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Changes in the population structure of Calanus sinicus during summer–autumn in the southern Yellow Sea 预览
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作者 Yongqiang Shi Song Sun +3 位作者 Chaolun Li Guangtao Zhang Bo Yang Peng Ji 《海洋学报:英文版》 SCIE CAS CSCD 2019年第8期56-63,共8页
Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food we... Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year. 展开更多
关键词 CALANUS SINICUS stage COMPOSITION SEX COMPOSITION population structure YELLOW Sea Cold Water Mass life history strategy
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连续种植不同绿肥作物耕层的土壤团聚体特征 预览 被引量:1
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作者 张钦 于恩江 +5 位作者 林海波 张爱华 陈正刚 朱青 曹卫东 朱大雁 《西南农业学报》 CSCD 北大核心 2019年第1期148-153,共6页
【目的】为探明连续种植绿肥对土壤团聚体的影响。【方法】以箭筈豌豆(Vicia sativa L.)、肥田萝卜(Raphanus sativus L.)、蓝花苕子(Vicia cracca L.)、毛叶苕子(Vicia villosa Roth)、光叶苕子(Vicia villosa var.)为对象,研究连续种... 【目的】为探明连续种植绿肥对土壤团聚体的影响。【方法】以箭筈豌豆(Vicia sativa L.)、肥田萝卜(Raphanus sativus L.)、蓝花苕子(Vicia cracca L.)、毛叶苕子(Vicia villosa Roth)、光叶苕子(Vicia villosa var.)为对象,研究连续种植不同绿肥对耕层土壤团聚体组成、直径的影响。【结果】连续种植光叶苕子主要提高 >5mm粒径的机械稳定性团聚体含量、2~0.25mm粒径的水稳性团聚体含量,肥田萝卜主要提高5~2mm粒径的机械稳定性团聚体含量、 >5mm粒径的水稳性团聚体含量,蓝花苕子和毛叶苕子主要提高2~0.25mm粒径的机械稳定性团聚体含量。 >5mm粒级的土壤水稳性团聚体增加有利于水稳性大团聚体的积累,其中肥田萝卜的土壤水稳性大团聚体含量最高。连续种植肥田萝卜、毛叶苕子有利于耕层土壤平均重量直径、几何平均直径的提升,而光叶苕子降低了土壤团聚体直径。土壤水稳性团聚体含量越高,土壤平均重量直径、几何平均直径越大,土壤结构的团聚度越高。【结论】连续种植绿肥能够提高不同粒径土壤机械稳定性、水稳性团聚体含量,有利于土壤水稳性大聚体( >0.25mm)的形成,对土壤团聚体直径的影响表现不同。 展开更多
关键词 土壤团聚体 绿肥 组成 直径 耕层
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Tourmaline geochemistry and boron isotopic variations as a guide to fluid evolution in the Qiman Tagh W-Sn belt,East Kunlun,China 预览
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作者 Zhen Zheng Yanjing Chen +3 位作者 Xiaohua Deng Suwei Yue Hongjin Chen Qingfei Wang 《地学前缘:英文版》 CAS CSCD 2019年第2期569-580,共12页
The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen,NW China,and is associated with early Paleozoic monzogranites,tourmaline is present throughout this belt.In this paper we report chemi... The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen,NW China,and is associated with early Paleozoic monzogranites,tourmaline is present throughout this belt.In this paper we report chemical and boron isotopic compositions of tourmaline from wall rocks,monzogranites,and quartz veins within the belt,for studying the evolution of ore-forming fluids.Tourmaline crystals hosted in the monzogranite and wall rocks belong to the alkali group,while those hosted in quartz veins belong to both the alkali and X-site vacancy groups.Tourmaline in the walk rocks lies within the schorledravite series and becomes increasingly schorlitic in the monzogranite and