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新型复合相变储能材料Na/Paraffin的制备与性能分析 被引量:2
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作者 徐永锋 李明 +3 位作者 罗熙 余琼粉 王云峰 冷从斌 《材料工程》 EI CAS CSCD 北大核心 2017年第11期66-71,共6页
为提升广泛应用于相变储能领域的石蜡的导热系数,在手套箱内将导热系数高、熔点低、密度小的金属Na与石蜡复合为Na/paraffin新型相变储能材料,并对其导热系数、相变潜热及储/放热特性进行研究。结果表明:5%Na/95%paraffin复合相变储能... 为提升广泛应用于相变储能领域的石蜡的导热系数,在手套箱内将导热系数高、熔点低、密度小的金属Na与石蜡复合为Na/paraffin新型相变储能材料,并对其导热系数、相变潜热及储/放热特性进行研究。结果表明:5%Na/95%paraffin复合相变储能材料导热系数较纯石蜡提高了17.6倍,储/放热速率均较纯石蜡提升了1倍;经过200次循环实验后,3%Na/97%paraffin复合相变储能材料相变温度由60.58℃下降到59.65℃,相变潜热由166.7520J·g^(-1)下降到160.5632J·g^(-1),热导率由2.33W·m^(-1)·K^(-1)减少到1.98W·m^(-1)·K^(-1)。 展开更多
关键词 na/paraffin 复合相变储能材料 相变潜热 导热系数
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The Paraffin Crystallization in Emulsified Waxy Crude Oil by Dissipative Particle Dynamics
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作者 Ruiqiong Wang Tiantian Du +1 位作者 Jinchen Cao Guoqiang Wang 《Frontiers in Heat and Mass Transfer》 EI 2024年第1期129-139,共11页
With the advancement of oilfield extraction technology,since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall,increasing the difficulty of crude oil extraction.In this paper,the mesosco... With the advancement of oilfield extraction technology,since oil-water emulsions in waxy crude oil are prone to be deposited on the pipe wall,increasing the difficulty of crude oil extraction.In this paper,the mesoscopic dissipative particle dynamics method is used to study themechanism of the crystallization and deposition adsorbed on thewall.The results show that in the absence of water molecules,the paraffin molecules near the substrate are deposited on themetallic surface with a horizontalmorphology,while the paraffin molecules close to the fluid side are arranged in a vertical column morphology.In the emulsified system,more water molecules will be absorbed on the metallic substrate than paraffin molecules,which obstructed the direct interaction between paraffin molecules and solid surface.Therefore,the addition of watermolecules hinders the crystallization of wax near the substrate.Perversely,on the fluid side,water molecules promote the formation of paraffin crystallization.The research in this paper reveals the crystallization mechanism of paraffin wax in oil-water emulsions in the pipeline from the microscopic scale,which provides theoretical support for improving the recovery of wax-containing crude oil and enhancing the transport efficiency. 展开更多
关键词 Emulsified waxy crude oil paraffin crystal DEPOSITION dissipative particle dynamics
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一种基于加权状态选择的LTE NAS协议模糊测试方法
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作者 廖显锋 吴礼发 《信息安全研究》 北大核心 2025年第1期12-20,共9页
NAS协议是LTE(long-term evolution)网络中移动设备与核心网络之间的主要控制面协议,其安全性对于保障整个4G网络稳健安全运行具有重要意义.模糊测试是一种广泛使用的漏洞挖掘技术,现有的模糊测试方法应用于NAS(non-access stratum)协... NAS协议是LTE(long-term evolution)网络中移动设备与核心网络之间的主要控制面协议,其安全性对于保障整个4G网络稳健安全运行具有重要意义.模糊测试是一种广泛使用的漏洞挖掘技术,现有的模糊测试方法应用于NAS(non-access stratum)协议时存在测试效率低、测试用例难以构建等问题.为了解决这些问题,提出了一种基于权重的测试状态选择算法:以NAS协议状态机为基础,根据测试反馈动态地调整每个测试状态的权重;以消息元素IE为最小单位设计了测试用例生成算法;实现了模糊测试工具NASFuzzer并对开源核心网open5GS及真实终端设备进行测试.测试结果表明,该方法能够有效挖掘LTE NAS协议实现中的漏洞. 展开更多
关键词 LTE naS 模糊测试 状态选择 漏洞挖掘
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短b-轴多级孔ZSM-5无Na^(+)合成及催化正庚烷裂解性能
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作者 钟少聪 赵德明 +4 位作者 史会兵 姜海英 王龙 刘纪昌 朱卡克 《石油学报(石油加工)》 北大核心 2025年第1期30-40,共11页
