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1.
One-dimensional carbon nano-materials (ODCNMs) synthesized from ethanol flames exhibit various agglomerated morphologies, such as "chrysanthemum-like", "hairball-like" or "orange-peel-like", "vertically aligned" and "wrinkling-pileup". The present work studied the agglomerating process and the growth mechanism by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is thought that the size and distribution of the catalyst particles produced from pretreatment of the substrates play a key role during the formation of agglomerations. It is expected that the steady growth of ODCNMs in flames will be improved through the preparation of the catalysts.  相似文献   

2.
A group of constructed wetlands (CWs) were applied to the recirculating aquaculture system. This study assessed the performance of CWs in treating the aquaculture wastewater, examined the water quality condition of aquaculture ponds and the growth and the survival rate of "target" species (Ictalurus punctatus and Megalobrama amblycephala). The results showed that CWs were effective on reducing the concentrations of 5-day biochemical oxygen demand (BOD5, at 70.5%), total suspended solids (TSS, at 81.9%), chlorophyll a (Chl-a, at 91.9%), ammonium (NH4^+, at 61.5%) and nitrate nitrogen (NOa-N, at 68.0%). Effect of CWs on phosphate (PO43 -P) removal was relatively lower (at 20.0%). The concentrations of BODs, TSS, Chl-a, NH4^+ and TN, TP in the recirculating culture pond were significantly lower than that in the control pond( p〈0.05 ). CWs could help to increase total yield, survival rate of the "target" species and significantly decrease feed conversion ratio ( p〈0.05 ).  相似文献   

3.
2008年5月26-29日,由美国光学学会(Optical Society of America)、中国光学学会、国家自然科学基金委员会、东南大学以及美国Dayton大学(University of Dayton)共同主办,东南大学具体承办的2008年美国光学学会纳光子学专题会议(The OSA Topical Conference on Nanophotonics’2008)在南京隆重召开。来自美国、加拿大、荷兰、意大利、瑞典、英国、澳大利亚、日本、韩国及中国等国家和地区的近250名专家和学者出席了会议,其中海外学者70人。  相似文献   

4.
Rapid growth behavior of ζ phase has been investigated in the undercooling experiments of Cu-14%Ge, Cu-15%Ge, Cu-18.5%Ge and Cu-22%Ge alloys. Alloys of the four compositions obtain the maximum undercoolings of 202 K(0.17TL), 245 K(0.20TL), 223 K(0.20TL) and 176 K(0.17TL), respectively. As the content of Ge increases, the microstructural transition of "a(Cu) dendrite + ζ" peritectic phase → ζ" peritectic phase →, ζ dendrite + (ε+ζ) eutectic" takes place in the alloy at small undercooling, while the microstructural transition of "fragmented α (Cu)dendrite + ζ peritectic phase →, ζ peritectic phase →ζ dendrite + ε phase" happens in the alloy at large undercooling. EDS analysis of the Ge content in peritectic phase indicates that undercooling enlarges the solid solubility of ζ rdendrite, which leads to a decrease in the Ge content in ζ phase as undercooling increases. In the Cu-18.5%Ge alloy composed of ζ peritectic phase, the Ge content in ζ phase increases when undercooling increases, which is due to the restraint of the Ge enrichment on the grain boundaries by high undercooling effect.  相似文献   

5.
第6届光通信和无线通信学术会议暨展览会(APOC2006),于2006年9月3-7日在韩国光州金大中国际会议中心举行。此次会议由国际光学工程学会(SPIE),韩国光学学会、中国光学学会等共同承办,是继美国OFC(Optical Fiber Comtnunications)、欧洲ECOC(European Conference of Optical Communications)之后的全球第三大光通信行业国际会议,自2001年开始,该会议先后在中国的北京、上海、武汉及韩国的光州举行。  相似文献   

