas-liquid-solid fluidization Conical bed Bed pressure drop Bed fluctuation ratio and bed expansion ratio ANOVA
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两用竿和定位竿的使用方法
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作者 谭佛航 《中国钓鱼》 1998年第4期24-24,共1页
关键词 使用方法 钓竿 绕线轮 钓线 操作方法 定位方式 长度选择 固定长度 过线 力的变化
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