Microstructure Evolution of Ni-based Single Crystal Superalloy During Heat-treating

利用螺旋选晶法制备了镍基单晶合金,研究了热处理过程中合金的组织演变。结果表明:合金的铸态组织由枝晶组成,W偏析于枝晶干,Ti、Cr、Mo和Ta偏析于枝晶间,固溶处理可以消除铸态组织中的枝晶,减小成分偏析,固溶温度越高,粗大的γ’和γ/γ’共晶溶解的越完全。时效处理过程中,大尺寸的γ’发生粗化,小尺寸的γ’逐渐消失,时效温度越高,γ’粗化得越严重。热处理促进合金元素在γ和γ’中的均匀分布,减小了合金的错配度

基于约束的神经机器翻译

神经机器翻译是近几年出现并快速发展的一种深度学习驱动的新型机器翻译模式,目前已成为机器翻译学术和工业界广为接受的主流技术.本文总结了我们在神经机器翻译方面的工作,特别是在各种信息和知识约束条件下提出的一系列神经机器翻译模型和方法,具体包括隐变量约束的变分神经机器翻译模型、单词与短语级统计机器翻译译文推荐与约束模型、源端句法结构约束模型.除此之外,本文也对神经机器翻译未来发展进行了初步思考和展望.国家自然科学基金优秀青年基金(批准号:61622209)资助项

Types of participatory research based on locus of decision making

文章以环太湖53条出入湖河流为研究对象,测定2009年12月至2010年3月间（枯水季节）溶解态重金属含量,结果表明Mn、Ni、Cu、Zn、Cr、As等六种重金属溶解态浓度含量均较低,且未超标。将53条河流出入湖区域分为无锡常州区、宜兴区、湖州区、苏州区四个区域,无锡常州区除Cd外,其它重金属含量最高;Cd在宜兴区含量最高,湖州区含量次之,且超标现象严重;苏州区河流由于大部分时间出湖,故各重金属含量最低,水质最好

Design and measurements of the high gradient accelerating structures

The purpose of this thesis was to study on design and measurements of the high gradient accelerating structures. After introducing the main parameters to characterize Linacs we explained the application of the periodic accelerating structure. Then we studied TW accelerating structure operating at K-band frequency in order to linearize longitudinal space phase to increase beam brightness in the framework of the Compact Light XLS project in order to produce hard x-ray. We estimated group velocity as a function of frequency both analytically and numerically. Analytical results have a good agreement with the numerical results. The main parameters such as shunt impedance, quality factor (Geometric factor) and R/Q independently from the operating frequency for the TM010, TM110 and TM011 for a single cylindrical “pill-box” have been determined analytically as they provide accurate model for the accelerating structures. In order to characterize a normal conducting high accelerating structure with maximum gradients operating at X-band with extremely low probability of RF breakdown, an electroformed SW structures has been fabricated and characterized by SLAC and INFN with collaboration of other institute around the world at 11.424 GHz, coated with Au-Ni. We designed a gold plate RF high gradient structure operating at the X- band coated with Au-Ni. Bench measurements have been performed in the Department of SBAI of the University of Rome “La Sapienza”. The Slater method for the SW cavity has been employed in order to quantify the electric field inside the structure. Comparing the results with the results exposed from HFSS we report the features that have been quantified, showing good agreement. We continued working on the perturbation effect due to the aperture coupled between a waveguide and a cavity but for our application in SW multi-cell high gradient accelerating structure we studied on theoretical approach for reflection coefficient calculation in a SW cavity coupled to a waveguide. One method was based on circuit theory in which we found the overall Q of a resonant circuit for a cavity coupled to an external waveguide containing the RF generator. Q calculation led to the determining of the shunt impedance and consequently the reflection coefficient calculation. Comparison of the results shows a good agreement with the numerical results carried out by using the numerical code, HFSS. Another method of reflection coefficient calculation has been accomplished. We applied the modified Bethe’s theory presented by Collin and developed by De santis, Mostacci and L.Palumbo for TM01 mode cavities coupled by a small hole with a thickness size comparable to the wavelength. The amplitudes of forward and backward waves due to polarizabilites have been determined and we found equations for reflection and transmission coefficients. We demonstrated that our equation for reflection coefficient calculation is an analogous of the reflection coefficient obtained by Collin for TE10 using the circuit theory

