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101.
Three North Dakota lignites with almost the same percentage carbon have been used to determine the relation between chemical structure and reactivity to hydrogenation. Average structural indices of the lignites were estimated using the pyridine-soluble products after alcohol-alkali treatment, the structural indices obtained at various reaction times being extrapolated to zero reaction time. Hydrogenation was influenced by the average structure, with the lignite having higher aromaticity, higher molecular weight of the pyridine extract from the alcohol-alkali reaction product, larger aromatic ring size and lower content of aliphatic structure, showing a smaller degree of conversion. 相似文献
102.
103.
Aleksei B. Burdukov Mikhail A. Vershinin Ilya V. Eltsov Nataliya V. Pervukhina Yan Z. Voloshin 《Inorganic chemistry communications》2009,12(9):919-922
The controlled hydrolysis of the dichlorine-containing iron(II) clathrochelate FeBd2(Cl2Gm)(BF)2 precursor (where Bd2− and Cl2Gm2− are α-benzyldioxime and dichloroglyoxime dianions, respectively) afforded the hydroxy-containing clathrochelate derivatives with the hydroxyl substituent inherently bound to the ribbed chelate fragment of the macrobicyclic ligand. The triethylammonium and tetra-n-butylammonium salts of the clathrochelate [FeBd2(OClGm)(BF)2]− anion have been characterized using elemental analysis, MALDI-TOF mass spectrometry, IR, UV–Vis, 57Fe Mössbauer and 1H, 13C{1H}, 11B and 19F NMR spectroscopies, and X-ray crystallography. The X-ray structural data for this deprotonated anion showed strong delocalization of its negative charge into the clathrochelate framework. 相似文献
104.
韩志成 《南水北调与水利科技(中英文)》2008,6(1):322-323,333
唐河倒虹吸工程是南水北调中线总干渠工程中的大型建筑物之一,主体混凝土截至目前已基本完成,所验收单元工程质量优良率为92%,混凝土内实外光,施工缝连接平顺,无裂缝.现就混凝土施工中的原材料选定、配合比、温度控制、管身混凝土关键部位的施工措施等内容进行了浅释. 相似文献
105.
Stress corrosion cracking (SCC) raises a lot of questions concerning complexity of stacked physical mechanisms. Synergy between electrochemical processes and mechanical field near the crack tip is now recognized. However, the influence of mechanical behaviour on corrosion processes is not well established and only few works dealt with this effect. Consequently, it seems to be necessary to determine the influence of the plastic strain on the surfaces reactivity in aqueous mediums. The great part of this work was devoted to the development of an electrochemical cell on a bench of mechanical test in order to carry out in situ measurements of current density. Three levels of interaction have been discussed taking into account the different expression of plastic deformation (dislocation density and distribution, slip bands emergence, stress field) in order to study the effect of mechanical state on dissolution, on passivation processes, and on stability of oxide film of polycrystalline nickel in H2SO4 solution. 相似文献
106.
M. Mori Y. Kagami S. Kanemoto T. Tamaoki M. Enomoto S. Kawamura 《Progress in Nuclear Energy》2005,46(3-4):241-252
A new method for estimating reactivity parameters, such as moderator temperature coefficient (MTC) and void reactivity coefficient (VRC), is proposed using steady-state noise data. In order to solve the ill-posed problem of reactivity parameter estimation, a concept of a gray box model is newly introduced. The gray box model includes a first principle based model and a black-box fitting model. The former model acts as a priori knowledge based constraints in a parameter estimation problem. After establishing the gray box and noise source models, the maximum likelihood estimation method based on Kalman filter is applied. Furthermore, it is shown that the frequency domain approach of the gray box model is useful in the case of VRC estimation. The effectiveness of the proposed algorithms is shown through numerical simulation and actual plant data analysis. 相似文献
107.
The authors evaluated whether completing a multi-item assessment of smoking craving (the Questionnaire of Smoking Urges [QSU]) promoted increases in smoking craving. A sample of 39 regular smokers was randomly assigned to 1 of 3 manipulations (each of 3 min duration): (a) complete the QSU–Brief (10 items), (b) complete a noncraving questionnaire that was structurally identical to the QSU–Brief (scale-based control), and (c) a time-based control. Participants responded to an oral question assessing their degree of craving immediately before and after the manipulations. Results indicated that the QSU did not promote increases in craving compared to the 2 control conditions. Despite continuing debate over the most appropriate self-report measure of craving, investigators who use the QSU–Brief can be reasonably sure that the scores that result are not biased due to reactivity effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
This study examined the modulatory function of Duchenne and non-Duchenne smiles on subjective and autonomic components of emotion. Participants were asked to hold a pencil in their mouth to either facilitate or inhibit smiles and were not instructed to contract specific muscles. Five conditions--namely lips pressing, low-level non-Duchenne smiling, high-level non-Duchenne smiling, Ducherme smiling, and control--were produced while participants watched videoclips that were evocative of positive or negative affect. Participants who displayed Duchenne smiles reported more positive experience when pleasant scenes and humorous cartoons were presented. Furthermore, they tended to exhibit different patterns of autonomic arousal when viewing positive scenes. These results support the facial feedback hypothesis and suggest that facial feedback has more powerful effects when facial configurations represent valid analogs of basic emotional expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Thermal treatments, such as combustion, gasification, and pyrolysis, have been proven to be a convenient alternative to conventional sludge disposal technologies. Today, process development implies scaling up and so improving the reactor's design. In continuously operated reactors, fresh sewage sludge is in contact with solid residues (reacted material rich in mineral matter and char). Mineral matter has been reported to catalyze the thermo-chemical reactions involved but few works focus on this aspect. In this work, sewage sludge residues were added to fresh sewage sludge. Non-isothermal thermo-gravimetric analysis (TGA) coupled with infrared spectrometry (FTIR) showed that added residues reduce the characteristic reaction temperatures during char combustion and gasification (air, air-N2, and CO2 atmospheres). However, any considerable influence of residues was observed during pyrolysis experiments (N2 atmosphere). The analysis of gas produced during those experiments revealed further details about the solid decomposition, showing considerable differences between different atmospheres. 相似文献
110.
选用合适单体合成高反应活性聚酯树脂,介绍了树脂的合成工艺,以高亚氨基部分醚化氨基树脂为交联剂,自制二壬基二磺酸为催化剂,制成低温固化卷材涂料。所制备的涂料具有很好的耐候性和加工成型性能。讨论了影响涂料性能的因素。 相似文献