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生物绒与羽绒服用性能对比分析 预览
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作者 王丽莎 冯爱芬 《棉纺织技术》 CAS 北大核心 2019年第2期28-31,共4页
比较生物绒与羽绒的性能差异。观察了生物绒和羽绒的外观形态结构;测试了生物绒和羽绒的保暖性能和压缩性能。结果表明:30cm×30cm生物绒和羽绒的填充量相同时,生物绒的保暖性低于羽绒;生物绒填充量达到27g时的保暖效果等同于填充量... 比较生物绒与羽绒的性能差异。观察了生物绒和羽绒的外观形态结构;测试了生物绒和羽绒的保暖性能和压缩性能。结果表明:30cm×30cm生物绒和羽绒的填充量相同时,生物绒的保暖性低于羽绒;生物绒填充量达到27g时的保暖效果等同于填充量为18g羽绒的保暖效果;生物绒相对于羽绒更容易被压缩变形;生物绒和羽绒都具有优异的蓬松度;生物绒的弹性回复性能要低于羽绒。认为:生物绒是较好的保暖材料,羽绒的各项性能仍优于生物绒。 展开更多
关键词 生物绒 羽绒 保暖性 压缩性 对比分析
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Contactless Microwave Detection of Shubnikov–De Haas Oscillations in Three-Dimensional Dirac Semimetal ZrTe5
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作者 武敏 张红伟 +7 位作者 朱相德 陆建伟 郑国林 高文帅 韩玉岩 周建辉 宁伟 田明亮 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第6期49-52,共4页
We report Shubnikov–de Haas(SdH)oscillations of a three-dimensional(3D) Dirac semimetal candidate of layered material ZrTe5 single crystals through contactless electron spin resonance(ESR)measurements with the magnet... We report Shubnikov–de Haas(SdH)oscillations of a three-dimensional(3D) Dirac semimetal candidate of layered material ZrTe5 single crystals through contactless electron spin resonance(ESR)measurements with the magnetic field up to 1.4 T.The ESR signals manifest remarkably anisotropic characteristics with respect to the direction of the magnetic field,indicating an anisotropic Fermi surface in ZrTe5.Further experiments demonstrate that the ZrTe5 single crystals have the signature of massless Dirac fermions with nontrivialBerry phase,key evidence for 3D Dirac/Weyl fermions.Moreover,the onset of quantum oscillation of our ZrTe5 crystals revealed by the ESR can be derived down to 0.2 T,much smaller than the onset of SdH oscillation determined by conventional magnetoresistance measurements.Therefore,ESR measurement is a powerful tool to study the topologically nontrivial electronic structure in Dirac/Weyl semimetals and other topological materials with low bulk carrier density. 展开更多
关键词 DIRAC MICROWAVE Haas ESR SPIN down tool our
High-Q, low-mode-volume microsphere-integrated Fabry–Perot cavity for optofluidic lasing applications
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作者 XIAOQIN Wu YIPEI WANG +4 位作者 QIUSHU CHEN YU-CHENG CHEN XUZHOU LI LIMIN TONG XUDONG FAN 《光子学研究:英文版》 CSCD 2019年第1期50-60,共11页
We develop a hybrid optofluidic microcavity by placing a microsphere with a diameter ranging from 1 to 4 μm in liquid-filled plano-plano Fabry–Perot(FP) cavities, which can provide an extremely low effective mode vo... We develop a hybrid optofluidic microcavity by placing a microsphere with a diameter ranging from 1 to 4 μm in liquid-filled plano-plano Fabry–Perot(FP) cavities, which can provide an extremely low effective mode volume down to 0.3–5.1 μm^3 while maintaining a high Q-factor up to 1 × 10^4–5 × 10^4 and a finesse of ~2000. Compared to the pure plano-plano FP cavities that are known to suffer from the lack of mode confinement, diffraction, and geometrical walk-off losses as well as being highly susceptible to mirror misalignment, our microsphere-integrated FP(MIFP) cavities show strong optical confinement in the lateral direction with a tight mode radius of only 0.4–0.9 μm and high tolerance to mirror misalignment as large as 2°. With the microsphere serving as a waveguide, the MIFP is advantageous over a fiber-sandwiched FP cavity due to the open-cavity design for analytes/liquids to interact strongly with the resonant mode, the ease of assembly, and the possibility to replace the microsphere. In this work, the main characteristics of the MIFP, including Q-factor, finesse, effective mode radius and volume, and