1,4-丁炔二醇温和条件下PdNi基加氢催化剂的研究

鉴于丁炔二醇加氢制丁二醇的生产工艺一般涉及高压/高温,以α-Al2O3或碳纳米管（CNTs）为载体,研发了近室温近常压下1,4-丁炔二醇的Pd（Ni）基催化剂的加氢性能及其结构特征。结果发现,双金属PdNi基催化剂可以实现丁炔二醇的完全转化。对于产物丁二醇的选择性,还原法制备的PdNi/CNTs仅达60.6%,而浸渍法制备PdNi/α-Al2O3和PdNi/CNTs则可达89.1%和98.9%。X射线衍射（XRD）、氢气程序升温还原（H2-TPR）及透射电镜（TEM）等表征结果表明,具有合适相互作用、合金形式（部分）以及高度分散的Pd-Ni物种对丁炔二醇加氢具有重要作用,有利于反应中间产物丁烯二醇进一步加氢至丁二醇。而CNTs具有较优的储氢能力,以CNTs为载体有利于提高PdNi基催化剂表面的氢浓度,进而促进丁烯二醇加氢。中央高校基本科研业务费专项(20720170029

一种联合检测乙型肝炎病毒前S1抗原与核心抗原方法的建立及其与病毒核酸检测结果的一致性

本研究以与血清中HBV DNA含量高度相关的两种HBV抗原(前S1抗原与核心抗原)为靶标,建立了联合检测这两种HBV核酸相关抗原(NRAg)的双抗体夹心法ELISA试剂。对系列稀释血清的检测表明,该试剂的平均分析灵敏度为103.2基因组拷贝/mL(95%可信限102.2-4.2基因组拷贝/mL),显著高于前S1抗原或核心抗原的单独检测。对994份HBsAg阴性血清的检测结果表明NRAg ELISA的特异性为99.7%(95%可信限:99.1%~99.9%)。对271份临床慢性肝炎血清进行检测,结果NRAg ELISA与HBV DNA结果的总符合率达96.3%(95%可信限:93.3%~98.2%),NRAg ELISA的读值/临界值比(S/CO)与HBV基因组拷贝数呈正相关。利用NRAg试剂,发现了1例HBsAg"a"抗原表位突变的变异株。这些结果显示HBV NRAg ELISA与HBV DNA具有高度相关性,并能够检测出HBsAg抗原变异株,有望成为HBsAg变异株筛选的有力工具,并为广大基层医疗单位提供一种便捷的替代HBV DNA定性检测的手段

Study on HPLC Fingerprint of Chinese Marine Medicine Dried Scallop

目的建立海洋中药干贝高效液相色谱(HPlC)指纹图谱分析方法 ,为其质量控制和药材鉴别提供依据。方法采用反相AllTIMA-C18柱,水(A)和乙腈(b)为流动相,梯度洗脱,流速为0.8Ml/MIn,检测波长210nM,柱温20℃,进样体积30μl;采用高效液相色谱二极管阵列检测器-质谱联用技术(HPlC-dAd-MS)对其特征峰进行快速分析;采用相似度计算软件用于10批干贝药材的相似度评价。结果初步建立了干贝药材的HPlC指纹图谱,10批干贝药材指纹图谱有9个共有峰,相似度均在0.85以上;HPlC-dAd-MS分析获得的4个特征峰的紫外光谱和质谱信息,可用于干贝药材指纹图谱特征峰以及共有峰的准确确定。结论该方法准确、简单、稳定性好,为干贝药材的真伪鉴别及质量控制提供了科学依据。Objective To establish a chromatographic fingerprint of Dried Scallop,a kind of Chinese marine medicine,by high performance liquid chromatography (HPLC),and apply for quality assessment and control of medicine materials of Dried Scallop.Methods Separation was performed on an Alltima-C18 (250 mm × 4.6 mm,5μm),with mobile phase consisting of water (A) and acetonitrile (B) with gradient elution at the flow rate of 0.8 ml/min.The UV detection wavelength was 210 nm,column temperature was 20℃.Characteristic peaks of the fingerprint could be rapidly analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS),and the software of similarity analysis was used to calculate the similarity of all the Dried Scallop samples.Results All samples tested contained the same nine peaks,and the similarities of 10 batches of Dried Scallop were more than 0.85.MS and UV spectra of the 4 characteristic peaks obtained using HPLC-MS could be used to accurately confirm the characteristic and common peaks in fingerprint of Dried Scallop.Conclusion This method is simple,accurate and stable,and can provide scientific reference for the identification and quality control of Dried Scallop.国家自然科学基金(No.20602009;20905017);海洋公益性行业科研专项(No.200705011;200805039

Concentration and distribution of polycyclic aromatic hydrocarbons in surface sediments collected in the Southern Yellow Sea

