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微波合成半导体HgS纳米粒子 总被引：2，自引：3，他引：2
廖学红 《黄冈师范学院学报》2001,21(3):48-51
在甲醛溶液中，以Hg(Ac)2和TAA为原材料，通过微波加热合成了HgS半导体纳米粒子，并用XRD、TEM、紫外光谱进行了表征。 相似文献
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以有机溶剂热生长技术(solvothermal technique)制备了半导体硫族化合物(CdS、ZnS、MoS2)等纳米颗粒,采用XRD、TEM等技术对其结构进行表征.以ITO导电玻璃以及导电聚合物(PANI、PPY)膜为基底,将纳米颗粒涂布其上并以PL法研究其光学特性,实验结果表明:经修饰后,材料的荧光发射位置发生显著的变化. 相似文献
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微波合成半导体CuS纳米粒子和Bi2S3纳米棒 总被引：2，自引：0，他引：2
在甲醛溶液中，以Cu(Ac)2,Bi(NO3)3和TAA为源材料，通过微波加热合成了CuS半导体纳米粒子和Bi2S3纳米棒，并用XRD，TEM进行了表征。 相似文献
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以N a2SeSO3和Zn(A c)2.2H2O为源材料,通过微波辐射加热合成了ZnSe半导体纳米粒子,并用XRD和TEM进行了表征. 相似文献
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Ⅱ-Ⅵ族半导体材料ZnS纳米粒子,具有特殊而优良的可见光区荧光性质使得具有极大应用前景,因而引起人们的广泛关注.文章概述了ZnS的制备方法、发光性能以及表面修饰的研究进展,并对发展进行了展望. 相似文献
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以SnCl4和TAA为Sn源和S源，在盐酸溶液中通过微波辐射加热合成了SnS2半导体纳米粒子，并用XRD、TEM进行了表征。 相似文献
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Alloying is an effective way to manipulate the composition and physico-chemical properties of functional materials. We demonstrated the syntheses of alloyed Co x Ni1?x O nanocrystals using a nonaqueous approach, with x continuously tuned from 0 to 1 by varying the molar ratios of the cobalt precursor in the reagents. The morphological, structural, and compositional properties of the alloyed Co x Ni1?x O nanocrystals were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and energy dispersive X-ray spectroscopy (EDS). The results showed that the cobalt and nickel atoms were homogeneously distributed in the alloyed nanocrystals. The as-prepared Co x Ni1?x O nanocrystals can be applied as the hole-transporting layers in polymer light emitting diodes (PLEDs). Our study provides a good example for the syntheses of alloyed oxide nanocrystals with continuously tunable composition. 相似文献
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张彦群 《安阳师范学院学报》2005,(3):115-119
"到"在现代汉语句法结构中的分布主要有以下几种情况:(1):(S)//D (N),(2):(S)//D N VP,(3):(S)//V D (□),(4):(从)X到Y.在不同的句法结构里,"到"表现为动词、介词、连词、助词等不同的词性."到"的词性不同,与之相应的句法结构也应作不同的分析. 相似文献
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Paul Craddock Jessica S. Wasserman Cody W. Polack Thierry Kosinski Charlotte Renaux Ralph R. Miller 《Learning & behavior》2018,46(2):171-181
Second-order conditioning (SOC; i.e., conditioned responding to S2 as a result of S1–US pairings followed by S2–S1 pairings) is generally explained by either a direct S2→US association or by an associative chain (i.e., S2→S1→US). Previous research found that differences in responses to S2 after S1 was extinguished often depended on the nature of the S2–S1 pairings (i.e., sequential or simultaneous). In two experiments with human participants, we examined the possibility that such differences result from S1 evoking S2 during extinction of S1 following simultaneous but not sequential S2–S1 pairings. This evocation of S2 by S1 following simultaneous pairings may have paired the evoked representation of S2 with absence of the outcome, thereby facilitating mediated extinction of S2. Using sequential S2-S1 pairings, both Experiments 1 and 2 failed to support this account of how extinction of S1 reduced responding to S2. Experiment 1 found that extinguishing S1 reduced responding to S2, while extinguishing S2 had little effect on responses to S1, although forward evocation of S1 during extinction of S2 paired the evoked representation of S1 with absence of the outcome. In Experiment 2, evocation of S2 during S1 nonreinforced trials was prevented because S2–S1 pairings followed (rather than proceeded) S1-alone exposures. Nevertheless, responding to S2 at test mimicked S1 responding. Responding to S2 was high in the context in which S1 had been reinforced and low in the context in which S1 had been nonreinforced. Collectively, these experiments provide additional support for the associative-chain account of SOC. 相似文献
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也说"还NP呢"句式 总被引：1，自引：0，他引：1
丁力 《陕西理工学院学报(社会科学版)》2007,25(3):46-50
对"还NP呢"句式的认识有待进一步深入。目前既已讨论的"还NP呢"句式只是"还NP呢"句式中的一种类型,"还NP呢"句式还包括其他类型。本文主要从语用价值和句法环境两个角度,考察既有的讨论中"还NP呢"句式(本文用S1表示)同另一种"还NP呢"句式(本文用S2表示)所存在的一些重要差异。 相似文献
