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北大别的多阶段高温变质作用与部分熔融及其地球动力学过程和大地构造意义 被引量:5
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作者 刘贻灿 邓亮鹏 +2 位作者 古晓锋 Groppo C Rolfo F 《地质科学》 CAS CSCD 北大核心 2014年第2期355-367,共13页
北大别经历了三叠纪高温超高压变质作用和多阶段折返历史,因而榴辉岩中广泛发育多期减压结构,极少保留早期的超高压变质记录,这为它们不同变质阶段的温度条件估算带来了巨大困难。然而,目前流行的微量元素温度计为北大别榴辉岩的峰期及... 北大别经历了三叠纪高温超高压变质作用和多阶段折返历史,因而榴辉岩中广泛发育多期减压结构,极少保留早期的超高压变质记录,这为它们不同变质阶段的温度条件估算带来了巨大困难。然而,目前流行的微量元素温度计为北大别榴辉岩的峰期及之后的退变质阶段温度的确定提供了可能性。根据锆石中Ti和金红石中Zr温度计,结合传统矿物对温度计的计算数据,获得了北大别榴辉岩中多阶段高温(>900℃)条件的数据,证明研究区经历了从超高压榴辉岩相→石英榴辉岩相→高压麻粒岩相阶段的高温变质过程。并且,北大别经历了折返初期(207±4Ma)的减压熔融和碰撞后燕山期(约130Ma)的加热熔融作用。长时间的高温变质作用与多期部分熔融也许正是北大别长期难以发现柯石英和有关超高压变质证据等的重要原因。因此,这些成果有助于甄别北大别的岩石成因和演化过程以及大别山多岩片差异折返模型的建立和完善。 展开更多
关键词 高温变质作用 部分熔融 大陆碰撞 多阶段折返 北大别
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γ-羟丁酸诱发的大鼠失神性癫痫持续发作诱导丘脑Fos癌蛋白表达 被引量:4
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作者 张遐 鞠躬 +1 位作者 刘惠玲 G.LeGalLaSalle 《解剖学报》 CAS CSCD 北大核心 1993年第1期30-33,T004,共5页
用Fos抗体免疫组织化学法在γ-羟丁酸诱发的大鼠失神性癫痫持续发作模型上,对丘脑Fos癌蛋白表达的分布进行了研究。失神性癫痫发作后30min,双侧丘脑室旁核内可见到少量Fos免疫阳性细胞核;1h时,Fos的大量双侧标记分布于外侧缰核、室旁核... 用Fos抗体免疫组织化学法在γ-羟丁酸诱发的大鼠失神性癫痫持续发作模型上,对丘脑Fos癌蛋白表达的分布进行了研究。失神性癫痫发作后30min,双侧丘脑室旁核内可见到少量Fos免疫阳性细胞核;1h时,Fos的大量双侧标记分布于外侧缰核、室旁核、菱形核和丘脑板内核群。提示外侧缰核及丘脑中线和板内核群极可能涉及失神性癫痫发作的病理生理机制。 展开更多
关键词 癫痫 羟丁酸 丘脑 癌基因
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绿色杜氏藻被膜泡囊的超微结构研究 被引量:3
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作者 黄晓航 张小庆 +1 位作者 吴超元 AlfsenAnnette 《海洋与湖沼》 CAS CSCD 北大核心 1998年第6期565-569,共5页
于1990年5月—1991年5月,运用透射电镜观察绿色杜氏藻,对该藻被膜泡囊的形态结构及其在细胞内的分布和形成过程进行研究。观察表明,绿色杜氏藻细胞的高尔基体和细胞膜附近有许多大小不等的被膜泡囊;这些被膜泡囊由泡囊及其表面的网... 于1990年5月—1991年5月,运用透射电镜观察绿色杜氏藻,对该藻被膜泡囊的形态结构及其在细胞内的分布和形成过程进行研究。观察表明,绿色杜氏藻细胞的高尔基体和细胞膜附近有许多大小不等的被膜泡囊;这些被膜泡囊由泡囊及其表面的网状结构构成,其直径在45—120nm之间;在细胞膜附近的被膜泡囊直径较大;在高尔基体和细胞膜上还观察到被膜泡囊的形成过程。结果提示:在处于指数生长期的绿色杜氏藻细胞中,被膜泡囊起着细胞内大分子物质运输的作用。 展开更多
关键词 绿色杜氏藻 被膜泡囊 藻类 电镜 超微结构
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一种含SiO_2氧化物玻璃的晶化温度-压力依赖关系
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作者 沈中毅 陈立泉 +4 位作者 张云 殷岫君 刘勇 王超英 Cros.C. 《高压物理学报》 CAS CSCD 北大核心 1990年第4期254-258,共5页
本文应用DTA及X射线衍射法在常压及高压下对—种含SiO_2的锂离子导体玻璃0.3Li_2O-0.67SiO_2-0.03V_2O_5加热时的晶化行为进行了研究。该氧化物玻璃的晶化过程分两个阶段。在常压下,第一晶化过程发生在560℃ 附近,析出相为Li_2O·2S... 本文应用DTA及X射线衍射法在常压及高压下对—种含SiO_2的锂离子导体玻璃0.3Li_2O-0.67SiO_2-0.03V_2O_5加热时的晶化行为进行了研究。该氧化物玻璃的晶化过程分两个阶段。在常压下,第一晶化过程发生在560℃ 附近,析出相为Li_2O·2SiO_2。对应的晶化温度T_(x1)随压力的升高发生了急剧的变化。从常压到0.3GPa,T_(x1)从560℃升高到620℃;继续升压时T_(x1)突然下降,并在0.4GPa处跌到528℃,呈现一个陡削的峰值。0.4GPa以上,T_(x1)随压力的变化则呈常规行为,比较平稳地、大致线性地升高,一直到最高测定压力2GPa。本文最后对这些行为的可能原因进行了讨论。 展开更多
关键词 SIO2 玻璃 晶化 温度 压力
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Er离子注入GaP,GaAs,InP的二次离子质谱(SIMS)的研究
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作者 陈辰嘉 王学忠 +5 位作者 周必忠 陈世帛 雷红兵 李仪 李菊生 BottazziP 《发光快报》 EI CAS CSCD 1994年第1期71-73,共3页
近年来掺稀土元素的Ⅲ—V族化合物研究在基础物理和器件应用方面都越来越引起人们的关注,其中又由于Er<sup>3+</sup>的<sup>4</sup>I<sub>13/2</sub>—4<sup>I</sup>——(15/2)的特... 近年来掺稀土元素的Ⅲ—V族化合物研究在基础物理和器件应用方面都越来越引起人们的关注,其中又由于Er<sup>3+</sup>的<sup>4</sup>I<sub>13/2</sub>—4<sup>I</sup>——(15/2)的特征发光波长为1.54μm,恰好对应于石英光纤的低损耗区,且离子注入技术简单易行,因而倍受重视.国际上已报道了不少有关Er注入Ⅲ—V族化合物的研究,大多选用较低的注入剂量(约10<sup>12</sup>~10<sup>14</sup>Er/cm<sup>2</sup>),而对较高剂量的注入有待于进一步研究. 展开更多
关键词 离子注入 二次离子质谱 砷化镓
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土壤中水溶性有机物质的数量、性质及其变化 被引量:8
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作者 丁昌璞 Ceccanti B. 《土壤学报》 1987年第3期210-217,共8页