ZSM-5分子筛存在各向异性扩散传质,缩短b-轴长度和构筑多级孔是提升扩散性能的有效途径。发展了将共模板(四丙基氢氧化铵和四丁基氢氧化铵)与致孔剂(聚二烯丙基二甲基氯化铵)相结合的制备方法,在无Na^(+)体系中一步合成了短b-轴多级孔道... ZSM-5分子筛存在各向异性扩散传质,缩短b-轴长度和构筑多级孔是提升扩散性能的有效途径。发展了将共模板(四丙基氢氧化铵和四丁基氢氧化铵)与致孔剂(聚二烯丙基二甲基氯化铵)相结合的制备方法,在无Na^(+)体系中一步合成了短b-轴多级孔道ZSM-5分子筛。结合分子筛结构表征分析,探讨了短b-轴多级孔道ZSM-5分子筛制备过程中,铝源、致孔剂含量和硅/铝摩尔比对其形貌和结构的影响。经过P、La改性后,以正庚烷作为探针分子对其催化裂解性能进行评价。结果表明,短b-轴多级结构可以促进Haag-Dessau机理裂解反应,抑制双分子裂解和氢转移副反应。因此,短b-轴多级孔道ZSM-5分子筛显示出更高的催化活性、轻烯烃收率和选择性,以及更低的芳烃选择性。 展开更多
关键词 ZSM-5 短b-轴 na^(+)体系 轻烯烃 催化裂解
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Interaction between Mitomycin C and DNA at Paraffined Graphite Electrode
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作者 郭明 谭非 +1 位作者 胡润淮 俞庆森 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期199-203,共5页
Aim To investigate the electrochemical behaviors of Mitomycin C (MC) and its interaction with calf thymus DNA (ctDNA). Methods The cyclic vohammetry (CV) was carried out at a paraffined graphite electrode. Resul... Aim To investigate the electrochemical behaviors of Mitomycin C (MC) and its interaction with calf thymus DNA (ctDNA). Methods The cyclic vohammetry (CV) was carried out at a paraffined graphite electrode. Results MC showed a well-defined oxidation-reduction peak. As a result of reaction with ctDNA, the peak current of MC decreased apparently. According to corresponding electrochemical equations, the diffusion coefficient of both free and MC-DNA complex have been determined, and the heterogeneous rate constants were also obtained simultaneously. Conclusion The solid paraffined graphite electrode could be used to estimate parameters of the interaction between DNA and MC, and provide the convenient and sensitive analysis. 展开更多
关键词 mitomycin C calf thymus Dna cyclic voltammetry paraffined graphite electrode
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A Paraffin Sectioning Method Without Using the Microtome and an Analysis Method for Optical Information of the Plant Anatomical Digital Photographs
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作者 洪亚平 《Agricultural Science & Technology》 CAS 2010年第6期28-31,共4页
[Objective] The research aimed to study a paraffin method without using the microtome,and also introduced an analysis method for optical information of the plant anatomical digital photographs.[Method] The plant mater... [Objective] The research aimed to study a paraffin method without using the microtome,and also introduced an analysis method for optical information of the plant anatomical digital photographs.[Method] The plant material softened or not was embedded in paraffin according to the paraffin method.Cut the thin paraffin sections from the paraffin block with a sharp two-sided blade under anatomical lens.The thin material sections rolled up when they were cut off.Took the section rolls to a slide,and then heated them to melt the paraffin section roll.When the paraffin melted,the sections of plant material were rolled out.After the common or simplified procedures of staining and mounting,the preparations were finished.When an anatomical digital photograph was processed,copy it into the word file and two copies of the original photograph were obtained.One copy was selected to make it to be a negative photograph,and then press the key "Press Screen" to copy the screen frame.After it was copied into the word file,cut of the unnecessary parts and other operations were carried out,then processed photograph was obtained.