quartz veins.Detrital tourmaline in the wall rocks is commonly both optically and chemically zoned,with cores being enriched in Mg compared with the rims.In the Al-Fe-Mg and Ca-Fe-Mg diagrams,tourmaline from the wall rocks plots in the fields of Al-saturated and Ca-poor metapelite,and extends into the field of Li-poor granites,while those from the monzogranite and quartz veins lie within the field of Li-poor granites.Compositional substitution is best represented by the MgFe-1,Al(NaR)-1,and AlO(Fe(OH))-1 exchange vectors.A wider range of d11B values from-11.1‰to-7.1‰is observed in the wall-rock tourmaline crystals,the B isotopic values combining with elemental diagrams indicate a source of metasediments without marine evaporates for the wall rocks in the Qiman Tagh belt.Theδ11B values of monzogranite-hosted tourmaline range from-10.7‰and-9.2‰,corresponding to the continental crust sediments,and indicate a possible connection between the wall rocks and the monzogranite.The overlap inδ11B values between wall rocks and monzogranite implies that a transfer ofδ11B values by anataxis with little isotopic fractionation between tourmaline and melts.Tourmaline crystals from quartz veins haveδ11B values between-11.0‰and-9.6‰,combining with the elemental diagrams and geological features,thus indicating a common granite-derived source for t 展开更多
关键词 TOURMALINE Chemical composition BORON isotope Qiman Tagh W-Sn BELT Fluid evolution
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泌尿系结石患者的结石成分、疼痛特点及护理对策分析
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作者 刘红 苏云艳 张荣 《国际护理学杂志》 2019年第14期2164-2167,共4页
目的分析泌尿系结石患者的结石成分、疼痛特点及护理干预措施.方法选取2014年8月~2016年7月该院泌尿系结石伴疼痛患者450例随机分为对照组和观察组,各225例.两组患者均给予结石成分分析并给予基础护理,观察组在基础护理基础上给予全方... 目的分析泌尿系结石患者的结石成分、疼痛特点及护理干预措施.方法选取2014年8月~2016年7月该院泌尿系结石伴疼痛患者450例随机分为对照组和观察组,各225例.两组患者均给予结石成分分析并给予基础护理,观察组在基础护理基础上给予全方位护理干预,包括全面评估疼痛、病房环境、采用物理方法缓解疼痛、多饮水、根据结石成分分析结构给予相应饮食指导、心理干预等.统计泌尿系结石成分分析结果,并对比两组患者疼痛缓解时间分布特点.结果两组共450例患者中,经结石成分分析显示,370例属于含钙结石(82.22%),均含有草酸钙;290例为混合性结石(64.44%).观察组患者疼痛缓解时间<2h和2~6h的比例和对照组比较显著较高,疼痛缓解时间在6~12h和>12h的比例和对照组比较显著较低,差异均有统计学意义(均P<0.05).结论对泌尿系结石患者给予结石成分分析,并给予全方位有效的护理干预,可以明显缩短疼痛缓解时间,提高患者的生活质量. 展开更多
关键词 结石 成分 草酸钙 饮食 护理
建筑施工图设计中存在的主要问题研究 预览
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作者 周锬 《工程建设与设计》 2019年第17期295-296,299共3页
随着建筑行业的快速发展,对建筑施工图的设计质量要求也越来越高。建筑施工图作为现场建设的重要依据,只有具备完善的体系才能对施工进行有效指导,然而在建筑施工图设计过程中,仍存在一系列问题需要解决。论文阐述了建筑工程设计主要阶... 随着建筑行业的快速发展,对建筑施工图的设计质量要求也越来越高。建筑施工图作为现场建设的重要依据,只有具备完善的体系才能对施工进行有效指导,然而在建筑施工图设计过程中,仍存在一系列问题需要解决。论文阐述了建筑工程设计主要阶段及建筑施工图的主要构成,分析了建筑施工图设计中存在的主要问题,并提出相应的解决方法。 展开更多
关键词 建筑 施工图设计 构成 问题 解决方法
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Diabetes in the Kokan region of India 预览