水溶性有机物质的数量可因绿肥种类、土壤和时间而异。该物质是一类分子量低、带不同电荷(正、负电荷)和等电点的物质,并含有羧基和胺基。其中的某些性质随时间而变。该物质的数量与Eh的相关系数显著。其还原性因绿肥种类而异。工作中... 水溶性有机物质的数量可因绿肥种类、土壤和时间而异。该物质是一类分子量低、带不同电荷(正、负电荷)和等电点的物质,并含有羧基和胺基。其中的某些性质随时间而变。该物质的数量与Eh的相关系数显著。其还原性因绿肥种类而异。工作中应用了凝胶层析、红外、可见光谱分析和等电聚焦技术。 展开更多
关键词 水溶性有机物质 绿肥 分子量 土壤
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南海西南次海盆构造特征及其沉积响应 被引量:2
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作者 聂鑫 邱燕 +3 位作者 Manuel Pubellier 汪俊 朱荣伟 杜文波 《中国地质》 CAS CSCD 北大核心 2020年第5期1463-1473,共11页
本文对穿过南海西南次海盆的逾1000 km的多道地震测线CFT剖面进行了地震界面特征的识别和地震层序的划分,分段分析了拆离断层对其减薄陆壳的拆离作用。结合前人研究成果,对南海西南次海盆地壳结构特征开展了分析,并总结了其构造特征。... 本文对穿过南海西南次海盆的逾1000 km的多道地震测线CFT剖面进行了地震界面特征的识别和地震层序的划分,分段分析了拆离断层对其减薄陆壳的拆离作用。结合前人研究成果,对南海西南次海盆地壳结构特征开展了分析,并总结了其构造特征。西南次海盆在发生陆缘张裂—海盆扩张、洋壳出现—扩张后稳定沉积这一系列过程中,可划分为4个阶段的沉积响应:A阶段(古新世之前)——前裂谷阶段,表现为地壳在拉张应力下产生小的断层;B阶段(始新世—早渐新世)——陆缘的裂谷阶段,地壳在拉张应力下拉张减薄,A阶段产生的断层出现了旋转,出现了大型掀斜的拆离断层,沉积物为同裂谷沉积,该阶段以产生了破裂不整合结束;C阶段(晚渐新世—早中新世)——海盆扩张阶段,海盆开始扩张,张应力从陆缘转移到了洋盆;D阶段(中中新世以来)——海盆扩张结束以后,以一套稳定沉积为特征。 展开更多
关键词 CFT剖面 破裂不整合 洋盆扩张 沉积响应 西南次海盆 海洋地质调查 南海
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Interleukin-6 and its soluble receptor in patients with liver cirrhosis and hepatocellular carcinoma 被引量:25
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作者 Soresi Maurizio Giannitrapani Lydia +6 位作者 D'Antona Fabio Florena Ada Maria La Spada Emanuele Terranova Angela Cervello Melchiorre D'Alessandro Natale Montalto Giuseppe 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第16期2563-2568,共6页
AIM: To evaluate the immunohistochemical localization of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) on tumor tissue specimens from patients with hepatocellular carcinoma (HCC) and the serum levels of IL-6 a... AIM: To evaluate the immunohistochemical localization of interleukin-6 (IL-6) and IL-6 receptor (IL-6R) on tumor tissue specimens from patients with hepatocellular carcinoma (HCC) and the serum levels of IL-6 and sIL-6R in a group of patients with HCC as well as liver cirrhosis (LC) in a group of patients with LC alone and in a control group. METHODS: Three groups of subjects were studied: group Ⅰ (n =83) suffering from HCC and LC, group Ⅱ (n = 72) suffering from LC alone and group Ⅲ (n =42) as healthy controls. All patients had hepatitis C virus infection. Serum IL-6 and IL-6R levels were determined using a commercially available ELISA kit. Immunohistochemistry was performed using the streptavidin-biotin complex and rabbit polyclonal antibodies against IL-6 and IL-6R. RESULTS: Immunohistochemistry analysis showed a medium to strong cytoplasmic and membrane reactivity for IL-6 and IL-6R respectively, in at least 40% of cases of HCC, whereas liver cirrhosis patients and controls were negative for IL-6 or showed a very mild and focal dot-like cytoplasmic reaction for IL-6R. Serum IL-6 levels in HCC group were significantly higher than those in LC and control groups (P〈 0.0001). There was no significant difference in sIL-6R concentrations among 3 groups. When the patients with HCC were divided into groups according to Okuda's classification, a significant serum increase of IL-6 and slL-6R level was observed from stage Ⅰ to stage Ⅲ (P〈0.02, P〈0.0005). When HCC and LC patients were divided into 3 classes of cirrhosis severity according to Child-Pugh, values in HCC patients were significantly higher than those in LC patients for each corresponding class (P〈 0.01). CONCLUSION: IL-6 serum levels in HCC patients are higher than those in LC patients and controls, suggesting an increased production of this cytokine by neoplastic cells, sIL-6R values are similar in all groups, increasing only in stage III HCC patients. These data suggest that they have a closer relationship with the neoplastic mass rather than with the residual functioning hepatic mass. 展开更多