[Results] The anatomical preparation for research was gotten.The analyzed digital photograph of the leaf structure of Salix matsudana var.matsudana f.tortuosa has some a three-dimensional effect,and the different leaf structures and cells,e.g.cuticle,cell wall,protoplast,vein,etc.can be identified easily.[Conclusion]The paraffin method without using the microtome has advantages of low cost and higher efficiency,which could be applied by the beginner or in the time without a microtome to be used.The analysis of the plant anatomical digital photographs can acquire more structural information than the original digital photographs,which shows the potentiality and prospects of the optical information analysis of the microscopic imagery and its digital photograph. 展开更多
关键词 paraffin method Digital photograph Optical information Analysis
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2022-2023年山东省A(H1N1)pdm09流感病毒HA、NA基因变异特征分析
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作者 吴巨龙 张淑 +4 位作者 何玉洁 孙林 宋绍霞 孙文魁 刘倜 《中国人兽共患病学报》 CAS CSCD 北大核心 2024年第5期471-477,共7页
目的 了解山东省2022-2023流感监测年度分离的A(H1N1)pdm09亚型流感病毒血凝素(hemagglutinin,HA)和神经氨酸酶(neuraminidase,NA)基因的变异特征,为流感的防控提供科学依据。方法 从流感监测网络实验室分离的流感毒株中按地市随机选取1... 目的 了解山东省2022-2023流感监测年度分离的A(H1N1)pdm09亚型流感病毒血凝素(hemagglutinin,HA)和神经氨酸酶(neuraminidase,NA)基因的变异特征,为流感的防控提供科学依据。方法 从流感监测网络实验室分离的流感毒株中按地市随机选取14株A(H1N1)pdm09亚型流感毒株,以WHO推荐的当季疫苗株为参考进行全基因组测序,并采用荧光法开展神经氨酸酶抑制(neuraminidase inhibition,NI)实验以评估药物敏感性。结果 山东省2022-2023年度分离的A(H1N1)pdm09流感病毒属于6B.1A分支中的5a.2a进化簇,核苷酸序列比对分析显示,HA和NA基因与2021-2023年度北半球疫苗株A/Victoria/2570/2019的亲缘关系较为接近,同源性分别为98.5%~98.7%和98.8%~99.1%。氨基酸序列分析显示,HA蛋白有20个位点发生了氨基酸序列变异,并发现1株病毒可能发生抗原漂移,有3株病毒发生了HA蛋白糖基化位点的缺失。NA酶相关重要位点未发生变异。NI实验显示,所测流感毒株均对抗流感病毒药物敏感。结论 所监测毒株与疫苗株整体同源性很高,但氨基酸存在一定程度变异,今后有必要持续开展流感病毒基因变异特征监测以了解流感流行的风险,以及评价基因变异对流感疫苗和治疗药物效果的影响。 展开更多
关键词 甲型H1N1pdm09流感 HA基因 na基因 基因变异
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围绕FFPE样本特性的DNA纯化纳米磁珠优化
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作者 肖林 吕晓芳 +4 位作者 曹师瑜 江丹 孙林雍 李坤 叶丰 《临床与实验病理学杂志》 CAS 北大核心 2024年第7期725-730,共6页
目的 探讨围绕福尔马林固定石蜡包埋(formalin fixed paraffin embedded, FFPE)样本特性获取更高质量/得率的纳米磁珠核酸提取方案,改进分子病理技术。方法 合成4大类15个小类的备选磁珠,以FFPE样本为中心,筛选高质量/得率磁珠。模拟常... 目的 探讨围绕福尔马林固定石蜡包埋(formalin fixed paraffin embedded, FFPE)样本特性获取更高质量/得率的纳米磁珠核酸提取方案,改进分子病理技术。方法 合成4大类15个小类的备选磁珠,以FFPE样本为中心,筛选高质量/得率磁珠。模拟常规组织、粗针穿刺(肝脏)、纤维支气管镜样本(肺),装管相同张数连片。采用筛选的最佳磁珠与市场出售的常见磁珠试剂提取核酸,横向对比纯化总量、片段大小等质量参数。应用PCR和Sanger验证核酸的下游应用。结果 以FFPE样本DNA为中心筛选自制纳米磁珠,获得最佳性能纳米磁珠总回收率为58.5%±1.58%,5种市售商品化磁珠和3种国产磁珠总回收率为18.68%~40.71%。相同组织量(连片)提取的DNA总量,在模拟常规组织、粗针穿刺和纤维支气管镜样本核酸得率比市售试剂盒提高39.49%~181.72%(P<0.05)。模拟纤维支气管镜样本1张(4μm)总量可达100 ng以上、5张总量可达400 ng以上。结论 以FFPE样本DNA为中心筛选的DNA纯化纳米磁珠,与商品化磁珠相比有较大提升,为临床分子病理检测的质量保证、自动化检测和项目拓展提供空间。 展开更多
关键词 石蜡包埋组织 Dna提取 纳米磁珠 PCR Sanger
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血浆差异表达miRNA预测脑膜瘤术后复发
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作者 王晓伟 高学军 +2 位作者 张波 郑安锡 罗霜 《中国临床神经外科杂志》 2024年第7期405-410,共6页
目的探讨血浆差异表达微小RNA(miRNA)在预测脑膜瘤术后复发中的作用。方法2017年5~9月前瞻性收集5例脑膜瘤和5例健康体检者的血浆样本,采用TaqMan低密度阵列(TLDA)分析鉴定差异表达的miRNA。2017年11月至2023年11月前瞻性收集脑膜瘤97例... 目的探讨血浆差异表达微小RNA(miRNA)在预测脑膜瘤术后复发中的作用。方法2017年5~9月前瞻性收集5例脑膜瘤和5例健康体检者的血浆样本,采用TaqMan低密度阵列(TLDA)分析鉴定差异表达的miRNA。2017年11月至2023年11月前瞻性收集脑膜瘤97例,术前PCR检测血浆差异表达miRNA,末次随访复查MRI判断肿瘤复发情况。结果TLDA分析共鉴定出9个差异表达miRNA(miR-21、miR-219-5p、miR-375、miR-190a、miR-451、miR-224、miR-107、miR-539、miR-197)。与未复发脑膜瘤病人比较,复发脑膜瘤病人血浆miR-21、miR-219-5p、miR-375、miR-190a表达量显著升高(P<0.05),血浆miR451、miR-224、miR-107、miR-539、miR-197表达量显著降低(P<0.05)。末次随访,15例(15.46%)出现复发。多因素Cox回归分析显示,血浆miR-21、miR-219-5p、miR-190a高表达以及血浆miR-107、miR-539、miR-224低表达均与脑膜瘤术后复发密切相关(P<0.05)。Kaplan-MeieR曲线分析显示,血浆miR-21≥2.64、miR-219-5p≥2.72、miR-190a≥1.82以及血浆miR-107≤3.78、miR-539≤4.69、miR-224≤4.59病人肿瘤无复发生存时间明显缩短(P<0.05)。结论脑膜瘤病人差异表达血浆miR-21、miR219-5p、miR-375、miR-190a、miR-451、miR-107、miR-539、miR-224、miR-197,监测这些miRNA可辅助预测脑膜瘤术后复发风险。 展开更多