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作者 Patil Suvarna Kadam Shruti +1 位作者 Desai Maruti Joglekar Charudatta 《世界糖尿病杂志:英文版(电子版)》 2019年第1期37-46,共10页
BACKGROUND BKL Walawalkar Hospital is situated near the village of Dervan in the Kokan region of the state of Maharashtra in India.A survey of 2200 surrounding villages showed 51.8%adults had body mass index(BMI)below... BACKGROUND BKL Walawalkar Hospital is situated near the village of Dervan in the Kokan region of the state of Maharashtra in India.A survey of 2200 surrounding villages showed 51.8%adults had body mass index(BMI)below<18.5 kg/m2 and only 4.5%were overweight.A survey of 11521 adolescent girls from rural schools showed 64%prevalence of thinness.In the same region,government survey reported the prevalence of diabetes around 7%,and 70%prevalence of leanness.This reinforced the fact that the overall population of Kokan is lean.Hence,we decided to investigate body composition of diabetic people from our hospital clinic by carrying out a clinic-based case control study.AIM To study body composition of diabetics in a rural clinic of Kokan.METHODS In a case-control study,168 type 2 diabetic patients(102 men)attending the outpatient department at a rural hospital and 144 non-diabetic controls(68 men)in the Chiplun area of the Kokan region were recruited.History of diabetes(age of onset,duration),anthropometric measurements(height,weight,waist and hip circumference)were recorded.Body composition was measured by bioimpedance using the TANITA analyzer.RESULTS More than 45%of diabetic subjects had a 1st degree family history of diabetes,and more than 50%had macrovascular complications.The average BMI in diabetic subjects was 24.3 kg/m2.According to World Health Organization standards,prevalence of underweight was 8%and that of normal BMI was around 50%.Underweight and normal diabetic subjects(men as well as women)had significantly lower body fat percentage,higher muscle mass percentage,lower visceral fat and lower basal metabolic rate when compared to their overweight counterparts.CONCLUSION The diabetic population in Kokan has near normal body composition,and BMI has considerable limitations in assessing body composition and it also lacks sensitivity for assessing risk for diabetes in this population.High prevalence of family history of diabetes may point towards genetic predisposition.Leanness is an inherent characteristic o 展开更多
关键词 BODY COMPOSITION DIABETES METABOLISM MALNUTRITION Kokan
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记忆·构成·行为的空间转译--基于二年级建筑设计教学实践与探索 预览
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作者 杨媛媛 冯超 《科技视界》 2019年第5期235-236,共2页
本文从记忆、构成、行为与空间的转译出发,阐述了二年级幼儿园课题的设计思路与理念,以启发学生逻辑思维、提高学生空间塑造能力根本点,立足于学生对事物的认知与体验而进行的启发式教学探索。
关键词 记忆 构成 行为 空间转译 建筑设计教学