关键词 INTERLEUKIN-6 CYTOKINE Chronic liver disease IMMUNOHISTOCHEMISTRY
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One pot synthesis of TiO_2:Eu^(3+) hierarchical structures as a highly specific luminescent sensing probe for the visualization of latent fingerprints 被引量:7
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作者 K.R.Venkatesha Babu C.G.Renuka +2 位作者 R.B.Basavaraj G.P.Darshan H.Nagabhushana 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第2期134-144,共11页
In the present work, TiO2:Eu^(3+) (1 mol%e11 mol%) nano powders(NPs) were prepared via a facile one-pot hydrothermal method by using Epigallocatechin Gallate(EGCG) as bio-surfactant. The optimized TiO2:Eu^(3+) (5 mol%... In the present work, TiO2:Eu^(3+) (1 mol%e11 mol%) nano powders(NPs) were prepared via a facile one-pot hydrothermal method by using Epigallocatechin Gallate(EGCG) as bio-surfactant. The optimized TiO2:Eu^(3+) (5 mol%) NPs can be used as fluorescent labeling agent for visualizing of latent fingerprints(LFPs) on various porous and non-porous surfaces. The obtained results exhibit well defined ridge details with high sensitivity, selectivity, and low background hindrance which show greater advantages as compared to conventional powders. We demonstrated the viability of high-performance security labels thorough excellent luminescence for practical anti-mimetic applications. Morphology of the prepared samples is highly dependent on pH, concentration of the bio-surfactant, temperature and time durations.Photoluminescence(PL) emission spectra exhibit intense red emission at ~ 615 nm due to electric dipole transition(~5 D_0/~7 F_2). Photometric(CIE and CCT) results clearly show the intense warm red emission of the optimized samples. Therefore, this work offers a superior and universal luminescent label, which can be applied to visualize miniature LFPs particulars for individualization and consequently display great prospective in forensic investigation. 展开更多
关键词 Nano POWDER PHOTOLUMINESCENCE LATENT FINGERPRINTS Bio-surfactant RARE earths
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Partial melting of ultrahigh-pressure metamorphic rocks at convergent continental margins: Evidences, melt compositions and physical effects 被引量:6
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作者 Liang-Peng Deng Yi-Can Liu +2 位作者 Xiao-Feng Gu Chiara Groppo Franco Rolfo 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第4期1229-1242,共14页
Ultrahigh-pressure(UHP) metamorphic rocks are distinctive products of crustal deep subduction,and are mainly exposed in continental subduction-collision terranes. UHP slices of continental crust are usually involved... Ultrahigh-pressure(UHP) metamorphic rocks are distinctive products of crustal deep subduction,and are mainly exposed in continental subduction-collision terranes. UHP slices of continental crust are usually involved in multistage exhumation and partial melting, which has obvious influence on the rheological features of the rocks, and thus significantly