6.
In this study, we investigated how the negative emotional arousal induced by watching a number of unpleasant images altered the concentration of secretory immunoglobulin A (SlgA) in saliva. Although our results found discrepancies among participants' SIgA concentration (i.e. some participants' SlgA decreased after watching unpleasant pictures, whereas others increased), further analysis revealed correlations among participants' changes in SIgA concentration, their general coping styles and their actual strategies for emotion regulation when perceiving unpleasant pictures, and the event-related potentials (ERPs) associated with viewing unpleasant pictures. The participants whose SIgA increased after watching unpleasant pictures (the "Increasers") had higher positive coping scores in the Trait Coping Styles Questionnaire (TCSQ) than those whose SIgA decreased (the "Decreasers"). Also, relative to the "Decreasers", the "Increasers" tended to use more emotion regulation strategies, particularly with extremely negative pictures. The amplitude of their late positive potentials (LPPs) exhibited a reverse dissociation pattern for extremely negative pictures versus least negative ones and was related to the cognitive evaluation of the stimuli's meaning. In sum, this research revealed the psychological mechanisms by which negative emotional states influence the immune system and the related ERP changes.  相似文献   

7.
《科学通报(英文版)》2009,(16):2909-2910
A research team from Nanging Institute of Geology and Paleontology, Chinese Academy of Sciences, recently published their research "Supraspecific Taxa of the Bivalvia first named, described, and published in China" (1927--2007) in the University of Kansas Paleontological Contributions New Series 17.  相似文献   

8.
Based on the scanning electron microscope (SEM) observations, it is confirmed that the nacre is composed of aragonite crystals and organic matrix with interlaced arrangement, showing ordered "brick-mortar" structure. The dynamic analysis of preferential orientation of aragonite crystals in the nacre from the abalone (Haliotis diverscolor supertexta) with different shell ages is systematically investigated using X-ray diffraction (XRD) and high resolution transmission electron microscope (HRTEM). Experiments reveal that, in the nacre from the juvenile mollusk shell, there exist three kinds of orientations of aragonite crystals: (113), (002) and (012). However, along with the growing of the mollusk shell, the intensity of (012) and (113) becomes weak, and the (002) becomes the preferred crystal orientation of aragonite in the nacre from the adult mollusk shell, which means that the c axis of aragonite crystals is perpendicular to the nacreous layers. The results obtained show that the nacre possesses a highly ordered structure at the micrometer/nanometer mulUscale levels.  相似文献   

9.
孙一鸥 《科技信息》2010,(27):220-221
本文以文学作品为语料,结合话语分析以及语用学中的理论对话与标记语well进行分析。借助文学作品中搜集的语料,笔者采用了冉永平(2003)提出的"面子威胁行为缓和语"(mitigator of face-threatening acts),"延缓标记语"(hesitation or delay marker),"信息短缺标记语"(insufficiency marker)和"信息修正标记语"(repair marker)的模式对文学作品进行分析,以进一步强调识别文学作品中话语标记语功能的重要性,以及对EFL学习者构建英语思维模式的重要作用。  相似文献   

10.
In the present study, high-density event-related potentials (ERPs) were recorded to examine the electrophysiologic correlates of "Aha!" effects in a guessing Chinese Iogogriph task by using a two-stage model for learning-testing. Results showed that: Firstly Successful Guessing elicited a more negative ERP deflection (N350) than Recognition did in the time window from 300--350 ms after onset of the stimuli. A voltage map of the difference wave (Successful Guessing minus Recognition) showed strong activity at the front-central region. Dipole analysis localized the generator of the N350 in the vicinity of the posterior cingulate cortex (PCC) and the inferior frontal gyrus. Secondly, a greater late positive component (LPC) in Successful Guessing than Recognition was found between 600 and 700 ms post-stimulus. Dipole analysis localized the generator of LPC in the right parahippocampal gyrus.  相似文献   

11.
We consider the Poisson integral u = P*μ on the half-space R+^N+1 ( N 〉 1 ) (or on the unit ball of the complex plane) of some singular measureμ. If μ is an s-measure (0 〈 s 〈 N), then some sharp estimates of the integration of the harmonic function u near the boundary are given. In particular, we show that fpr p〉1,∫R^Nu^p(x,y)dx- y^-τ (y〉0,τ =(N-s)(p-1) ) (Given for p〉1, RN f 〉 0 and g 〉 0, " f-g " will mean that there exist constants C1 and C2, such that C1f ≤ g ≤ CEf ).  相似文献   