their dependence on the surrounding medium’s refractive index, mirror spacing, microsphere position inside the FP cavity, and mirror misalignment, are systematically investigated using a finite-element method.Then, by inserting dye-doped polystyrene microspheres of various sizes into the FP cavity filled with water, we experimentally realize single-mode MIFP optofluidic lasers that have a lasing threshold as low as a few microjoules per square millimeter and a lasing spot radius of only ~0.5 μm. Our results suggest that the MIFP cavities provide a promising technology platform for novel photonic devices and biological/chemical detection with ultra-small detection volumes. 展开更多
关键词 mirror radius diameter optical devices down EASE spot
An Up and Down Journey
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作者 Zhao Wei 《北京周报:英文版》 2019年第27期34-35,共2页
It’s a long and bumpy road for Chinese companies hoping to invest in the U.S. Increasing protectionist policies by the U.S. have resulted in a trade war with and declining investments from China, with the latter’s n... It’s a long and bumpy road for Chinese companies hoping to invest in the U.S. Increasing protectionist policies by the U.S. have resulted in a trade war with and declining investments from China, with the latter’s new foreign direct investment(FDI) in the U.S. 展开更多
关键词 FDI AN Up and DOWN JOURNEY
Chang’e-4 Probe Soft-Lands on Moon’s Far Side 预览
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《今日中国:英文版》 2019年第2期6-7,共2页
China’s Chang’e-4 probe touched down on the far side of the moon on January 3,the first spacecraft soft-landing on the moon’s uncharted side never visible from Earth.The probe,comprising a lander and a rover,landed... China’s Chang’e-4 probe touched down on the far side of the moon on January 3,the first spacecraft soft-landing on the moon’s uncharted side never visible from Earth.The probe,comprising a lander and a rover,landed at the preselected landing area at 177.6 degrees east longitude and 45.5 degrees south latitude on the far side of the moon at 10:26 a.m.Beijing time,the China National Space Administration announced.The far side of the moon has never been closely observed before.Therefore,getting first-hand information about the terrain and lunar soil components,as well as other scientific data,will help enrich human understanding of the moon. 展开更多
关键词 FAR LATITUDE FAR down east HELP HAS
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电子汽车衡“落架”后如何修复 预览
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作者 董光军 史光明 《衡器》 2019年第4期40-42,共3页
本文介绍了电子汽车衡'落架'的原因、修复以及对预防'落架'进行了叙述,望对汽车衡专业维修人员或汽车衡使用单位有一定的帮助。
关键词 电子汽车衡“落架” 原因 修复 预防
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是bore down upon还是bear down upon? 预览
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作者 侯松山 《江苏外语教学研究》 2019年第1期72-73,96共3页
授课过程中发现,学生很难理解第2版的《新世纪大学英语阅读教程(第1册)》第7单元课文《追求完美》中的一句原文:“The hot Kerala sun bores down upon it and dries it in half-an-hour or so.”结合四个运用实例,通过语法和逻辑分析,... 授课过程中发现,学生很难理解第2版的《新世纪大学英语阅读教程(第1册)》第7单元课文《追求完美》中的一句原文:“The hot Kerala sun bores down upon it and dries it in half-an-hour or so.”结合四个运用实例,通过语法和逻辑分析,文章指出原文出现了一个用法错误,词组应该是“bears down upon”而不是“bores down upon”。文章建议编著者在修订教材时要大胆质疑并及时发现错误,同时为了方便学生掌握要注出该词组的正确意思。 展开更多
关键词 《阅读教程(第1册)》 语法 逻辑 BORE DOWN upon BEAR
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长效抗菌防螨防臭羽绒的研发
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作者 宋春常 沈守兵 仇兆波 《上海纺织科技》 北大核心 2019年第7期26-28,共3页
为解决羽绒易滋生细菌、产生臭味等问题,使其具有持久长效的抗菌防螨防臭功能,通过助剂筛选,开发了复配型抗菌剂A、B及增效剂,同时确定了复配型抗菌剂A、B与增效剂的同浴整理工艺,并建立了模拟高湿热条件下羽绒产生异味的评定标准。整... 为解决羽绒易滋生细菌、产生臭味等问题,使其具有持久长效的抗菌防螨防臭功能,通过助剂筛选,开发了复配型抗菌剂A、B及增效剂,同时确定了复配型抗菌剂A、B与增效剂的同浴整理工艺,并建立了模拟高湿热条件下羽绒产生异味的评定标准。整理后的羽绒,经水洗10次后对白色念珠菌的抑菌率达到75%,同时释放TVOC的种类和数量远低于普通羽绒,从而可有效防止羽绒在使用及储存过程中产生异味。 展开更多