affect the dynamic behavior of subducted slices. Moreover,partial melting of UHP rocks have significant influence on element mobility and related isotope behavior within continental subduction zones, which is in turn crucial to chemical differentiation of the continental crust and to crust-mantle interaction.Partial melting can occur before, during or after the peak metamorphism of UHP rocks. Post-peak decompression melting has been better constrained by remelting experiments; however, because of multiple stages of decompression, retrogression and deformation, evidence of former melts in UHP rocks is often erased. Field evidence is among the most reliable criteria to infer partial melting. Glass and nanogranitoid inclusions are generally considered conclusive petrographic evidence. The residual assemblages after melt extraction are also significant to indicate partial melting in some cases. Besides field and petrographic evidence, bulk-rock and zircon trace-element geochemical features are also effective tools for recognizing partial melting of UHP rocks. Phase equilibrium modeling is an important petrological tool that is becoming more and more popular in P-T estimation of the evolution of metamorphic rocks; by taking into account the activity model of silicate melt, it can predict when partial melting occurred if the P-T path of a given rock is provided.UHP silicate melt is commonly leucogranitic and peraluminous in composition with high SiO_2,low MgO, FeO, MnO, TiO_2 and CaO, and variable K_2 O and Na_2 O contents. Mineralogy of nanogranites found in UHP rocks mainly consists of plagioclase + K-feldspar + quartz, plagioclase being commonly albite-rich.Trace element pattern of the melt is characterized by significant enrichment of large ion lithophile elements(LILE), depletion of heavy rare earth elements(HREE) and high field strength elements(HFSE),indicating garnet and rutile stability in the residual assemblage. In eclogites, significant Mg-isotope fractionation occurs between garnet and phengite; therefore, Mg isotopes may become an effective indicator for partial melting of eclogites. 展开更多
关键词 Partial melting Continental subduction-collision Ultrahigh-pressure metamorphism Leucosome Phase equilibrium modeling
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Rapid visualization of latent fingerprints using novel CaSiO_3:Sm^(3+) nanophosphors fabricated via ultrasound route 被引量:4
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作者 R.B.Basavaraj G.P.Darshan +2 位作者 B.Daruka Prasad S.C.Sharma H.Nagabhushana 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第1期32-44,M0003,共14页
Latent fingerprints (LFPs) were the most significant identification method for individualization. Most commonly available fingerprints (FPs) in crime spot investigation were latent and patent types. Generally,LFPs wer... Latent fingerprints (LFPs) were the most significant identification method for individualization. Most commonly available fingerprints (FPs) in crime spot investigation were latent and patent types. Generally,LFPs were invisible and thus the effective visualization technique necessitates for the analysis of such FPs. In the past years, many traditional visualization techniques have been employed, but suffered with low resolution, sensitivity, contrast and high background noise. To overcome such limitations, we synthesized