12.
CLEFIA ( named after the French word "Clef" meaning "Key" ) is an efficient, highly secure block cipher proposed by SONY Corporation in the 14th International Workshop on Fast Software En- cryption ( FSE-2007 ) and many cryptanalyses have been used to analyze it. According to the proper- ty of CLEFIA, a new technique Sandwich-Boomerang cryptanalysis is used on it. An 8-round Sand- wich-Boomerang distinguisher of CLEFIA is constructed using the best differential characteristic of CLEFIA. And then, based on the distinguisher, an attack against 10-round CLEFIA is proposed. The number of chosen plaintexts required is 2^119(or 2^120) and the time complexity is 2^120(or 2^121). Compared with a 7-round impossible Boomerang distinguisher presented by Choy in the 4th Interna- tional Workshop on Security (IWSEC-2009) , the differential characteristics used in the attack are all the best ones, so it is believed that the attack is the best result that the Boomerang attacks can get on CLEFIA at present.  相似文献   

13.
Gelman and Bloom found that adults and children's object naming was sensitive to how an object was created (man-made or not), but they did not reveal on which specific level of conceptual system this effect was. Using a free-naming task and a force-choice task, two experiments were conducted to test a hypothesis that this effect was specifically on domain level ("artifact/non-artifact" distinction), in Experiment 1, participants were asked to name shortly-depicted objects, rate their confidence, and report their reasons for each naming response. Resuits showed that most of the naming responses in "man-made" condition were in artifact domain, and most in "natural" condition were in non-artifact domain, although in both conditions names were very divergent on basic level. In Experiment 2, another group of participants were asked to choose one from two names (one in artifact domain and the other in non-artifact domain) to match the same shortly-depicted objects presented in the first experiment. Results of Experiment 1 on domain level were replicated in Experiment 2. These convergent findings supported the hypothesis that the effect of object's origin is specifically on domain level of conceptual system of objects. Reasons explicitly reported for naming responses in Experiment 1 suggested that participants might automatically infer objects' functions in "man-made" condition but not in "natural" condition. Here the function-based hypothesis of artifacts classification is discussed.  相似文献   

14.
Polypeptide hybrid triblock copolymer, poly(L-glutamic acid)-b-poly(propylene oxide)-b-poly (L-glutamic acid) (PLGA-b-PPO-b-PLGA), was synthesized by the ring-opening polymerization of benzyI-L- glutamic N-carboxyanhydride (BLG-NCA) using poly(propylene glycol) bis(2-aminopropyl ether) as initiator, followed by the subsequent deprotection step. The obtained double hydrophilic triblock co- polymer exhibits "schizophrenic" micellization behavior in aqueous solution upon dually playing with solution pH and temperature. The multi-responsive micellization behavior of this polypeptide hybrid triblock copolymer has been thoroughly investigated by 1H NMR, laser light scattering (LLS), tempera- ture-dependent optical transmittance, and circular dichroism spectroscopy (CD).  相似文献   

15.
High precision elevation measurements using DGPS were carried out along three representative tran-sects for the "Great Ear" area, a dry salt lake within the Lop Nor basin. Results indicate that the Lop Nor basin is only 5.2 m deep and its lowest point occurs at the center of the "Great Ear". In addition, the basin is asymmetric-steeper in the southwest (0.19‰) and gentler in the northeast (0.09‰). Points along the same "Great Ear" ring were found to have an identical elevation value, but different when from different ones (lower towards the center). The spacing of the "Great Ear" rings was found to be closely related with the surface steepness. The closer the "Great Ear" rings are spaced, the steeper the ground surface, and vice versa. These findings support the argument that the "Great Ear" rings are the former shoreline trails left behind by Lop Nor water during the last few episodes of recession towards its total dry up. A comprehensive analysis of the high precision elevation data, historical accounts, aerial and satellite photographs and imagery, and official topographic maps of the study area suggests that the "Great Ear" area in the Lop Nor basin was incorrectly mapped as being covered by a great body of water on the 1963 topographic maps. A re-interpretation of the 1958 aerial photographs and newer remote sensing imagery indicated that the "Great Ear" ring structure was already in place in 1958 and it continued to appear on the subsequent remote sensing data without any major changes. It is estimated that lake water in the "Great Ear" area of the Lop Nor basin disappeared between the late 1930s and early 1940s.  相似文献   