关键词 羽绒 抗菌 防螨 防臭 整理工艺 抑菌率
实验条件对羽绒清洁度分析结果的影响 预览
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作者 黄洁 何惠燕 任敏 《纺织报告》 2019年第3期8-9,15共3页
羽绒清洁度是羽绒检验中的一项重要技术指标,本课题通过样品的差异性、混样次数、振荡次数、过滤的操作手法、振荡的器具、人员目光等分析羽绒清洁度指标的影响因素。
关键词 羽绒 清洁度 影响因素
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The Research on Treating Collapsible Loess by Down Whole Deep Compaction and Cement Fly-ash Gravel 预览
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作者 Tao Xue Shang Gao 《建筑与工程前沿研究(英文)》 2019年第1期8-11,共4页
The treatment of loess foundation is always difficult.The analysis of its advantages and mechanism of treating loess foundation by CFG,on the base of project geology,through construction example,we suggest the compoun... The treatment of loess foundation is always difficult.The analysis of its advantages and mechanism of treating loess foundation by CFG,on the base of project geology,through construction example,we suggest the compound plan by both DDC and CFG.The tests illustrates that the down hole deep compaction and cement-fly ash-gravel are effective foundation treatment method to eliminate the collapsibility of loess,increase the bearing capacity and improve the behavior of composite foundations. 展开更多
关键词 DOWN hole DEEP COMPACTION CEMENT fly ash-gravel Collapsible loess Bearing capacity
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Research progress of traditional Chinese medicine nursing for pelvic inflammatory disease sequelae 预览
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作者 Pei-Yao Li Wen-Wen Zhao +3 位作者 Chun-Hua Zhang Ling Wang Hui-Xin Ding Chun-Guang Yu 《TMR整合医学》 2019年第3期1-7,共7页
Pelvic inflammatory disease refers to a group of female genital tr act on infec tious disease, mainly including endometritis, tubal phlogistic, oviduct ovarian abscess, if not 廿mely tr eatment of the disease is easy ... Pelvic inflammatory disease refers to a group of female genital tr act on infec tious disease, mainly including endometritis, tubal phlogistic, oviduct ovarian abscess, if not 廿mely tr eatment of the disease is easy to become chr onic, now called pelvic inflammatory disease sequelae, clinical manifestations in chronic pelvic pain, recurrent pelvic inflammatory disease, affect women's physical and mental health. TCM nursing based on the basic theory of TCM, apply the overall view, the nursing method of syndrome differentiation, the traditional Chinese medicine nursing technique is widely used in the disease, such as traditional Chinese medicine enema, Chinese medicine external treatment, moxibustion, ear acupuncture point buries a seed, methods of modern nursing, has the characteristics of simple and cheap effect, can reduce the swelling fights, promoting blood circulation to remove blood stasis, relieve the pelvic congestion, promote drainage in abdominal and pelvic cavity and the absorption of bag piece, adjust the viscera function, obvious effect and has unique advantages, further prove the uniqueness of TCM nursing and safety, provide the basis for clinical treatment. 展开更多
关键词 SEQUELAE of PELVIC INFLAMMATORY disease DOWN syndrome TCM NURSING techniques Research progress
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Luteolin induces hippocampal neurogenesis in the Ts65Dn mouse model of Down syndrome 预览
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作者 Wen-Bo Zhou Zong-Ning Miao +4 位作者 Bin Zhang Wei Long Fang-Xiu Zheng Jing Kong Bin Yu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第4期613-620,共8页