Sm^(3+) doped CaSiO_3 nanophosphors (NPs) via an ultrasound irradiation route using mimosa pudica (m. p.)leaves extract as a bio-surfactant. The morphological behavior of the prepared samples was extensively studied by varying the concentration of the m. p. extract, ultrasound irradiation duration, pH level of the precursor solution and sonication power. The photoluminescence (PL) emission spectra exhibit characteristic peaks at~561,601 and 647 nm, which were attributed to^5G_(5/2)→~6H_J(J=5/2,7/2 and 9/2) transitions of Sm^(3+) ions.The Judd-Ofelt(J-O) intensity parameters and other radiative properties were estimated using PL data. The Commission International de I'Eclairage (CIE) color coordinates were positioned in orange-red region shows average correlated color temperature (CCT) value of~3576 K. The optimized samples can be used as a labeling agent for the visualization of LFPs on various porous and non-porous surfaces under normal light irradiation. The visualized FPs reveals well defined ridge characteristics, namely whorl, loop,arch, bifurcation, eye, island, bridge, sweat pores, etc, with high sensitivity, selectivity, low contrast and background hindrance. Aforementioned results evidence that the prepared CaSiO_3:Sm^(3+) NPs were promising luminescent materials for solid state lighting and forensic applications. 展开更多
关键词 Ultrasonication synthesis Photoluminescence FINGERPRINT PHOTOMETRIC properties Judd-Ofelt analysis RARE earths
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Comparative study of Eu^(3+)-activated LnOCl(Ln=La and Gd) phosphors and their Judd-Ofelt analysis 被引量:4
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作者 N.Dhananjaya C.Shivakumara +2 位作者 Rohit Saraf Sukanti Behera H.Nagabhushana 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第9期946-953,共8页
Eu3+-activated layered LnOCI (Ln=La and Gd) phosphors were synthesized by the conventional solid-state method at relatively low temperature (700 ℃) and shorter duration of 2 h. The structural parameters were ref... Eu3+-activated layered LnOCI (Ln=La and Gd) phosphors were synthesized by the conventional solid-state method at relatively low temperature (700 ℃) and shorter duration of 2 h. The structural parameters were refined by the Rietveld refinement analysis and confirmed by the high resolution transmission electron microscopy (HRTEM). Both the compounds were crystallized in the tetragonal structure with space group P4/nmm (No. 129). The homogeneity of the elements were ana- lyzed by TEM mapping and found to be uniformly distributed. The photoluminescence spectra revealed that the intensity of 5D0--7F2 transition (619 nm) was more intense in Eu3+-activated GdOC1 compared to LaOC1. This was due to the property of Gd3+ ions to act as an intermediate sublattice to facilitate the energy transfer to Eu3+ ions. Intensity parameters and radiative properties such as transition probabilities, radiative lifetime and branching ratio were calculated using the Judd-Ofelt theory. The CIE color coordinates result revealed that the Eu3+-activated GdOC1 (0.641, 0.354) phosphor was close to the commercial red phosphors like, Y203:Eu3+ (0.645, 0.347), Y202S:Eu3+ (0.647, 0.343) and National Television System Committee (NTSC) (0.67, 0.33). The results suggest that the present GdOCI:Eu3+ compound acts as a potential candidate for red phosphor materials. 展开更多