关键词 脑膜瘤 术后复发 血浆 微小Rna
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制样方法对菊花花蕾激光显微切割样品RNA提取质量的影响
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作者 马月花 丁莲 +2 位作者 张雪 赵坤坤 陈素梅 《安徽农业科学》 CAS 2024年第18期1-5,9,共6页
[目的]研究不同固定剂及切片制样方式对菊花花蕾激光显微切割样品RNA提取质量的影响。[方法]以丙酮和乙醇冰醋酸2种试剂固定菊花花蕾,采用石蜡和冰冻切片2种方式制作样本,显微切割并收集最外两轮小花原基,提取RNA后比较提取质量。[结果... [目的]研究不同固定剂及切片制样方式对菊花花蕾激光显微切割样品RNA提取质量的影响。[方法]以丙酮和乙醇冰醋酸2种试剂固定菊花花蕾,采用石蜡和冰冻切片2种方式制作样本,显微切割并收集最外两轮小花原基,提取RNA后比较提取质量。[结果]石蜡和经梯度蔗糖保护的冰冻切片均能很好地保存花蕾组织形态,就石蜡切片而言,乙醇冰醋酸固定组织切割样品的RNA降解明显低于丙酮固定样品;而2种固定剂的冰冻切片切割样品RNA提取质量无明显差异。与石蜡切片相比,冰冻切片显微切割样品RNA质量更高。切割时收集管盖加入RNA提取缓冲液可明显缓解RNA降解。显微切割的不同品种菊花花原基与花发育有关的基因表达水平存在差异,表明切割获得的材料可用于下一步研究。[结论]植物组织经乙醇冰醋酸固定、梯度蔗糖保护后冰冻切片进行显微切割效果较佳,可富集特异组织或细胞并从中获得较高质量的RNA。 展开更多
关键词 固定剂 石蜡切片 冰冻切片 激光显微切割 Rna 提取质量
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Multifunctional anti-wax coatings for paraffin control in oil pipelines 被引量:6
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作者 Jie Bai Xu Jin Jun-Tao Wu 《Petroleum Science》 SCIE CAS CSCD 2019年第3期619-631,共13页
Paraffin deposition is a severe global problem during crude oil production and transportation.To inhibit the formation of paraffin deposits,the commonly used methods are mechanical cleaning,coating the pipe to provide... Paraffin deposition is a severe global problem during crude oil production and transportation.To inhibit the formation of paraffin deposits,the commonly used methods are mechanical cleaning,coating the pipe to provide a smooth surface and reduce paraffin adhesion,electric heating,ultrasonic and microbial treatments,the use of paraffin inhibitors,etc.Pipeline coatings not only have the advantages of simple preparation and broad applications,but also maintain a long-term efficient and stable effect.In recent years,important progress has been made in research on pipe coatings for mitigating and preventing paraffin deposition.Several novel superhydrophilic organogel coatings with low surface energy were successfully prepared by bionic design.This paper reviews different types of coatings for inhibiting wax deposition in the petroleum industry.The research prospects and directions of this rapidly developing field are also briefly discussed. 展开更多
关键词 paraffin control Coatings Surface energy BIONIC design WETTABILITY
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基于Na-BP-DME@C阳极的长寿命准固态钠-空气电池
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作者 赵振刚 牛文辉 +4 位作者 姚正银 侯敏杰 解志鹏 张达 梁风 《有色金属科学与工程》 CAS 北大核心 2024年第2期204-211,共8页
钠-空气电池因其能量密度高、成本低而成为金属-空气电池领域的研究热点。然而,以金属钠为阳极的钠-空气电池存在钠枝晶生长、金属钠界面稳定性差以及金属钠的反应活性高等问题,限制了钠-空气电池的快速发展。为解决上述问题,将联苯钠... 钠-空气电池因其能量密度高、成本低而成为金属-空气电池领域的研究热点。然而,以金属钠为阳极的钠-空气电池存在钠枝晶生长、金属钠界面稳定性差以及金属钠的反应活性高等问题,限制了钠-空气电池的快速发展。为解决上述问题,将联苯钠与导电炭黑复合材料Na-BP-DME@C作为阳极,单壁碳纳米角(SWCHNs)作为催化剂,构建准固态钠-空气电池。基于Na-BP-DME@C阳极的准固态钠-空气电池表现出优异的电化学性能,其电压差为1.5 V,功率密度为3.32 mW/cm^(2),在0.1 mA/cm^(2)电流密度下可稳定循环459 h(约459次)。 展开更多
关键词 准固态钠-空气电池 na-BP-DME@C阳极 长寿命
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基于NAS私有云的医院档案电子信息自动管理平台