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带式输送机防纵向撕裂保护系统研究 预览
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作者 王毅锋 《机电工程技术》 2019年第4期228-229,共2页
为有效防止煤矿带式输送机发生纵向撕裂事故,更好的保障带式输送机的安全、稳定运行,基于引发带式输送机纵向撕裂的原因,设计了一种带式输送机防纵向撕裂保护系统,具体介绍了该系统的主要组成,工作原理,检测预警原理以及可实现的主要功... 为有效防止煤矿带式输送机发生纵向撕裂事故,更好的保障带式输送机的安全、稳定运行,基于引发带式输送机纵向撕裂的原因,设计了一种带式输送机防纵向撕裂保护系统,具体介绍了该系统的主要组成,工作原理,检测预警原理以及可实现的主要功能,实际应用结果表明,应用该种带式输送机防纵向撕裂保护系统能有效防止带式输送机发生纵向撕裂,显著降低带式输送机运行成本,为企业创造更多经济效益。 展开更多
关键词 输送机 纵向撕裂原因 保护系统 组成 检测预警
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反刍动物生成VFA的研究进展 预览
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作者 王淑玲 王后福 +7 位作者 盖叶顶 矣国 李鹏飞 杨仁辉 周荣康 杨振 成潇 冷静 《中国草食动物科学》 CAS 2019年第5期46-49,共4页
反刍动物通过瘤胃降解饲料中的碳水化合物生成大量的挥发性脂肪酸(VFA)和气体(CO2,CH4),VFA的生成与动物所需的能量和营养关系紧密。瘤胃微生物对生成VFA有巨大影响,同时VFA的生成也影响着瘤胃发酵。文章通过对瘤胃中VFA的组成、生成途... 反刍动物通过瘤胃降解饲料中的碳水化合物生成大量的挥发性脂肪酸(VFA)和气体(CO2,CH4),VFA的生成与动物所需的能量和营养关系紧密。瘤胃微生物对生成VFA有巨大影响,同时VFA的生成也影响着瘤胃发酵。文章通过对瘤胃中VFA的组成、生成途径及其影响生成VFA的因素进行简要阐述,旨在为反刍动物生长发育及生产提供参考。 展开更多
关键词 反刍动物 瘤胃微生物 VFA 代谢 组成
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酚类对酒的风味影响及白酒酚类控制策略 预览
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作者 祝贺 杨涛 +5 位作者 郝哲兵 姚鹏 吴健 蓝彩红 刘盛钢 吴小霞 《食品工业科技》 CAS 北大核心 2019年第18期361-367,共7页
酚类物质是存在于大部分酒中的风味物质,对酒风味品质控制具有重要意义。酒体中的酚类物质组成及含量存在很大区别,本文对酒中酚类物质的来源、含量、化学组成对酒品质的影响及控制策略进行综述,为研究白酒酚类差异的产生原因及控制方... 酚类物质是存在于大部分酒中的风味物质,对酒风味品质控制具有重要意义。酒体中的酚类物质组成及含量存在很大区别,本文对酒中酚类物质的来源、含量、化学组成对酒品质的影响及控制策略进行综述,为研究白酒酚类差异的产生原因及控制方法提供思路。 展开更多
关键词 酚类 含量 组成 白酒风味品质
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Floristic composition and ecological gradient analyses of the Liakot Forests in the Kalam region of District Swat,Pakistan 预览
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作者 Sohail Anwar Shujaul Mulk Khan +2 位作者 Zeeshan Ahmad Zahid Ullah Majid Iqbal 《林业研究:英文版》 CAS CSCD 2019年第4期1407-1416,共10页
Kalam Kohistan is a dry,temperate hilly region in the Hindu Raj Series of the Greater Hindu Kush Mountains with diverse forests.As plant distribution and composition is expression of a range of various environmental v... Kalam Kohistan is a dry,temperate hilly region in the Hindu Raj Series of the Greater Hindu Kush Mountains with diverse forests.As plant distribution and composition is expression of a range of various environmental variables,ecological and floristic attributes of vegetation in the Laikot Forests were therefore evaluated via consecutive explorative trips.These forests have not been evaluated ecologically before due to harsh climatic conditions and issues of accessibility and the study in hand is one of the first in its nature.Quantitative ecological techniques were used to sample forest vegetation and identify species in quadrats of 2 m×2 m for herbs,5 m×5 m for shrubs and 10 m×10 m for