关键词 LaOC1 GdOC1 PHOSPHORS Judd-Ofelt CIE rare earths
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Flux blended synthesis of novel Y2O3:Eu^3+ sensing arrays for highly sensitive dual mode detection of LFPs on versatile surfaces 被引量:7
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作者 K.N. Venkatachalaiah H. Nagabhushana +3 位作者 R.B. Basavaj G.R Darshan B. Daruka Prasad S.C. Sharma 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第9期954-964,共11页
In the present communication,various fluxes blended Y2 O3:Eu3+(5 mol%) nanopowders(NPs) were successfully fabricated by solution combustion method.PXRD pattern confirms body-centered cubic structure of the prepa... In the present communication,various fluxes blended Y2 O3:Eu3+(5 mol%) nanopowders(NPs) were successfully fabricated by solution combustion method.PXRD pattern confirms body-centered cubic structure of the prepared samples.Energy band gap(Eg) of the fabricated products was estimated and is found to be in the range of 3.13-3.32 eV.Photoluminescence(PL) emission spectra exhibit sharp and intense peaks at ~579,592,614,657,704 nm corresponding to 5 D0→7 FJ(J = 0,1,2,3 and 4) transitions of Eu3+ ions.Significance of fluxes for enhancing the PL emissions was extensively studied.Photometric studies of the prepared samples are located in pure red region.Optimized NPs were explored as a novel sensing agent for visualization of latent fingerprints(LFPs) on various surfaces including porous,semiporous and non-porous surfaces followed by powder dusting technique.Various experiments including aging,temperature,scratching and aquatic fresh water treatment tests were performed to evaluate applicability of the fabricated NPs.Visualized LFPs exhibit well defined ridge details including most authenticated sweat pores are also revealed with high sensitivity,selectivity,little background hindrance and less toxicity.Aforementioned results evidence that the method and fabricated NPs can be considered to be simple,rapid and economical and provide novel sensing platform for LFPs visualization in prospective forensic applications. 展开更多
关键词 FLUXES PHOTOLUMINESCENCE Latent fingerprint Sweat pores Forensic applications Rare earths
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Rational design of monovalent ions (Li,Na,K) co-doped ZnAl2O4:Eu3+ nanocrystals enabling versatile robust latent fingerprint visualization 被引量:3
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作者 F.Femila Komahal H.Nagabhushana +4 位作者 R.B.Basavaraj G.P.Darshan Hajeebaba K.Inamdar S.C.Sharma B.Daruka Prasad 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第7期699-705,共7页
Alkali metal ions(M+ = Na+,Li+,K+) co-doped ZnAl2O4:Eu3+(5 mol%)(ZAE) nanopowders(NPs) were prepared via solution combustion route using Mimosa pudica(MP) leaves extract as a fuel. PXRD results of co-doped samples enh... Alkali metal ions(M+ = Na+,Li+,K+) co-doped ZnAl2O4:Eu3+(5 mol%)(ZAE) nanopowders(NPs) were prepared via solution combustion route using Mimosa pudica(MP) leaves extract as a fuel. PXRD results of co-doped samples enhance the crystallinity and grain growth. Photoluminescence(PL) of the prepared ZAE and ZAE:M+(M+ = Na+, Li+, K+) NPs shows intense emission peaks in the range of 550-750 nm and ascribed to 5D0→7FJ(J=0-4) transitions of Eu3+ ions, respectively. A 2-fold enhancement in PL intensity was observed in Li+ co-doped samples. The optimized