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作者 孙琦 《办公自动化》 2024年第24期50-52,共3页
常规的医院档案电子信息自动管理平台主要使用HTMLPHP(Hyper Text Markup LanguageHypertext Preprocessor)超文本预处理语言生成多选项表单,易受服务器Post混乱作用的影响,导致综合运行性能低下,因此,提出一种基于NAS私有云的医院档案... 常规的医院档案电子信息自动管理平台主要使用HTMLPHP(Hyper Text Markup LanguageHypertext Preprocessor)超文本预处理语言生成多选项表单,易受服务器Post混乱作用的影响,导致综合运行性能低下,因此,提出一种基于NAS私有云的医院档案电子信息自动管理平台。硬件部分设计HGYUI4033处理芯片和KLOPA1存储器,软件部分利用NAS搭建档案电子信息管理私有云,生成档案电子信息自动管理架构,从而实现电子档案信息的自动管理。平台测试结果表明,文章设计的医院档案电子信息自动管理平台在不同状态下均能有序运行,综合性能良好,具有可靠性,有一定的应用价值,为提高档案综合管理效率、实现档案数字化管理升级作出一定的贡献。 展开更多
关键词 naS私有云 医院档案 电子信息 自动管理平台
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Hydrocarbon-Degrading Bacteria and Paraffin from Polluted Seashores 9 Years after the Nakhodka Oil Spill in the Sea of Japan 被引量:3
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作者 Kazue TAZAKI Hiroaki WATANABE +2 位作者 Siti Khodijah CHAERUN Koichi SHIRAKI Ryuji ASADA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第3期432-440,共9页
Pollution of petroleum hydrocarbons, in particular oil spills, has attracted much attention in the past and recent decades. Oil spills influence natural microbial community, and physical and chemical properties of the... Pollution of petroleum hydrocarbons, in particular oil spills, has attracted much attention in the past and recent decades. Oil spills influence natural microbial community, and physical and chemical properties of the affected sites. The biodegradation of hydrocarbons by microorganisms is one of the primary ways by which oil spill is eliminated from contaminated sites. One such spill was that of the Russian tanker the Nakhodka that spilled heavy oil into the Sea of Japan on January 2, 1997. The impact of the Nakhodka oil spill resulted in a viscous sticky fluid fouling the shores and affected natural ecosystems. This paper describes the weathering of hydrocarbon-degrading bacteria (genus Pseudomonas) and crystallized organic compounds from the Nakhodka oil spill-polluted seashores after nine years. The Nakhodka oil has hardened and formed crust of crystalline paraffin wax as shown by XRD analysis (0.422, 0.377, and 0.250 nm d-spacing) in association with graphite and calcite after 9 years of bioremediation. Anaerobic reverse side of the oil crust contained numerous coccus typed bacteria associated with halite. The finding of hydrocarbon-degrading bacteria and paraffin wax in the oil crust may have a significant effect on the weathering processes of the Nakhodka oil spill during the 9- year bioremediation. 展开更多
关键词 BIOREMEDIATION GRAPHITE HALITE heavy oil hydrocarbon-degrading bacteria paraffin wax Pseudomonas the nakhodka oil spill
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A Comparative Trial: The Safety and Clinical Efficacy of PEG 3350 and Liquid Paraffin in Management of Chronic Functional Constipation in Children 被引量:4
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作者 Abbaslou Parvin Abbaslou Farzaneh Hosseini Nasab Ali 《International Journal of Clinical Medicine》 2012年第5期383-386,共4页
