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1.
高山仰止,景行行止;先生百年,谨赋为纪。 锦绣吴中,先生故里;其父以仁,一代名医。爱之如珠,教之以礼;孔孟儒学,从小沐浴。三十年代,血雨腥风;沪上游行,租界被拘。先生愤慨,目光如炬:“斯是吾国,关尔何事!”言语铿锵,巡捕无语。经此一事,明白一理:落后挨打,国弱被欺。立志救国,发奋学习。遂考清华,选修物理。为求深造,留学德域;师从迈特,才攀居里;名师相教,如虎添翼。漫步科学,畅游物理;先生勤勉,硕果丰裕。  相似文献   

2.
本文介绍了利用火焰原子吸收分光光度法对宁夏野生白刺果汁上浮物中的铜,锌,铁,锰,钾,钠,钙和镁含量进行的研究工作。白刺果汁上浮物经湿消解法处理后,用原子吸收法测定。方法简单,快速,具有灵敏度和精密度高,选择性好,试剂消耗量小等优点。本法测定铜,锌,铁,锰,钾,钠,钙和镁的回收率均在91.1-107.2%之间,变异系数均不超过5.3%。结果满意。  相似文献   

3.
非晶金刚石膜的性能及其应用   总被引:1,自引:0,他引:1  
非品金刚石薄膜具有超高硬度等一系列优异的特殊性能,为工程界孜孜追求的材料表面镀膜。用百纳科技公司研发制造的过滤阴极真空电弧离子镀膜机镀制的非晶金刚石薄膜,SP^3金刚石结构量≥80%,硬度高,膜/基结合力高,摩擦系数小,耐磨损,耐腐蚀,透光率高,在电子,机械,光学,生物医学上有广泛应用前景。我们已在视窗玻璃,丝锥,模具,硬质合金刀头等产品上成功应用。  相似文献   

4.
1.来稿要求科学性准确,逻辑性强,文字简练,数据可靠,图表清晰,具有创新性或一定新意。每篇文章字数(包括图、表)以不超过6000字为宜。来稿(按顺序)必须包括:题目,作者姓名,作者单位(包括所在地和邮政编码),中文摘要(不超过300字),关键词(3-8个),中图分类号,正文,参考文献。2.投稿时要求有文字稿和电子稿。文字稿须打印在A4纸上,留足行距,单面打印,标点符号正确,量和单位的符号符合国家标准。文中的外文字母分清大、小写,正、斜体;上、下角标的字母数码及符号的位置要准确。文中图表要精选。图画面要清晰,照片黑白清…  相似文献   

5.
《光谱实验室》2007,24(1):87
孔子,名丘,字仲尼,今山东省曲阜市人。先世是贵族。幼年贫贱,学无常师,做过小吏。年50任鲁司寇,摄行相事。后与门人周游卫、陈、蔡等国,终不见用。晚年致力于教育事业,整理《诗》、《书》等典籍,删定《春秋》。传弟子3000人,著名者72人。政治上主张“正名”,认为“君君、臣臣、父父、子子”,都应名实相副。反对苛政,提出“不患寡而忠不均,不患贫而患不安”。伦理思想上宣传“仁”。  相似文献   

6.
用消去法推求原子谱项   总被引:5,自引:1,他引:4  
提出了确定复杂组态的Slater函数和原子谱项的程序化方法。运用Pascal语言编制了计算程序,利用本程序可准确地导出等效组态s^N,p^N,d^N,f^N,g^N,h^N,i^N,k^N,l^N,m^N,n^N,o^N,q^N,r^N,t^N,u^N,v^N,w^N,x^N,y^N,z^N的L-S耦合谱项和Slater函数。迄今为止,还未见国内外文献报道过。  相似文献   

7.
虚火花电子束源研制成功   总被引:6,自引:4,他引:2  
王明常  朱俊彪 《光学学报》1995,15(2):55-255
虚火花电子束源研制成功王明常,朱俊彪,王之江,张立芬,陆载通,陆宾,冯诚士,黄羽.周慧芬(中国科学院上海光学精密机械研究所,上海201800)高功率,强流密度,高亮度虚火花电子柬源运转成功。近日出束,取得重大进展。座火花放电是在一种特殊结构称为虚火花...  相似文献   