ZnAl2O4:Eu3+(5 mol%), Li+(1 wt%)(ZAEL)NPs were used to visualize LFPs on various porous, semi-porous and non-porous surfaces through robust powder dusting technique. The visualized latent fingerprints(LFPs) reveal well defined level 1-3 ridge characteristics under several tests such as fingerprint aging and fresh water treatment for various time durations. The obtained results clearly evidence that the prepared NPs are quite useful for multifunctional applications such as advanced forensic and solid state lightning. 展开更多
关键词 Photoluminescence LATENT FINGERPRINTS Solid state lightning Alkali metal IONS Rare earths
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Complexity analysis of blast-induced vibrations in underground mining: A case study 被引量:4
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作者 Cardu Marilena Dompieri Mauricio Seccatore Jacopo 《International Journal of Mining Science and Technology》 SCIE EI 2012年第1期125-131,共7页
Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process par... Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well. 展开更多
关键词 Drilling and blasting Complexity analysis Vibrations control
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胆汁酸及其丁二酸衍生物的快速原子轰击质谱 被引量:1
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作者 达世禄 D.Fraisse 《高等学校化学学报》 SCIE EI CAS 1985年第4期325-329,共5页
本文研究游离胆汁酸及其丁二酸衍生物的快速原子轰击(FAB)质谱.用甘油或硫甘醇作样品的基质,具有不同的灵敏度增强效应。FAB负离子质谱,获得[M-n]^(-)典型离子簇,[M-1]^(-)作为最强离子是每一个样品的基峰.
关键词 丁二酸 离子簇 负离子质谱 胆汁酸 灵敏度增强 衍生物
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THE MAXIMUM AND MINIMUM DEGREES OF RANDOM BIPARTITE MULTIGRAPHS 被引量:1
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作者 陈爱莲 张福基 李皓 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1155-1166,共12页
In this paper the authors generalize the classic random bipartite graph model, and define a model of the random bipartite multigraphs as follows:let m = m(n) be a positive integer-valued function on n and ζ(n,m;{... In this paper the authors generalize the classic random bipartite graph model, and define a model of the random bipartite multigraphs as follows:let m = m(n) be a positive integer-valued function on n and ζ(n,m;{pk}) the probability space consisting of all the labeled bipartite multigraphs with two vertex sets A ={a_1,a_2,...,a_n} and B = {b_1,b_2,...,b_m}, in which the numbers t_(ai),b_j of the edges between any two vertices a_i∈A and b_j∈ B are identically distributed independent random variables with distribution P{t_(ai),b_j=k}=pk,k=0,1,2,...,where pk ≥0 and ∞Σk=0 pk=1. They obtain that X_(c,d,A), the number of vertices in A with degree between c and d of G_(n,m)∈ζ(n, m;{pk}) has asymptotically Poisson distribution, and answer the following two questions about the space ζ(n,m;{pk}) with {pk} having geometric distribution, binomial distribution and Poisson distribution, respectively. Under which condition for {pk} can there be a function D(n) such that almost every random multigraph G_(n,m)∈ζ(n,m;{pk}) has maximum degree D(n)in A? under which condition for {pk} has almost every multigraph G(n,m)∈ζ(n,m;{pk}) a unique vertex of maximum degree in A? 展开更多
关键词 maximum degree minimum degree degree distribution random bipartite multigraphs
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Contrast enhanced multi-detector CT and MR findings of a well-differentiated pancreatic vipoma 被引量:1