Background: Constipation is one of the most common problems in the pediatric age group. In the vast majority, chronic constipation is idiopathic or functional. In addition to education and behavioral changes, disimpac... Background: Constipation is one of the most common problems in the pediatric age group. In the vast majority, chronic constipation is idiopathic or functional. In addition to education and behavioral changes, disimpaction and maintenance treatment with medications are the main pillars of successful outcome. The medications are variably effective and have potential side effects. Objectives: The current clinical trial was designed to evaluate clinical efficacy of polyethylene glycol (PEG) 3350 and liquid paraffin in chronic functional constipation. Besides, subjects were followed carefully for the side effects. Material and Methods: This study was involved 110 children suffering from chronic functional constipation. They were placed into two different groups, randomly. Each group was treated with PEG 3350 or liquid paraffin. The clinical efficacy and side effects were monitored. Results: After disimpaction with bisacodyl suppositories or combined with Mineral oil enemas in hard fecal impaction, maintenance therapy with PEG 3350 or liquid paraffin was started. The treatment duration and efficacies were not different between the two groups. Furthermore, serious adverse drug reaction was not observed. The family history of constipation and presence of incontinence were two worse prognostic factors. Conclusion: No difference was observed between PEG 3350 and liquid paraffin in chronic functional constipation in children in terms of their efficacies. They are safe and effective medications in this age group. 展开更多
关键词 Children CONSTIPATION Liquid paraffin POLYETHYLENE GLYCOL
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基于NAS和教学诊改的多模态教学大数据存储访问优化研究
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作者 王雅婷 孙宗凌 《电脑知识与技术》 2024年第24期81-84,共4页
本文提出一种基于网络附加存储(NAS)和教学诊断与改进(诊改)的多模态教学大数据存储与访问优化方案。该方案通过NAS实现多模态教学资源的集中存储、高效管理和安全共享,利用这些多模态教学数据实现教学活动的持续诊断改进和教育质量的... 本文提出一种基于网络附加存储(NAS)和教学诊断与改进(诊改)的多模态教学大数据存储与访问优化方案。该方案通过NAS实现多模态教学资源的集中存储、高效管理和安全共享,利用这些多模态教学数据实现教学活动的持续诊断改进和教育质量的提升。本文分析了NAS和多模态教学数据的特点、存储要求以及NAS在其中的应用。在此基础上,本文结合教学诊改流程,设计了基于NAS的多模态教学大数据存储优化方案。 展开更多
关键词 网络附加存储(naS) 教学诊改 多模态教学 大数据 存储优化
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Paraffin section observation of flower bud differentiation of Chimonanthus praecox in Kunming and comparison of the differentiation processes in different regions,China 被引量:5
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作者 Sijin Li Nan Yang Longqing Chen 《Horticultural Plant Journal》 SCIE CSCD 2022年第2期221-229,共9页
Chimonanthus praecox is an important ornamental plant and cut flower material in China.It blooms in the freezing winter and its flower emits charming fragrance.However,in different region the flowering time is variabl... Chimonanthus praecox is an important ornamental plant and cut flower material in China.It blooms in the freezing winter and its flower emits charming fragrance.However,in different region the flowering time is variable.In order to understand the flowering mechanism of Ch.praecox in the winter,we studied the flower bud differentiation in Spring City-Kunming using paraffin sectioning method in the present study.Meanwhile we compared the differentiation process difference from different regions.It was found that the temperature is the key factor for its flower bud differentiation and blossom of Ch.praecox.In the process of bud differentiation,the temperature 20℃was the optimum for inducing changes from vegetative axillary buds to reproductive buds and subsequent morphological differentiation in Ch.praecox.Furthermore in the first three differentiation periods—tepal primordial stage,staminal primordial stage and