采用气相色谱与质谱联用(gC/MS)技术,在一个航次内对南黄海表层沉积物中16种优先监控的PAHS的污染状况进行了调查,采用菲/蒽、荧蒽/芘、荧蒽/(荧蒽+芘)、吲哚芘/(吲哚芘+苯并(g,H,I)苝)等特定比值对PAHS来源进行了分析.结果表明,南黄海表层沉积物中检出PAHS的总含量为90.4~732.65ng·g-1,各站点均以4~6环为主;与其它站位相比,倾废区的H01站位受到PAHS污染较为明显,无论是16种PAHS总量还是高分子量组分最高值都出现在该站点,虽然该海区沉积物中PAHS的含量没有超出生物影响低值,但苯并(b)荧蒽、吲哚芘和苯并(g,H,I)芘等一些没有最低安全标准的PAHS也有不同程度的检出,对海洋生物具有潜在的毒副作用.PAHS可能来源于原油、生物和煤燃烧造成的污染.The concentrations of sixteen representative Polycyclic Aromatic Hydrocarbons(PAHs) in surface sediment samples collected from the Southern Yellow Sea were determined by GC-MS.The distribution and potential sources of PAH contamination in the region were investigated.The types of PAHs found in the surface sediments were mainly 4～6 ring PAHs,and they are unevenly distributed among the different sampling sites covering an area of 139 km2.The area is known for continuous waste dumping activities in recent years,and indeed sites adjacent to such activities were found to have high levels of PAHs.Some high molecular weight PAH compounds such as benzo$$b$$fluoranthene,dibenzo$$a,h$$anthracene and benzo$$g,h,i$$perylene were detected in some samples.The health implication of these contaminants needs careful assessment since toxicity guidelines are not available for these species.The potential sources of PAHs are discussed using various source-specific PAH indexes such as Phenathrene/Anthracene、Fluoranthene/Pyrene、Fluoranthene/(Fluoranthene+Pyrene) and Indeno [1,2,3-cd] pyrene/(Indeno[1,2,3-cd] pyrene+Benzo [g,h,i] perylene).The composition of the observed PAHs reflects that they originate from both petroleum utilization and incomplete combustion.海洋公益性行业科研专项(No.200705011);中国海监技术支撑体系项目;2008年海洋环境保护及节能减排专项---

300kg/a规模流化床制碳纳米管中试研究

采用Ni-Mg-O复合氧化物催化剂进行了流化床甲烷催化裂解法制碳纳米管的中试实验,研究了主要操作变量对甲烷转化率、催化剂产碳率、产品团聚率及催化剂损失率的影响,得到了适宜的操作条件为:甲烷进气流速16～19 cm/s、催化剂粒径150～220μm、催化剂加入量50～60 g、反应温度650～700℃、反应时间120～140 min。多批次重复性实验表明,在选定的操作条件下,甲烷转化率约为30%,催化剂产碳率约为10 gCNTs/gCAT。对纯化后的产品进行SEM及TEM形貌表征显示,制得的碳纳米管管径均匀,中空结构明显,碳纳米管的外径为10～30 nm,内径为2～5 nm。中国海洋石油总公司科技项目(CNOOC-KJ125FZDXM00TJY001-2014

Comparison of Recoveries of PAHs Obtained by Ultrasound-assisted Extraction from Wet and Freeze-dried Marine Sediment

以美国环保局(EPA)优先控制的16种多环芳烃(polycyclic aromatic hydrocarbons,PAHs)为研究对象,建立了湿法超声波辅助萃取技术提取沉积物中痕量PAHs的可靠方法,对萃取剂、萃取功率、萃取次数和萃取时间进行了优化。并与传统干法超声辅助萃取进行了比较,湿法超声波辅助萃取的PAHs回收率为57%～125%,而干法超声波辅助萃取PAHs的回收率为48%～113%,对相对分子质量小的PAHs如萘～芴的回收率,湿法明显高于干法。该文建立的湿法超声辅助萃取适用于沉积物和泥土中痕量PAHs的快速测定。An ultrasound-assisted extraction method for the extraction of 16 trace PAHs(USEPA priority pollutant) from wet(i.e.untreated) marine sediment was developed.The effects of solvent type,power of ultrasound,and extraction time were studied and optimized.The developed method was compared with the traditional ultrasound-assisted extraction for freeze-dried sediment.The results showed that recoveries of sixteen PAHs extracted from the wet marine sediment ranged from 57% to 125%,whereas those extracted from the freeze-dried marine sediment ranged from 48% to 113%.The results also indicated that the recoveries of PAHs with smaller relative molecular mass(e.g.naphthalene and fluorine) extracted from the wet sediment were higher than those from the freeze-dried sediment.Thus the developed method was appropriate for rapid determination of trace PAHs in marine sediment and soil.海洋公益性行业科研专项(200705011);; 中国海监技术支撑体系项目;; 2008年海洋环境保护及节能减排专