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作者 Luigi Camera Rosa Severino +5 位作者 Antongiulio Faggiano Stefania Masone Gelsomina Mansueto Simone Maurea Rosa Fonti Marco Salvatore 《World Journal of Radiology》 CAS 2014年第10期840-845,共6页
Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not speci... Pancreatic vipoma is an extremely rare tumor accounting for less than 2% of endocrine pancreatic neoplasms with a reported incidence of 0.1-0.6 per million. While cross-sectional imaging findings are usually not specific, exact localization of the tumor by means of either computed tomography(CT) or magnetic resonance(MR) is pivotal for surgical planning. However, cross-sectional imaging findings are usually not specific and further characterization of the tumor may only be achieved bysomatostatin-receptor scintigraphy(SRS). We report the case of a 70 years old female with a two years history of watery diarrhoea who was found to have a solid, inhomogeneously enhancing lesion at the level of the pancreatic tail at Gadolinium-enhanced MR(Somatom Trio 3T, Siemens, Germany). The tumor had been prospectively overlooked at a contrast-enhanced multi-detector CT(Aquilion 64, Toshiba, Japan) performed after i.v. bolus injection of only 100 cc of iodinated non ionic contrast media because of a chronic renal failure(3.4 mg/mL) but it was subsequently confirmed by SRS. The patient first underwent a successful symptomatic treatment with somatostatin analogues and was then submitted to a distal pancreasectomy with splenectomy to remove a capsulated whitish tumor which turned out to be a well-differentiated vipoma at histological and immuno-histochemical analysis. 展开更多
关键词 PANCREATIC endocrine tumor Vasoactive intestinal peptide Multi-detector computed tomography CONTRAST induced nephropathy Magnetic resonance imaging Nephrogenic systemic fibrosis SOMATOSTATIN receptor SCINTIGRAPHY
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填充剂的表面处理及其对弹性体的补强作用
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作者 J.B.Donnet E.Papirer 郑倩瑜 《合成橡胶工业》 CAS CSCD 北大核心 1990年第S1期22-25,共4页
近几年我们研究室进行了固体表面改性对填充剂补强能力影响的系统研究。现将由碳氢链接枝改性白炭黑和炭黑,迄今为止的一些结果,加以论述。 本文对填充剂表面的化学改性,提出报告,並通过几种物理化学方法,包括对原始物料和已改性填充剂... 近几年我们研究室进行了固体表面改性对填充剂补强能力影响的系统研究。现将由碳氢链接枝改性白炭黑和炭黑,迄今为止的一些结果,加以论述。 本文对填充剂表面的化学改性,提出报告,並通过几种物理化学方法,包括对原始物料和已改性填充剂的表面自由能的测定,论述所获及材料的特征。此外,还列举某些有关补强行为的实验结果。 展开更多
关键词 白炭黑 弹性体 填充剂 表面处理 补强作用 表面自由能 动态力学性能 固体表面改性 吸附等温线 互作用
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意大利撒丁岛中部Lasasai-Bonucoro地区的废弃露天滑石-绿泥石-长石采矿场的水资源及其修复模式(英文)
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作者 Maddalena FIORI Carlo MATZUZZI 《岩石学报》 SCIE EI CAS CSCD 北大核心 2004年第4期899-906,共8页
在撒丁岛中部Orani地区,一些赋存在古生代变质岩和花岗岩中的滑石-绿泥石-长石矿体一直处于露天开采状态。采矿活动严重破坏了Lasasai-Bonucoro地区的原始景观。露天开矿形成了一些水坑,里面填满了来自含水层的沿断裂渗出水,因此对该地... 在撒丁岛中部Orani地区,一些赋存在古生代变质岩和花岗岩中的滑石-绿泥石-长石矿体一直处于露天开采状态。采矿活动严重破坏了Lasasai-Bonucoro地区的原始景观。露天开矿形成了一些水坑,里面填满了来自含水层的沿断裂渗出水,因此对该地区的重整应被视作是对自然景观的全面修复工程。在本次工作的第一阶段,作者描述了环境和水文地质学特征,以及根据不同整治措施对不同地域进行了划分。随后的工作包括详细地解释不同的整治技术措施。为了使该地区复原,首要措施包括:1)对一些地形崎岖的地点进行平整改造和重新规划。也就是根据前期规划合适的地点,将矿石开采和堆存地中过多的废石搬走并回填到山谷中。2)修复被挪走的土壤植被,并且在完成污水处理之后,通过植被重植的方法(包括:移植土壤和养分、水流播种草本植物,阶段性机械洒水)对新形成的地表进行改造。3)并通过以上重植技术,修复恰当的斜坡以及总体缺乏植被的地表。 以上措施会引起地表高度和地形的微小变化。可是这些措施足以形成一个新的环境条件,可进行新的开采。特定情况下,例如在有恒定的高品质水流,并且环境宜人的乡村,以上建议很容易实施。因而,Lasasai-Boalitynucoro地区的资源的可利用性至少包括以下互不相斥的两个方面:1)休闲胜地,2) 展开更多
关键词 环境 修复 撒丁岛 水资源 露天矿山
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