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铸铁化学镀Ni-P合金稳定剂的研究

铸造技术 2006年第4期27卷 330-332页

作者：雷阿利冯拉俊马小菊连炜西安理工大学材料科学与工程学院陕西西安710048 西安工业学院陕西西安710023

针对化学镀Ni-P合金过程中稳定性差,镍离子消耗量大的实际,以镀速、镀液稳定性、镀层孔隙率和耐蚀性为评价指标,研究了Na2S2O3、Pb(AC)2、稳定剂A及稳定剂b等4种稳定剂在乳酸为络合剂的Ni-P化学镀液中的稳定效果。结果表明:复合稳定剂... 详细信息

针对化学镀Ni-P合金过程中稳定性差,镍离子消耗量大的实际,以镀速、镀液稳定性、镀层孔隙率和耐蚀性为评价指标,研究了Na2S2O3、Pb(AC)2、稳定剂A及稳定剂b等4种稳定剂在乳酸为络合剂的Ni-P化学镀液中的稳定效果。结果表明:复合稳定剂比单一稳定剂镀速高、稳定性好、孔隙率低。其中以Pb(AC)2与稳定剂A组合时镀液和镀层性能最好,稳定性达到35 000 s,镀速为30.1μm/h,孔隙率为0.78个/cm2,耐盐雾腐蚀为856 h。

关键词：化学镀稳定剂乳酸

Progress and recent trend in MILD combustion

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Science China(Technological Sciences) 2011年第2期54卷 255-269页

作者： LI PengFei MI JianChun DALLY b b WANG FeiFei WANG Lin LIU ZhaoHui CHEN Sheng ZHENG ChuGuang State Key laboratory of Turbulence and Complex Systems Peking University Beijing 100871 China School of Mechanical Engineering University of Adelaide South Australia 5005 Australia State Key laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 China

Moderate or intense low oxygen dilution(MILD)combustion plays a significant role in the mitigation of combustion-generated pollutants and greenhouse gases whilst meeting thermal efficiency ***,due to the lack of the fundamental knowledge on this combustion,there is a misconception that MILD combustion should be established by high preheating of the air,which has limited its *** research and development on this combustion has been performed for several years. We have found that the requirements for establishing the MILD combustion are more relaxed than *** is also revealed that this combustion of different type,i.e.,non-premixed,partially premixed and fully premixed,can be achieved by firing various fuels(i.e.,gaseous,liquid and solid fuels).It is suggested that the application of the MILD combustion can be expanded *** present review summarizes the progress and recent trend made in the R&D of this combustion and recommends further fundamental studies for improving our knowledge and widening its applications.

关键词： high temperature air combustion flameless oxidation flameless combustion oxy-fuel combustion

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Prevalence of diverticulosis in recurrent Clostridium difficile infection

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World Journal of Gastroenterology 2010年第3期16卷 345-347页

作者： Michael J Lipp Odelya E Pagovich David Rabin Albert D Min brett b bernstein Division of Digestive Diseases Beth Israel Medical Center Division of Medicine Beth Israel Medical Center

AIM:To re-evaluate the theory that colonic diverticulosis is associated with relapse of Clostridium difficile associated disease (CDAD) in light of data suggesting increasing rates of CDAD infection and ***: Charts were reviewed for patients with recurrent CDAD who had also had a prior colonoscopy or flexible sigmoidoscopy. An age and gender matched control group was used to compare the prevalence of ***: Twenty-two patients met the study criteria, and the prevalence of diverticulosis in patients with CDAD relapse was 23% compared to 32% in age and sex matched controls (P=0.44). A significant proportion of patients with CDAD relapse had comorbidities associated with immune ***: Diverticulosis does not appear to be associated with CDAD relapse.