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OBJECTIVE: To determine the lifetime criminality of men charged with a sexual offence against a child and to identify any heuristic typologies. METHOD: The police files of a 2-year cohort of 462 men charged with a sexual offence against a minor (<17) in two English counties were analyzed; 374 were convicted. The patterns of their convictions produced a typology based upon judicially substantiated parameters. RESULTS: Half the guilty men had prior convictions for non-sexual crimes, including 24% with convictions for violent offences. Three heuristic groups emerged: "Sex-Only" offenders (S.O., n = 186); "Sex And Other" offenders (S.A.O., n = 97); and "Sex and Violent" offenders (S.V., n = 91), averaging three sex convictions each. However, the S.A.O. and S.V. men had more non-sexual than sex convictions, averaging 5.1 versus 10.5, justifying the designation of "multi-criminal" child sex abusers. However, the patterns of these men's sexual offending did not differ, except that the S.O. men's victims were significantly more often intra-family, 36%, 31%, and 13%, respectively; indicating that the majority of these men's victims were extra-familial (71%). Significantly, 19% of the convicted men had at least one "not guilty" verdict for a sex charge, as opposed to 4% for non-sexual crimes. CONCLUSIONS: While the S.O. group appear to consist of traditional types of fixated and regressed offenders, in men charged with offences, they are atypical of most sex abusers since their victims are mainly extra-familial. These "multi-criminal" men present particular challenges for custodial and therapeutic settings, and the potential dangerousness of these offenders should not be underestimated. 相似文献
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According to the temporal-coding hypothesis (TCH; Savastano & Miller, Behavioural Processes 44:147–162, 1998), acquired associations include temporal information concerning the interval between the associated elements. Moreover, the TCH posits that subjects can integrate two independently acquired associations that share a common element (e.g., S2–S1 and S1–US), which results in the creation of a third association with its own temporal relationship (S2–US). Some evidence has suggested that such temporal integration occurs at the time of testing (Molet, Miguez, Cham, & Miller, Journal of Experimental Psychology: Animal Behavior Processes 38:369–380, 2012). Here we report two fear-conditioning experiments with rats conducted to identify the associative structure of the integrated temporal relationship. The goal was to distinguish between two possible associative structures that could exist following an initial test on which temporal integration occurs: (1) Conditioned responding to S2 on subsequent tests could be the result of recurring successive activation of two independently learned temporal maps that remain independently stored in memory (i.e., S2–S1 plus S1–US). (2) Temporal integration at the moment of initial testing could result in the formation of a direct S2–US (or S2–response) temporal map. Integration was found to occur at test and to produce a new association that was independent of associations with the common element (S1). However, the associative status of S1 appeared to modulate whether or not the new association with S2 was US-specific (S2–US) or directly activated a fear response (S2–response). 相似文献
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The Third International Mathematics and Science Study (TIMSS) provides data that seems clearly important to science and mathematics education in the U.S. TIMSS gathered extensive data on curriculum, textbooks, teachers, and instructional practices in science and mathematics education and some of these data are presented and discussed. Eighth grade achievement data show the U.S. to be somewhat above average in science achievement but consistently average or below in mathematics. U.S. official curricula cover comparatively many topics and are relatively unfocused. U.S. science and mathematics textbooks typically take a cautious, inclusive approach keeping traditional content while adding new reform topics. They thus lack. Teachers, without guidance to help them focus, typically divide their attention among many topics. Empirically, there is little agreement in the U.S. on what is truly basic judging by common topics among curricula and textbooks. U.S. teaching, at least in mathematics, is teacher and moves among many different activities, failing to tell a coherent story. We must face these as we seek to find ways to become what we want to be in providing science and mathematics education. 相似文献
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丁力 《陕西理工学院学报(社会科学版)》2002,20(1):26-30,36
本文主要讨论了“还NP呢”（S1）句式与“到底是NP啊”（S2）句式在两种不同思维层面中的同和异;在主观推测层面,S1与S2具有相同的固有推测义;在客观认知层面,S1与S2具有不同的语境认知义。这种不同思维层面的同和异,集中体现了S1与S2这两种不同句式既相互区别,又相互联系。 相似文献