16.
何静  潘慧 《广东科技》2011,20(13):27-30
一、科技传播与科技进步活动月 科技传播(Communication of Science and Technology),简称"科普",国外又称"公众理解科学(Public understanding of science)",是指科技知识和信息通过跨越时空的扩散而在不同个体间实现共享的过程,它包括专业交流、科技教育、科学普及和技术推广等基本步骤。它承担着把科技知识从其生产者、拥有者输送到社会以便供其他人学习和应用的任务。  相似文献   

17.
Refinement of reduced-models for dynamic systems   总被引:1,自引:0,他引:1  
A refinement procedure for the reduced models of structural dynamic systems is presented in this article. The refinement procedure is to "tune" the parameters of a reduced model, which could be obtained from any traditional model reduction scheme, into an improved reduced model. Upon the completion of the refinement, the improved reduced model matches the dynamic characteristics - the chosen structural frequencies and their mode shapes - of the full order model. Mathematically, the procedure to implement the model refinement technique is an application of the recently developed cross-model cross-mode (CMCM) method for model updating. A numerical example of reducing a 5-DOF (degree-of-freedom) classical mass-spring (or shear-building) model into a 3-DOF generalized mass-spring model is demonstrated in this article.  相似文献   

18.
With analysis of limitations Trusted Computing Group (TCG) has encountered, we argued that virtual machine monitor (VMM) is the appropriate architecture for implementing TCG specification. Putting together the VMM architecture, TCG hardware and application-oriented "thin" virtual machine (VM), Trusted VMM-based security architecture is present in this paper with the character of reduced and distributed trusted computing base (TCB). It provides isolation and integrity guarantees based on which general security requirements can be satisfied.  相似文献   

19.
Eichenbaum and colleagues observed that the same place did or did not activate the "goal-approach" cells in hippocampus depending on whether the place was the way for rats to approach specific goal. Parallel with this, the present neuroimage study revealed that, the same type of items could activate the hippocampus more when it was related to the task at hand than when it not. Participants were scanned by fMRI while they made judgments on the type of relationships contained in the word-pairs (e.g., Does the word pair, "furniture-table", contain a "category-exemplar" relationship?). Event-related analysis revealed that the forming of "task-related" association activated hippocampus more than that of "task-unrelated", even if it was the same type of items, and, this hippocampal difference was not caused by the different judgment requirements, nor by the effects of "yes" response. Consistently, the post-judgment cued-recall test exhibited a better retrieval performance for "task-related" associations than for the same type but "task-unrelated" associations. Results also showed that, the semantic relatedness between the to-be-associated individual words (e.g., the related word pair "healthy-hospital" versus the unrelated word pair "price-way") was not enough to activate the hippocampus when it was "task-unrelated". Generally, we proposed that, through participating in forming of "task-related" associations and consolidating of episodic memory, hippocampus enabled the organism to keep the information that owned great survival values in mind for future usage.  相似文献   

20.
本书是德国Springer丛书《光学科学》的第142卷。丛书的主编是美国佐治亚技术学院(Georgia Institute of Technology)的W.T.Rhodes教授。本书是著者罗斯教授在德国达姆施塔特技术大学(Technische Universitot Darmstadt)多年教学的基础上写成的,也融入了他近年在劳伦斯-伯克利国家实验室(Lawrence Berkeley National Laboratory)讲授带电粒子光学课的内容。像差、曲轴系统以及像差校正方面的大部分内容来自著者本人几十年来的研究结果。  相似文献   

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