关键词： Clostridium diff icile Diverticulosis Relapse Immune suppression Clostridium difficile associated disease

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采用室温光具的热红外成象光谱技术(上)

红外 1997年第4期18卷 9-16页

作者： Clayton la baw 高国龙美国加利福尼亚理工大学喷气推进实验室

热红外光谱技术所用的常规法不是通过冷却光谱仪来减少有关波段的背景辐射,就是使用冷光学调制盘,要不然就是两种方法都采用。这些方法均需要进行严密的遮光,而且为了防止探测器观察温暖的周围物体,常常需要使用中继光具,这样便会导致... 详细信息

热红外光谱技术所用的常规法不是通过冷却光谱仪来减少有关波段的背景辐射,就是使用冷光学调制盘,要不然就是两种方法都采用。这些方法均需要进行严密的遮光,而且为了防止探测器观察温暖的周围物体,常常需要使用中继光具,这样便会导致成本、复杂性、重量以及功率增加。现在已发明了一种仅将被测波长的能量成象在一列探测器上的技术。当观察发射热红外辐射的地球时,它可以提供>300的辐射信号/噪声比,而同时又允许使光具和光谱仪保持在局部的环境温度下。采用这种方法,不需要对光学信号进行开关或调制。为了进行必要的背景辐射抑制,在探测器附近安置了一个新研制的可变光谱滤光片。本文介绍了导致研制这种滤光片的理论,讨论了它在实际的光具/探测器组件中的应用。为了论证上述原理的切实可行性,已制造了一台“原理验证”仪器,即热红外成象光谱仪。介绍了该仪器的研制试验计划,同时还提出了一些需要改进的(?)面。

关键词：热红外成象红外光谱室温光具

Assessment of Meteorological Drought in Climate Variability Context within the Comoe River Transboundary Watershed

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Atmospheric and Climate Sciences 2022年第1期12卷 1-17页

作者： Ismaïla Ouattara Léréyaha Coulibaly Koffi Abdelaziz Kouakou Amidou Dao Dabissi Djibril Noufé bamory Kamagaté Issiaka Savané UFR Sciences Géologiques et Minières (SGM) Université de Man Man C&#244 te d’Ivoire Département de Géosciences Université Péléforo Gon Coulibaly (UPGC) Korhogo C&#244 te d’Ivoire laboratoire Géosciences et Environnement (LGE) UFR-SGE Université Nangui Abrogoua (UNA) Abidjan C&#244 te d’Ivoire

In the context of climate variability resulting in a decrease in rainfall with a severe drought, a spatio-temporal study of this phenomenon remains imperative for the efficient management of water resources. This paper aims to assess the long-term rainfall drought trend and breakpoints within the Comoe River watershed. From monthly rainfall data series (1960-2000), Standardized Precipitation Index (SPI) values were calculated for a time scale of 3 months (SPI.3). Statistical tests for breaks (CUSUM, and t-Student) and trends (Man-Kendall and Linear Regression) as well as the Sen’ slope method for estimating the magnitude of trends was applied. The breaks dates observed are mostly located after the 1970s. Based on SPI.3 values below the threshold of 0.84 chosen as an indicator of drought, rarely has more than half of the catchment area been affected by drought. The average watershed affected is about 20% over the study period (1960-2000). The most representative years, in terms of spatial expansion of the drought, in decreasing order of importance are: 1983, 1992, 1972 and 1982. The years 1982 and 1983 stand out for their exceptional condition, as the drought-affected 50% to 90% of the total catchment area. SPI.3 series from 1960 to the various break dates recorded slopes between -0.01 and 0.00 with a slight drought trend for most of the catchment. After the break periods, almost the entire northern part of the basin is characterized by slight moisture with Sen’s slopes between 0.000 and 0.005. The southern part will remain slightly subject to normal rainfall conditions.

关键词： Climate Variability Drought SPI.3-Index Sen’s Slope Comoe River basin

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一个边缘耀斑及其物质抛射的运动

天文研究与技术 2006年第3期3卷 239-246页

作者：钟树华占腊生中国科学院国家天文台云南天文台云南昆明650011

分别对1989年5月8日太阳西南边缘爆发了一个SN级的圆形耀斑部分和柱状物质抛射部分的运动情况进行分析讨论。耀斑圆形直径增大过程的膨胀速度较大,最大为110km/s,时间非常快,从开始产生至膨胀到最大直径15500km仅用了4min时间;减小收缩... 详细信息