pistil primordial stage,Kunming took the shortest time to finish the process due to very rapid temperature rise to 20℃,whereas,in Zhengzhou the time for these differentiations was the longest,which may be caused by the slow temperature rise.After May,the high temperature stress forced the flower buds into the first long dormant period in all regions except Kunming.In Kunming,the average temperature was only 20–25℃,so the flower bud continued to differentiate.In all regions,Kunming is the first to complete whole flower bud differentiation even on the early August,and started the second dormancy very early but very long.In the other regions,the plants went through a shorter dormancy and the low temperature broke the dormancy rapidly.Contrarily the plants of Kunming spent a longer period for the low temperature.Thus,the low temperature less than 10℃is a key factor to breaking the second dormancy.Surely the regular effects of temperature on flower bud differentiation and blossom is very helpful for florescence regulation of Ch.praecox. 展开更多
关键词 Chimonanthus praecox Flower bud differentiation paraffin section TEMPERATURE
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Paraffin/SiC as a Novel Composite Phase-Change Material for a Lithium-Ion Battery Thermal Management System 被引量:2
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作者 Wei Kang Yiqiang Zhao +3 位作者 Xueheng Jia Lin Hao Leping Dang Hongyuan Wei 《Transactions of Tianjin University》 EI CAS 2021年第1期55-63,共9页
A lithium-ion battery thermal management system has always been a hot spot in the battery industry. In this study, a novel high-thermal-conductivity composite phase-change material(CPCM) made by paraffin wax and silic... A lithium-ion battery thermal management system has always been a hot spot in the battery industry. In this study, a novel high-thermal-conductivity composite phase-change material(CPCM) made by paraffin wax and silicon was adopted to facilitate heat transfer. Moreover, high resistance or even insulation of CPCM is capable of preventing short circuits between the cells. The heat transfer mechanism of CPCMs was determined under a scanning electron microscope. A thermogravimetric analyzer was employed to determine the thermal stability. A diff erential scanning calorimeter was used to explore the thermophysical properties of the composite samples. By comparing the results of the experiment, it was reported that under the silicon carbide content of 5%, the parameters were better than others. The phase-change enthalpy of CPCM was 199.4 J/g, the leakage rate of liquid was 4.6%, and the melting point was 53.6℃. To verify the practicality of CPCM, a three-dimensional layered battery pack model was built in the COMSOL Multiphysics software. By simulating the thermal runaway inside the battery packs of various materials, it was reported that the addition of CPCM significantly narrowed the temperature range of the battery pack from 300–370 to 303–304 K. Therefore, CPCM can eff ectively increase the rate of heat transfer to prevent the chain of thermal runaway reactions. It also enables the battery pack to run at a stable temperature. 展开更多
关键词 Lithium-ion battery Phase-change material paraffin Silicon carbide Thermal runaway
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Retrospective Analysis of Diagnosis by Intraoperative Frozen Section and Routine Paraffin Embedded Tissue in 638 Thyroid Disease Patients 被引量:3