Studies have shown that the natural flavonoid luteolin has neurotrophic activity.In this study,we investigated the effect of luteolin in a mouse model of Down syndrome.Ts65Dn mice,which are frequently used as a model ... Studies have shown that the natural flavonoid luteolin has neurotrophic activity.In this study,we investigated the effect of luteolin in a mouse model of Down syndrome.Ts65Dn mice,which are frequently used as a model of Down syndrome,were intraperitoneally injected with 10 mg/kg luteolin for 4 consecutive weeks starting at 12 weeks of age.The Morris water maze test was used to evaluate learning and memory abilities,and the novel object recognition test was used to assess recognition memory.Immunohistochemistry was performed for the neural stem cell marker nestin,the astrocyte marker glial fibrillary acidic protein,the immature neuron marker DCX,the mature neuron marker NeuN,and the cell proliferation marker Ki67 in the hippocampal dentate gyrus.Nissl staining was used to observe changes in morphology and to quantify cells in the dentate gyrus.Western blot assay was used to analyze the protein levels of brain-derived neurotrophic factor(BDNF)and phospho-extracellular signal-regulated kinase 1/2(p-ERK1/2)in the hippocampus.Luteolin improved learning and memory abilities as well as novel object recognition ability,and enhanced the proliferation of neurons in the hippocampal dentate gyrus.Furthermore,luteolin increased expression of nestin and glial fibrillary acidic protein,increased the number of DCX+neurons in the granular layer and NeuN+neurons in the subgranular region of the dentate gyrus,and increased the protein levels of BDNF and p-ERK1/2 in the hippocampus.Our findings show that luteolin improves behavioral performance and promotes hippocampal neurogenesis in Ts65Dn mice.Moreover,these effects might be associated with the activation of the BDNF/ERK1/2 pathway. 展开更多
关键词 nerve REGENERATION LUTEOLIN HIPPOCAMPUS Ts65Dn mice NEUROGENESIS ERK BDNF NESTIN GFAP NEUN Down syndrome neural REGENERATION
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中考英语语篇及作文专项训练(一) 预览
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《中学生英语》 2018年第11期32-36,46共6页
一、完形填空阅读短文,掌握其大意,从每题所给的A、B、C三个选项中选择最佳答案填空。 It was a cold windy winter day and I was walking home from work. My head pointed down against the 1 when I noticed an old lady. She was... 一、完形填空阅读短文,掌握其大意,从每题所给的A、B、C三个选项中选择最佳答案填空。 It was a cold windy winter day and I was walking home from work. My head pointed down against the 1 when I noticed an old lady. She was walking on the sidewalk in her house slippers(拖鞋)。 展开更多
关键词 专项训练 英语 中考 COLD HOUSE was HOME DOWN
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雾霾与绿色转型
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作者 范珊珊(文) 《能源》 2018年第11期178-180,共3页
5年前,在中国的一些大城市,雾霾开始成为人们每日谈论的话题,更是各大媒体追踪的报道热点。雾霾肆虐时,我每天起床第一件事,就是打开窗帘看看窗外的天空是灰色还是蓝色,然后通过手机APP查看PM2.5数值。如果看到雾霾预警,心情会立即down... 5年前,在中国的一些大城市,雾霾开始成为人们每日谈论的话题,更是各大媒体追踪的报道热点。雾霾肆虐时,我每天起床第一件事,就是打开窗帘看看窗外的天空是灰色还是蓝色,然后通过手机APP查看PM2.5数值。如果看到雾霾预警,心情会立即down到谷底,戴上闷得快要喘不上来气的过滤口罩,不情愿地走出一直开着空气净化器的家,开启一天的工作。 展开更多
关键词 绿色转型 PM2.5 空气净化器 DOWN 大城市 APP
Micronization and Nanoization of Active Pharmaceutical Ingredients 预览
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作者 Stefan Mende 《物理科学与应用:英文版》 2018年第3期1-9,共9页
More than 40%of newly discovered drugs have little or no water solubility which presents a serious challenge to the successful development and commercialization of new drugs in the pharmaceutical industry.Additionally... More than 40%of newly discovered drugs have little or no water solubility which presents a serious challenge to the successful development and commercialization of new drugs in the pharmaceutical industry.Additionally,more than 90%of drugs approved since 1995 have poor solubility,poor permeability,or both.Therefore,it may be necessary to increase the dose of a poorly soluble drug to obtain the required efficacy which can lead to more side