trees.All the data of 195 plant species and environmental factors were analyzed via Two-way Cluster Analysis and Canonical Correspondence Analysis using PCORD and CANOCO software.Among 195 plant species from 63 families were 27 species of Asteraceae,the most-speciose family,followed by Poaceae(20 spp.).The dominant life form was therophyte(86 spp.;44%share),followed by phanerophyte(41 spp.;21%share).For the leaf size spectrum,most prevalent was nanophyll(73 spp.;44%)followed by microphyll(66 spp.,34%)and mesophyll(44 spp.;23%).Calcium carbonate,pH,potassium,sand,silt,organic matter,slope aspect and grazing significantly influenced species composition,distribution and habitat.The floristic variation in the region was diverse due to elevational and aspect gradients and thus devided into three zones.This vegetation zonation can be utilized for forest management,species and habitat conservation.Both in situ and ex situ conservation of threatened plant species may improve their conservation status in future if address properly. 展开更多
关键词 FLORISTIC composition Ecological factors Life FORM spectra Leaf FORM classes Elevation ZONES CANONICAL CORRESPONDENCE analysis(CCA)
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甘肃盐池湾国家级自然保护区昆虫类群组成、区系分布及其与植被类型关系研究 预览
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作者 张玉斌 张书瑜 王惠萍 《防护林科技》 2019年第9期19-22,共4页
为了查清甘肃盐池湾国家级自然保护区内昆虫种类组成及昆虫区系特征,采用实地踏查和样点调查相结合的方法,对样方内和踏查线路中出现的所有昆虫个体均采集标本并鉴定,统计昆虫种类,确定其目、科、属的区系地理成分。结果表明:分布于该... 为了查清甘肃盐池湾国家级自然保护区内昆虫种类组成及昆虫区系特征,采用实地踏查和样点调查相结合的方法,对样方内和踏查线路中出现的所有昆虫个体均采集标本并鉴定,统计昆虫种类,确定其目、科、属的区系地理成分。结果表明:分布于该保护区的昆虫有7目25科61属88种。保护区最多是鳞翅目、鞘翅目和直翅目昆虫,其科、属和种数分别占全部科、属和种数的28.00%、45.90%和44.31%,32.00%、21.31%和18.18%,12.00%、11.47%和19.32%,其他目的属数和种数占比都小于10%。 展开更多
关键词 盐池湾自然保护区 昆虫 组成 区系
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长白山天池火山千年大喷发2期空降浮岩对比 预览
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作者 王禹钦 于红梅 +2 位作者 许建东 陈正全 赵波 《地震地质》 EI CSCD 北大核心 2019年第1期208-224,共17页
长白山天池火山的喷发历史和喷出物层序一直以来是人们关注的焦点。目前,对于千年大喷发以来空降堆积物,尤其是灰白色空降浮岩层之上的粗面质杂色空降浮岩的地层划分仍具有较大争议。文中通过对野外地层的详细观察,对2层空降浮岩层进行... 长白山天池火山的喷发历史和喷出物层序一直以来是人们关注的焦点。目前,对于千年大喷发以来空降堆积物,尤其是灰白色空降浮岩层之上的粗面质杂色空降浮岩的地层划分仍具有较大争议。文中通过对野外地层的详细观察,对2层空降浮岩层进行对比研究,发现两者之间没有沉积间隔,认为2期空降浮岩均应划分为千年大喷发的喷发物。下部赤峰期灰白色空降浮岩成分较为均一,呈棱角状,正粒序,分选较好;上部圆池期喷发为脉动式喷发,岩性为富土黄色浮岩和富黑色浮岩颗粒互层,浮岩呈棱角状,粒序不明显,分选较好。2期浮岩粒度呈正态分布,在中值和分选系数图中均投点于空降堆积区内。浮岩内斑晶以长石和辉石为主,但圆池期黑色浮岩内斑晶含量略高。赤峰期空降浮岩为灰白色碱流质,气孔较大,连续贯通,气孔壁薄。圆池期土黄色空降浮岩为粗面质,气孔连通,气孔壁略厚;黑色浮岩颗粒成分虽然也投点为粗面质,但Si O2含量明显较低,气孔度低,气孔壁厚。圆池期喷发强度较赤峰期喷发强度弱。多种岩浆成分说明长白山天池火山下具有复杂的岩浆系统,多种岩浆可能以分层的形式存在,赤峰期仅喷出了上部的碱流岩,圆池期的脉动式喷发喷出了不同层位的岩浆。 展开更多
关键词 空降浮岩 粒度 气孔结构 成分 千年大喷发 天池火山
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Research Progress on the Intervening Effects of Active Components of Chinese Herbs on Amyloid-Beta-lnduced Injury of Neural Cells