8.
霜形成对翅片管式蒸发器性能影响的研究   总被引:7,自引:0,他引:7  
符号表A面积,mZ7汽化游热、kJ/kgi冰a热扩散半,m‘/s。运动粘度,m勺sdn进口C质量百分数6厚度,mfat潜热D质扩散}.4{,ma/sP密度,ng/m‘e出口7烩,*U一,时间,S,管排m质量,kgA导热系数,W/inKs饱和状态M质流量,ug/s。含湿量,ng水儿g空气sen显热Q制冷量,W下角T总的R气体常数a空气I管S间距,mb翅片间的中心位置。蒸气T温度,KF霜w壁面。;。;w,x,y,z向速度,m/s/翅片x和距离有关的局部分量1目u竟亏目前,热泵的应用越来越广泛,所遇到的最大问题就是蒸发器的结霜问题。结霜使蒸发器的传热情况恶化,同时使…  相似文献   

9.
本文广泛地收集了有关内耗,力学谱,超声衰减方面的专著及会议文集。反映了20世纪在此领域的英文,俄文出版的书籍。也列出了历次国际会议及前苏联,乌克兰,中国的国内会议。文中包括了点缺陷,电,声子,位错,晶界,电畴等诸方面在内的内耗与力学谱工作。  相似文献   

10.
人物介绍     
《技术物理教学》2006,14(4):F0004-F0004
何新凤,女,瑶族,45岁,学士,教授,工程师,广西生态工程职业技术学院学术带头人,双师素质教师。主要研究方向:教学评价和教育信息化。中国物理学会教学委员会职教分委会和中国教育学会物理教学专业委员会职教工委会委员,  相似文献   

11.
研究了用碳粉、碳酸钙、氧化铜和氧化铍作缓冲剂同时测定钛基复合材料中的镍、铁、钼、锰和硼的发射光谱法,选择铍作内标线,不需分离、不需化学处理,直接压样于杯形的石墨电极中,具有简便、快速、准确。对测定条件、干扰因素进行了研究,从而建立测定镍、铁、钼、锰和硼的新方法。镍、铁、钼、锰和硼的分析线分别为300.36,248.33,315.82,260.57和249.68 nm,内标线选择为铍的298.61 nm,镍、铁、钼、锰和硼的线性范围分别为0.003%~0.30%;0.001%~0.20%;0.003%~0.30%;0.001%~0.20%;0.001%~0.20%。镍、铁、钼、锰和硼的检测限分别0.003%,0.001%,0.003%,0.001%,0.001%,其回收率在95.80%~104.8%范围内,当n=9时,相对标准偏差RSD均小于5%。用于样品的测定取得了满意的结果。  相似文献   

12.
To prevent the natural processes of decay and to develop and improve the treatments of conservation and restoration of artistic bronzes meaning statues and sculptures, it is important understanding the patination processes and the knowledge of artificially corroded surfaces. Chemical and physical characterization of artificial patinas obtained on artistic bronzes and coppers by using the 19th century Western traditional patination techniques and recipes by means of SEM-EDS, light microscopy and ATR/FT-IR has been done in previous studies [I.Z. Balta, L. Robbiola, Characterization of artificial black patinas on artistic cast bronze and pure copper by using SEM-EDS and light microscopy, in: Proceedings of the 13th European Microscopy Congress, 22-27 August 2004, Antwerp, Belgium, EMC 2004 CD-Rom Conference Preprints; I.Z. Balta, L. Robbiola, Traditional artificial artistic bronze and copper patinas—an investigation by SEM-EDS and ATR/FT-IR, in: Proceedings of the 8th International Conference on Non Destructive Investigations and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage, 15-19 May 2005, Lecce, Italy, ART’05 CD-Rom Conference Preprints]. Differences in morphology (structure, thickness, porosity, adherence, compactity, uniformity, homogeneity) and also in composition, on both artistic cast bronze and pure copper patinas, were clearly evidenced. Further in-depth investigation is required to be carried out in order to better understand the patinas mechanisms of formation and the layers kinetics of growth. The elemental and chemical analysis, either on a surface monolayer or in a depth profile, by using the Secondary Ion Mass Spectrometry (SIMS) and X-ray Photoelectron Spectroscopy (XPS) techniques, can provide this kind of information, unique at trace-level sensitivity. SIMS has proved to be a suitable analytical technique for analyzing small amounts of material with high atomic sensitivity (ppm or even ppb) and high depth/lateral resolution in the micron and sub-micron range [R.G. Wilson, F.A. Stevie, C.W. Magee, Secondary Ion Mass Spectrometry: A Practical Handbook for Depth Profiling and Bulk Impurity Analysis, Wiley & Sons, New York, 1989; M. Dowsett, A. Adriaens, The role of SIMS in cultural heritage studies, Nucl. Instr. Meth. Phys. Res. B 226 (2004) 38-52]. XPS has the ability to provide detailed chemical information on virtually each kind of solid sample, and elemental identification is therefore possible due to the core level photoemission. The most important advantage is the high surface sensitivity of the chemical information (a few monolayers) [E. Ciliberto, G. Spoto, Modern Analytical Methods in Art and Archaeology, John Wiley & Sons, Inc., New York, 2000]. In addition elements’ relative abundance can be made semi-quantitative or quantitative and information on chemical bonds can be derived.The aim of the present work is to highlight the advantages and the limits of XPS and Dynamic SIMS surface analytical techniques for the characterization of artistic bronze and copper artificial patinas. The results obtained on the analyzed samples allowed the distribution of the main elements in the corrosion patinas layers and the contribution of each elements present in bronze matrix to the color of the resulting patinas to be precisely revealed. This information could be used for comparative studies between artificial and natural patinas, and also for provenience and authentication studies for artistic and archaeological bronzes.  相似文献   