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作者 Chunyan Xing Liwu Dong +1 位作者 Xiaohong Wang Wei Li 《Clinical oncology and cancer researeh》 CAS CSCD 2009年第5期359-361,共3页
OBJECTIVE To summarize a common pathogenefic condition, the pathologic characteristics shown in frozen section and our experience utilizing 2 different common thyroid diseases (TD). diagnostic methods in cases of ME... OBJECTIVE To summarize a common pathogenefic condition, the pathologic characteristics shown in frozen section and our experience utilizing 2 different common thyroid diseases (TD). diagnostic methods in cases of METHODS Data from 638 cases with frozen sections from thyroid tissue were retrospectively analyzed. The intraoperative frozen sections of the patients and postoperative diagnostic results of routine paraffin sections were compared. RESULTS In the 683 patients, the gender ratio of females to males was 2.64 : 1, and the ratio between the patients with nodular goiter (NG) and the patients with thyroid adenoma was 1.5 : 1. The oldest age group of patients with thyroid cancer (TC) ranged from 40 to 49 years. Frozen section pathologic examination has been employed more and more in the diagnosis of thyroid diseases, and the detection rate of TC has increased year by year, i.e., the rate increased to 6.45%, 7.58%, 14.55% and 16.57%, respectively, in 2005, 2006, 2007 and 2008. Thyroid papillary carcinoma (TPC) was the most commonly seen malignant tumor of the thyroid (MTT), which accounted for approximately 94.8% of MTTs and 11.44% of the total TDs. Micropapillary carcinoma accounted for 27.4% of TPC, and multifocal carcinomas accounted for 15.58% of TCs. Many of the TCs (19.48%) were complicated by benign diseases such as adenoma, NG and thyroiditis. The coincidence rate of diagnoses made by frozen section and paraffin embedding for thyroid disease was 98.59%. Calcification was rather common in NG and TPC, and there were significant differences in psammoma bodies (PMB) between the calcifications of TPC and NG (P 〈 0.01). CONCLUSION TPC ranks first in the incidence of MTTs and accounts for 94.8% of all MTTs. About 1/4 of TPCs are micropapillary carcinoma, while 1/5 are accompanied by benign disease, such as adenorna, NG and thyroiditis. PMB are of importance and of significance in the diagnosis of TPC. 展开更多
关键词 thyroid disease intra-operative frozen section paraffin imbedding pathologic analysis.
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低盐水体Na^(+)/K^(+)对凡纳滨对虾生长、体成分与肝胰腺、鳃组织结构的影响 被引量:2
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作者 祝华萍 苏家齐 +4 位作者 张子军 朱长波 张博 李婷 陈素文 《水产学报》 CAS CSCD 北大核心 2024年第3期87-95,共9页
缺钾在内陆低盐度盐碱水中经常发生,为探究低盐水体中不同钾缺乏程度对凡纳滨对虾生长、存活、体成分以及鳃和肝胰腺组织结构的影响,实验参照海水离子组成配置盐度为2的低盐度水体,在Na^(+)/K^(+)(mg/mg)比值为27、47、67、87、107 (分... 缺钾在内陆低盐度盐碱水中经常发生,为探究低盐水体中不同钾缺乏程度对凡纳滨对虾生长、存活、体成分以及鳃和肝胰腺组织结构的影响,实验参照海水离子组成配置盐度为2的低盐度水体,在Na^(+)/K^(+)(mg/mg)比值为27、47、67、87、107 (分别记为A、B、C、D、E组)的条件下,对体重为(1.04±0.23) g的凡纳滨对虾幼虾开展了为期60 d的养殖实验。结果显示,E组对虾的存活率为44.64%±20.95%,显著低于A、B、D三组;E组体重为(4.86±0.66) g,显著低于其他4组;A~D组之间的湿重、增重率、特定生长率差异不显著,但均大于E组且差异显著;在饲料系数上,E组最高并与A、D组差异显著。在体成分上,各组全虾钾含量、灰分含量差异不显著,E组的水分含量高于其他组,并与A、B组差异显著;E组粗蛋白含量最低,且与B组差异显著。E组对虾鳃组织角质层明显受损,红细胞数量减少,空泡增多,肝胰腺B细胞及其内部转运泡体积增大,肝小管结构受损。研究表明,低盐条件下严重缺钾引起了对虾鳃和肝胰腺损伤,降低了对虾的存活率和生长率;水体缺钾在前期即可对对虾的生长产生明显影响,而对存活的影响随养殖时间的增加而增大。实验结果有助于为内陆低盐度盐碱水养殖凡纳滨对虾提供理论依据。 展开更多
关键词 凡纳滨对虾 na^(+)/K^(+) 生长 体成分 组织结构
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