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作者 Hang-Xuan Wu Er-Wei Hao +6 位作者 Zheng-Cai Du Jian-Feng Qin Wei Wei Xiang-Long Pan Jin-Ling Xie Xiao-Tao Hou Jia-Gang Deng 《世界中医药杂志:英文版》 2019年第2期122-130,共9页
Alzheimer's disease is a common clinical central nervous system degenerative disease. From 1906, it has not yet been clearly revealed the pathogenesis, and there are no clinically safe and effective drugs. Amyloid... Alzheimer's disease is a common clinical central nervous system degenerative disease. From 1906, it has not yet been clearly revealed the pathogenesis, and there are no clinically safe and effective drugs. Amyloid-beta (Aβ) cascade reaction theory is currently recognized as the pathogenesis. Aβ deposition of neurotoxicity is an important part of the pathogenesis. There are Aβ-induced inflammation of the central nervous and oxidative stress-induced apoptosis induced by a variety of ways leading to neuronal dysfunction and death. This article summarizes the active ingredients of traditional Chinese medicine that has a protective effect on Aβ toxicity in recent years. Traditional Chinese medicine mainly through the antiapoptosis, antioxidation, and anti-inflammatory reduces Aβ production and deposition of Aβ on the protection of nerve cell injury. 展开更多
关键词 Alzheimer's disease amyloid-beta CASCADE reaction monomer composition traditional Chinese medicine β-amyloid
SiO2/HCNFs双相纳米填料的制备与表征
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作者 王璐 金永中 +3 位作者 陈建 李兵红 龚勇 蒋春 《炭素技术》 CAS 北大核心 2019年第1期10-13,共4页
使用原位接枝法在螺旋纳米炭纤维表面接枝纳米二氧化硅粒子,制备补强性能良好的SiO2/HCNFs双相纳米填料。利用TEM、SEM、FT-IR对样品的形貌和组成进行了表征,重点探讨了接枝反应温度对SiO2/HCNFs双相填料形貌和结合胶含量的影响。结果表... 使用原位接枝法在螺旋纳米炭纤维表面接枝纳米二氧化硅粒子,制备补强性能良好的SiO2/HCNFs双相纳米填料。利用TEM、SEM、FT-IR对样品的形貌和组成进行了表征,重点探讨了接枝反应温度对SiO2/HCNFs双相填料形貌和结合胶含量的影响。结果表明,硝酸对螺旋纳米炭纤维有明显的截断作用,可降低纤维的长径比;接枝产物SiO2/HCNFs双相纳米填料形貌好,纤维表面的纳米SiO2粒子形貌较佳,分布均匀;SiO2/HCNFs双相纳米填料中SiO2粒子的量会随着反应温度的升高先增加后减小,其中当反应温度在80~90℃时,接枝效果最佳;当反应温度为90℃时,制备出的SiO2/HCNFs双相纳米填料的结合胶含量最高为30.5%,对天然橡胶的补强效果最好。 展开更多
关键词 SiO2/HCNFs双相纳米填料 原位接枝法 形貌 组成 结合胶
钛表面微弧氧化结构和成分对其润湿性的影响 预览
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作者 张贤琳 王晓琳 +5 位作者 马建威 李宝娥 李海鹏 刘世敏 梁春永 王洪水 《材料导报》 EI CAS CSCD 北大核心 2019年第24期4035-4039,共5页
通过改变微弧氧化过程中的电压及电流在钛表面分别制备了羟基磷灰石(HA)和TiO2涂层,为分析表面不同结构和成分对材料润湿性的影响,利用超声清洗制备了具有多孔结构的HA。结果表明:对于不同形貌的HA涂层,花瓣状结构HA的润湿性优于多孔结... 通过改变微弧氧化过程中的电压及电流在钛表面分别制备了羟基磷灰石(HA)和TiO2涂层,为分析表面不同结构和成分对材料润湿性的影响,利用超声清洗制备了具有多孔结构的HA。结果表明:对于不同形貌的HA涂层,花瓣状结构HA的润湿性优于多孔结构,且HA的花瓣越大、致密性越高,其润湿性越好;而与多孔结构的TiO2相比,HA涂层的接触角更小,润湿性更好。 展开更多
关键词 微弧氧化 结构 成分 润湿性
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Estimating areal carbon fixation of intertidal macroalgal community based on composition dynamics and laboratory measurements 预览