13.
朱小梅 《光谱实验室》2011,28(5):2558-2561
用ICP-AES测定陕西汉中市中药姜黄中的2种常量营养性元素(钙、镁)和5种微量元素(铜、铬、铁、锌、锰)含量.钙6010.5μg·g-1、镁6250.1μg · g-1、铜18.8μg·g-1、铬4.2μg·g-1、铁331.8μg·g-1、锌208.6μg·g-1、锰477.4μg·g-1,加标回收率均在96.4%...  相似文献   

14.
火焰原子吸收光谱法测定磁化杯中铅、镉和铁   总被引:1,自引:0,他引:1  
本文研究了火焰原子吸收光谱法测定磁化杯陶瓷内胆中Ph、Cd和Fe含量的方法。样品经粉碎,用硝酸-高氯酸混合液进行消解后测定。本法灵敏度高,干扰少,简单,快速,具有良好的精密度和准确度,其相对标准偏差分别为Pb3.99%,Cd10.7%,Fe0.9%。回收率Pb100.61%,Cd101.18%,Fe102.4%。  相似文献   

15.
Energy, exergy, and exergoeconomic evaluations of various geothermal configurations are reported. The main operational and economic parameters of the cycles are evaluated and compared. Multi-objective optimization of the cycles is conducted using the artificial bee colony algorithm. A sensitivity assessment is carried out on the effect of production well temperature variation on system performance from energy and economic perspectives. The results show that the flash-binary cycle has the highest thermal and exergy efficiencies, at 15.6% and 64.3%, respectively. The highest generated power cost and pay-back period are attributable to the simple organic Rankine cycle (ORC). Raising the well-temperature can increase the exergy destruction rate in all configurations. However, the electricity cost and pay-back period decrease. Based on the results, in all cases, the exergoenvironmental impact improvement factor decreases, and the temperature rises. The exergy destruction ratio and efficiency of all components for each configuration are calculated and compared. It is found that, at the optimum state, the exergy efficiencies of the simple organic Rankine cycle, single flash, double flash, and flash-binary cycles respectively are 14.7%, 14.4%, 12.6%, and 14.1% higher than their relevant base cases, while the pay-back periods are 10.6%, 1.5% 1.4%, and 0.6% lower than the base cases.  相似文献   

16.
Recent interest in biomass-based fuel blendstocks and chemical compounds has stimulated research efforts on conversion and upgrading pathways, which are considered as critical commercialization drivers. Existing pre-/post-conversion pathways are energy intense (e.g., pyrolysis and hydrogenation) and economically unsustainable, thus, more efficient process solutions can result in supporting the renewable fuels and green chemicals industry. This study proposes a process, including biomass conversion and bio-oil upgrading, using mixed fast and slow pyrolysis conversion pathway, as well as sono-catalytic transfer hydrogenation (SCTH) treatment process. The proposed SCTH treatment employs ammonium formate as a hydrogen transfer additive and palladium supported on carbon as the catalyst. Utilizing SCTH, bio-oil molecular bonds were broken and restructured via the phenomena of cavitation, rarefaction, and hydrogenation, with the resulting product composition, investigated using ultimate analysis and spectroscopy. Additionally, an in-line characterization approach is proposed, using near-infrared spectroscopy, calibrated by multivariate analysis and modeling. The results indicate the potentiality of ultrasonic cavitation, catalytic transfer hydrogenation, and SCTH for incorporating hydrogen into the organic phase of bio-oil. It is concluded that the integration of pyrolysis with SCTH can improve bio-oil for enabling the production of fuel blendstocks and chemical compounds from lignocellulosic biomass.  相似文献   