effects and higher cost to the patient.Performance of drugs can be improved by decreasing the particle size and,at the same time,increasing specific surface area,dissolution rate and the bioavailability of the drug in the human body.The routes of administration are different and listed as 60%for oral,5%for pulmonary,5%for ocular,5%for topical and 25%for injectable,approximately.The injectable drugs are the most interesting ones for nanoization,because smaller particles will increase performance,and will be useful when using micro needles.In a typical manufacturing process of APIs(active pharmaceutical ingredients)top down processes like high pressure homogenization and wet bead milling are used as standard methods to decrease the particle sizes down to a fineness range of 10 to 500 nanometers. 展开更多
关键词 APIS top DOWN process MICRONIZATION BIOAVAILABILITY scale-up GMP REPRODUCIBILITY IQ OQ FAT
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重温经典:用micro:bit gamepad制作吃豆对战游戏
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作者 陈杰 《无线电》 2018年第6期75-76,共2页
分析游戏角色与规则 游戏角色:吃豆的虫子、被吃的豆子 游戏规则: 1通过手柄上的up、down、left、right按钮控制吃豆的角色移动。
关键词 对战游戏 BIT 制作 游戏角色 游戏规则 DOWN 按钮控制 手柄
羽绒制品质量安全风险因子分析
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作者 章双杰 葛庆联 +1 位作者 刘宏祥 张礼久 《中国家禽》 北大核心 2018年第7期41-45,共5页
通过对羽绒加工生产中原料采购、加工环节和污水处理的质量安全风险分析,比较国内不同羽绒标准的要求和差异,以及不同国家对羽绒品质要求的差异,提出相应的质量控制策略,为羽绒制品建立科学有效的全程控制系统,为羽绒加工业可持继发展... 通过对羽绒加工生产中原料采购、加工环节和污水处理的质量安全风险分析,比较国内不同羽绒标准的要求和差异,以及不同国家对羽绒品质要求的差异,提出相应的质量控制策略,为羽绒制品建立科学有效的全程控制系统,为羽绒加工业可持继发展提供理论参考。 展开更多
关键词 羽绒 羽毛 质量安全 风险因子
新目标英语八年级(上)重点、考点归纳总结 预览
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《中学生英语》 2018年第2期44-55,共12页
(1)作名词n.心智;头脑;决心◇例如:Amoment of fear went through my mind but I told myself to calm down since I was still alive.(片刻的恐惧穿过我的脑海,但我告诉自己要冷静下来,因为我还活着。)
关键词 归纳总结 英语 考点 DOWN was
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怎样创造一片森林——模拟形象、模拟行为与模拟创造本身 预览
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作者 陈凯 《中国信息技术教育》 2018年第21期23-25,共3页
想要一片森林?那就请认真想象一下吧工作学习累了,来一局电脑游戏调节一下如何?这里有一款名字叫Advent ure(冒险)的游戏,内容是在迷宫中寻找宝藏。小心,迷宫中还有不少危险的生物!听上去挺有意思。运行游戏,屏幕上显示了一段文字:YOU A... 想要一片森林?那就请认真想象一下吧工作学习累了,来一局电脑游戏调节一下如何?这里有一款名字叫Advent ure(冒险)的游戏,内容是在迷宫中寻找宝藏。小心,迷宫中还有不少危险的生物!听上去挺有意思。运行游戏,屏幕上显示了一段文字:YOU AR E S TAN DING AT THE END OF A ROAD BEFORE A SMALL BRICK BUILDING.AROUND YOU IS A FOREST.A SMALL STREAM FLOWS OUT OF THE BUILDING AND DOWN A GULLY.(你站在路的尽头,那里有一座小砖房。你周围是一片森林。一条小溪从建筑物中流出,涌入一条沟壑。) 展开更多
关键词 森林 模拟 形象 行为 电脑游戏 DOWN TAN 建筑物
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Wah Kwong’s heritage:moving steadily 预览
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作者 Wang sijia David Palmer 《中国船检》 2018年第7期104-106,共3页
Reporter:How to comprehend the current position of Wah Kwong in the Hong Kong shipping industry and the world shipping industry?David Palmer:WK has been a leading shipping company in Hong Kong since 1952 and a foundin... Reporter:How to comprehend the current position of Wah Kwong in the Hong Kong shipping industry and the world shipping industry?David Palmer:WK has been a leading shipping company in Hong Kong since 1952 and a founding member of HKSOA in 1957.WK was one of the first shipowners to build ships in Japan in the 1960’s and in China in the 1990’s.The Chao family has consistently taken a strong interest in the development of Hong Kong’s position as a major international shipping hub and our current Chairman,Sabrina Chao recently stepped down from her role as Chairman of HK Ship Owners Association,continuing he father’s active engagement with the HK government to effect the promotion of HK as an international maritime centre. 展开更多
关键词 STRONG world BUILD Japan DOWN HAS HER was
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