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作者 DU Guoying ZHAO Ezi +1 位作者 LIU Chunrong TANG Xianghai 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期93-101,共9页
The community dynamics and potential carbon fixation of intertidal macroalgae were investigated monthly from April 2014 to April 2015 in the northwest coast of Yellow Sea.Seasonal variations in biomass and carbon fixa... The community dynamics and potential carbon fixation of intertidal macroalgae were investigated monthly from April 2014 to April 2015 in the northwest coast of Yellow Sea.Seasonal variations in biomass and carbon fixation were presented and showed close relationship with community structure.The carbon fixation rate ranged from 0.48±0.13 mg C/(g FW·d)to 4.35±0.12 mg C/(g FW·d).Sargassum thunbergii,Chondrus ocellatus and Ulva intestinalis were three most infl uential species which contributed 27%,21.9%and 18.5%variation of carbon fixation rate,respectively.Standing carbon stocks ranged from 7.52 g C/m^2 to 41.31 g C/m^2,and estimated carbon stocks varied from 11.77 g C/m^2 to 96.49 g C/m^2.The larger difference between estimated and standing carbon stocks implied that more fixed carbon was exported from the community in summer and autumn than in winter.This study suggested that intertidal macroalgal community could provide a potential function in carbon fixation of coastal ecosystem. 展开更多
关键词 CARBON FIXATION CARBON STOCK community composition INTERTIDAL MACROALGAE Yellow Sea
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铝板带单机架热轧机的乳液适用性分析及应用 预览
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作者 张建辉 《有色金属加工》 CAS 2019年第2期31-33,共3页
文章对铝板带单机架热轧机的乳液适用性进行了详细分析;对所用乳液的组成、添加剂的种类及作用、乳液的配制以及乳液在使用过程中需要控制的性能指标进行了阐述,并举例说明了在实际轧制过程中出现的质量问题及解决方案。
关键词 铝板带单机架热轧机 乳液 配制 性能指标 应用
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A32高强船板钢生产工艺优化控制 预览
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作者 高云飞 高静 +3 位作者 王兵 王杨 戚翠芬 付菁媛 《山东冶金》 CAS 2019年第2期25-26,共2页
对高强船板A32生产数据进行统计分析,研究其性能富余量及性能与化学成分的关系。通过严格控制[C]、[Mn]含量,适当降低[Nb]含量,并优化优化控轧、控冷工艺参数,适当降低终轧温度和返红温度,保证了船板良好的力学性能,降低了船板生产成本。
关键词 高强船板 化学成分 性能 工艺
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伊朗岩沥青改性高模量沥青微观机理与性能分析 预览
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作者 王知乐 《新型建筑材料》 北大核心 2019年第2期80-84,共5页
采用荧光显微镜和化学组分试验对比分析了伊朗岩沥青改性高模量沥青的微观相态结构和化学组分;通过沥青三大性能指标测试、与集料黏附性和旋转薄膜加热试验,测试了伊朗岩沥青改性高模量沥青的路用性能。结果表明,较高加热温度下伊朗岩... 采用荧光显微镜和化学组分试验对比分析了伊朗岩沥青改性高模量沥青的微观相态结构和化学组分;通过沥青三大性能指标测试、与集料黏附性和旋转薄膜加热试验,测试了伊朗岩沥青改性高模量沥青的路用性能。结果表明,较高加热温度下伊朗岩沥青与基质沥青共混为相互交融的高模量沥青体系,且伊朗岩沥青改性高模量沥青中胶质和沥青质含量的增加保证了伊朗岩沥青改性高模量沥青具有优良的高温稳定性、与集料黏附性和抗老化性能,但其低温抗裂性能较差。采用伊朗岩沥青/SBS复合改性高模量沥青的方法不仅能改善其低温性能还能进一步提高其高温性能。 展开更多
关键词 伊朗岩沥青 高模量沥青 SBS 微观结构 组分 路用性能
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