17.
对于常规储层,核磁共振是一项十分有效的解释-评价技术,它既能评价岩石物性与孔隙结构,又能评价孔隙流体分布与饱和度,且具有快速、无损、经济等特点;而对于页岩储层,其核磁共振受纳米级孔隙、复杂矿物成分、特殊孔隙结构、较高有机质含量、超低渗透性及内部梯度和受限扩散等因素的影响,面临探测分辨率低、解释模型不适用等瓶颈.为了发挥该项技术在页岩油气勘探开发中的作用,将国内外的页岩油气层核磁共振分析、评价技术与相关的页岩油气层实验室微观分析成果相结合,进行了系统梳理,从探测分辨率的提高、孔隙结构与岩石物性评价模型的建立、孔隙流体分布与识别模型的建立等方面进行了综述,提出需加强纳米孔的核磁共振弛豫机理和提高 D-T2二维谱分辨率两个基础研究,在此基础上,进一步完善岩石物理及孔隙流体两个评价模型.
  相似文献   

18.
Versatile manipulation of lanthanide photoluminescence not only enables a more thorough understanding of the luminescent mechanism, but also promotes their widespread applications including advanced display and security, bioimaging and biotherapy, and sensors. The traditional chemical methods, engineering of composition, concentration, size, morphology, and surface defects, can easily tune the excitation, energy transfer and emission processes and have been frequently used. Despite the powerful ability to control luminescence intensity and selectivity, these chemical approaches suffer from cumbersome synthesis processes and are usually time consuming and irreversible. Recently, there have been numerous examples of physical approaches realizing in situ, real time, and reversible luminescence manipulation for certain materials under a given excitation. Herein, the existing physical strategies comprising temperature, magnetic field, electric field, and mechanical stress are summarized. For each approach, the action mechanism, material design, applications, as well as current challenges are discussed, and possible development directions and broadening of the potential application areas are considered.  相似文献   

19.
There are three main astrophysical combustion systems: the evolution of stars, formation of interstellar dust and particulates, and the transition to hadrons in the early universe. These are described in terms of general combustion concepts, such as ignition, laminar and turbulent flames, detonations, multiphase flows, and particle and soot formation. Viewed in this way, the universe and many of its most important astronomical components are combustion systems, and we should use these as naturally occurring laboratories for exploring new and familiar combustion regimes. A more detailed discussion focuses on one type of combustion system, the ignition and development of turbulent flames in Type Ia supernovae, and the importance of the transition to a detonation.  相似文献   

20.
采集了石河子城区32个站点的道路尘土样本,测定了样品中10种非常规监测微量元素(B,Be,Bi,Co,Ga,Li,Sb,Sn,Tl,V)的含量。并采用地积累指数法、元素相关性分析和主成分分析法对尘土中的微量元素污染程度和来源进行了分析。结果表明:道路尘土中微量B,Be,Bi,Co,Ga,Li,Sb,Sn,Tl和V的平均含量分别为41.11,1.68,0.52,13.58,36.26,24.91,3.37,3.64,0.42,72.66 mg·kg-1。其中,Co,Li和Tl的平均含量均低于新疆土壤元素背景值,B,Be和V的平均含量和新疆土壤元素背景值相似,Bi,Ga,Sb和Sn的平均含量高于新疆和世界土壤元素背景值。地积累指数计算结果表明:B,Be,Co,Ga,Li,Tl和V污染级数为0,说明无污染,而Sb,Bi和Sn污染较为严重(污染等级分别为2,1,1)。元素相关性分析和主成分分析多元统计方法计算结果表明,Bi,Co,Sb和Tl主要是人为来源,B,Be,Li和V主要是自然来源,而Ga和Sn可能受自然因素和人为因素的共同影响。  相似文献   

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