分别对1989年5月8日太阳西南边缘爆发了一个SN级的圆形耀斑部分和柱状物质抛射部分的运动情况进行分析讨论。耀斑圆形直径增大过程的膨胀速度较大,最大为110km/s,时间非常快,从开始产生至膨胀到最大直径15500km仅用了4min时间;减小收缩的过程速度缓慢,为-20^-10km/s,时间过程相对长,从最大直径开始减小到完全消失用了17min时间。柱状物质抛射部分的直径从开始膨胀到最大9060km用了7min时间,最大速度为35km/s;收缩过程用了14min时间,收缩速度在-15^-5km/s左右。柱状物质抛射部分的升降速度,在耀斑极大以后的时间仍在上升,并仍以很高的速度向上喷射,到耀斑极大后3min才开始下降。柱状物质抛射部分到达最大高度22000km的时间与其直径膨胀到最大的时间同时,上升的速度100~130km/s,下降的速度在-20^-5km/s,抛射物质下降到16000~15000km的高度缓慢消失。

关键词：太阳耀斑运动

Three-dimensional investigation of velocity skin effect in U-shaped solid armature

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Progress in Natural Science:Materials International 2008年第12期18卷 1565-1569页

作者： Xin Li~a Chunsheng Weng~b a School of Power Engineering,Nanjing University of Science and Technology,Nanjing 210094,China b National Key laboratory of Transient Physics,Nanjing University of Science and Technology,Nanjing 210094,China School of Power Engineering Nanjing University of Science and Technology Nanjing 210094 China National Key laboratory of Transient Physics Nanjing University of Science and Technology Nanjing 210094 China

A three-dimensional transient computational model is applied to investigate the velocity skin effect (VSE) in a U-shaped solid arma- *** this model,current and heat transport in the armature can be evaluated *** results show a local concentration of current and joule heating at the interface,and significant damage occurs at the edges of the *** is also observed that there is significant enhanced heating at sharp comers because of the armature *** three-dimensional model can efficiently capture the salient features of the physical phenomena at the rail-armature interface,and contribute to the development of the armature design.

关键词： Electromagnetic launch Railgun U-shaped armature Velocity skin effect Erosion

The Two Cultures of Science: Implications for University-Industry Relationships in the U.S. Agriculture biotechnology

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Journal of Integrative Agriculture 2014年第2期13卷 455-466页

作者： William b lacy Leland L Glenna Dina biscotti Rick Welsh Kate Clancy University of California State College Pennsylvania State University Syracuse University Johns Hopkins University

Partnerships between U.S. universities and industries have existed for several decades and in recent years have become generally more varied, wider in scope, more aggressive and experimental and higher in public visibility. In addition, in the last few decades, public and private interests have advocated for government policies and laws to globally promote the commercialization of university science. This paper examines the persistence or convergence of the two cultures of science and the implications of this commercialization for university-industry relationships in agriculture biotechnology. The perceptions and values of over 200 U.S. university and industry scientists, managers and administrators who participate in or oversee research collaborations in agricultural biotechnology were analyzed. The findings revealed that the participants in these research relationships continue to perceive very distinct cultures of science and identify a wide range of concerns and disadvantages of these partnerships. Several actions were discussed to ensure that the two cultures serve complementary roles and that they maximize the public benefits from these increasing collaborations.

关键词： two cultures of science agricultural biotechnology university-industry relationships

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藏语依存树库构建的理论与方法探析

西藏大学学报（社会科学版） 2015年第5期30卷 76-83页

作者：扎西加多拉西藏大学藏文信息技术研究中心西藏拉萨850000 西北民族大学中国藏文典籍全文数字化研究所甘肃兰州730030

依存语法又称"从属关系语法",研究句子各构成成分之间的支配和从属关系。依存结构是指句子中词与词之间的句法结构关系,该结构以树状结构进行描述,被称之为依存结构树库。文章以依存语法的理论框架作为藏语树库构建的理论指导,充分借鉴... 详细信息

依存语法又称"从属关系语法",研究句子各构成成分之间的支配和从属关系。依存结构是指句子中词与词之间的句法结构关系,该结构以树状结构进行描述,被称之为依存结构树库。文章以依存语法的理论框架作为藏语树库构建的理论指导,充分借鉴依存语法的思想精髓,结合藏语语法体系,设立出符合藏语语法体系的句法和语义标注关系体系,设计了判别式的句法分析算法,从而构建了多维视窗的藏语依存树库。具体分析时,首先,对依存语法的由来、定义、依存关系的适用性等背景知识做了简要的阐释;其次,在藏语句子的筛选、藏语依存结构的形式化模型、藏语依存的骨架结构以及藏语依存树的多维关系等方面进行了研究和分析。

关键词：依存语法藏语树库藏语句法分析藏语语义分析