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1.
非马克思主义者由于不能以实践的观点和辩证的观点理解城市而无法发展出一种总体性的城市理论。马克思和恩格斯虽然提供了以历史唯物主义分析城市问题和都市形式的线索,但也引发了“城市中的社会”研究还是“城市社会”研究的争论。随着人类城市化进程的不断深化,理论和实践两方面的诉求使澄清作为一种城市研究范式的“都市马克思主义”成为当前之需。马克思主义探究的社会现实是人类生产自己生活方式的具体的总体,而城市是人类生产自己生活的一定方式,因此研究城市必须将其放置于人类生产活动构成的社会总体之中。当今时代,都市已成为人类生产自己生活的自觉方式和社会历史发展的主导性构成。作为城市研究的马克思主义范式和马克思主义的当代哲学范式,都市马克思主义以包含着丰富矛盾性的“都市”为理论总问题,以实践的观点辩证地理解和揭示现代世界的都市现实,是一种微观视域和宏观视域相结合,真正探究现实的人的生存状况、生存矛盾、生活方式和生活意义的社会历史理论。具体来说,它致力于建构都市的社会历史解释模式,展开都市政治经济学批判和都市文化批判,提供与人类解放实践相连的都市革命理论。 相似文献
2.
Iyota H Tomimitsu T Shimada K Ikeda N Motomura K Aratono M 《Journal of colloid and interface science》2006,299(1):428-434
Adsorption and micelle formation of a surfactant in the presence of inorganic salts with different charge numbers of cations were investigated from the viewpoint of mixed adsorption and micelle formation of salt and surfactant. Surface tension of aqueous solutions of the mixtures of octyl methyl sulfoxide (OMS) with calcium chloride and lanthanum chloride was measured as a function of the total molality of the mixture and the mole fraction of OMS in the mixture at 298.15 K under atmospheric pressure. Composition of the adsorbed film and micelle was numerically evaluated from the dependence of the total molality at a given surface tension and the mixture CMC on the bulk composition to draw phase diagrams of adsorption and micelle formation. Judging from the phase diagrams together with the ones of the sodium chloride system, miscibility of inorganic salt and OMS in the adsorbed film and micelle increases with an increase in the charge number of inorganic cation, which is attributable to the attractive interaction between inorganic cation and the polar head group of OMS molecule in the adsorbed film and micelle. 相似文献
3.
Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given. 相似文献
4.
Tikhonova I. G. Baskin I. I. Palyulin V. A. Zefirov N. S. 《Russian Chemical Bulletin》2004,53(6):1335-1344
A system of virtual screening of organic molecule databases is designed, which permits preprocessing of databases, molecular docking to a three-dimensional model of receptor, and post-processing of the results obtained. Using this screening system, it is possible to reproduce positions of the known ligands in the glutamate sites of the NMDA and AMPA receptors and in the glycine site of the NMDA receptor, to substantially enrich the database with potentially active compounds, and to distinguish between the agonistic and antagonistic character of the action of these compounds in the case of docking to the open and closed forms of the binding sites. Based on the results of screening of a database of low-molecular-weight organic compounds (total of 135,000 structures) using models of the open and closed forms of the glutamate and glycine sites of the NMDA receptor and of the glutamate site of the AMPA receptor, focused libraries of potential agonists and antagonists of these sites were designed. 相似文献
5.
G González-Neves D Charamelo L Barreiro G Gatto A Tessore M Moutounet 《Analytica chimica acta》2004,513(1):191-196
The phenolic potential of Tannat, Cabernet-Sauvignon and Merlot grapes was evaluated in 2001 and 2002 and its correspondence with the colour and composition of the respective wines was established. Three vineyards of each variety, situated in the south of Uruguay were considered. Two samples of each vineyard were taken at the moment of the harvest. Phenolic richness, extractable anthocyanins contents and total potential in anthocyanins of the grapes were estimated. Two fermentations on skins were carried out for each vineyard using 50 kg of grape in each one. The anthocyanic and total polyphenols contents of the musts were analysed every 24 h, and skins extractions were carried out in parallel in the laboratory. The duration of the maceration for each variety was decided in function of the analytical results in the grapes, musts and skins extractions. Wines were analysed 2 months after the alcoholic fermentation, determining its phenolic composition and colour. Tannat grapes presented anthocyanic and total polyphenols contents significantly higher in both years. Therefore, wines from this variety presented colour intensity and phenolic contents statistically higher than Cabernet-Sauvignon and Merlot. The correlations between the phenolic contents of the grapes, skins, musts and wines were very significant. Colour intensity and phenolic contents of the wines were highly correlated with the total polyphenols of the grapes and with anthocyanins of the grapes, skins, musts and wines. The estimate of the phenolic potential of the grapes and the extractability of the pigments allows to manage more adequately the fermentation on skins and is an interesting tool to predict the colour and the composition of the wines. 相似文献
6.
Measurement of protein-DNA interaction parameters by electrophoresis mobility shift assay 总被引:22,自引:0,他引:22
M G Fried 《Electrophoresis》1989,10(5-6):366-376
Native gel electrophoresis (mobility shift) assays may be used to obtain quantitative information about the site distribution, equilibria and kinetics of protein-DNA interactions. These applications depend on the ability of the electrophoretic system to resolve the reaction components, and on their stabilities during the separation process. Factors which affect the lifetimes and mobilities of protein-DNA complexes during electrophoresis include reaction and electrophoresis buffer composition, pH, and ionic strength; the presence of low molecular weight effectors and enzymatic substrates; the nature and concentration of the gel matrix; the temperature; the molecular weights of protein and DNA; the stoichiometric ratios of their complexes; and the possibility of conformational and configurational isomerization of reaction components. We discuss how these factors influence the acquisition of quantitative data from electrophoretic patterns and band intensities, and present formulas for the estimation of equilibrium constants and rate constants for prototypical DNA-protein interactions. 相似文献
7.
基于马克思主义政治经济学的学理依循,尝试沿着经济制度−社会核心经济制度、基本经济制度与具体经济制度(包括微观、中观、宏观)这一内在向度的致思路径,并嵌入生产力—生产关系(经济基础)—上层建筑整体系统的外在向度来诠释经济制度的适应性调整和互动性促进。“双向度变迁”的理论分析,旨在把握中国社会主义经济制度变迁的内生性与阶段转换的自洽性,以洞悉新中国经济制度变迁更为深层的结构性变化和纵跃历史的变迁线索及其规律性大势的方向。进一步客观理性地理解新中国经济制度70年的变迁路径、特征、绩效,及其重大的理论与实践创新意义。 相似文献
8.
为探讨氧自由基和锌、铜在视网膜脱离后增殖性玻璃体视网膜病变 (PVR)中的作用 ,收集了 48例视网膜脱离患者视网膜下液 (SRF) ,利用紫外分光光度计测定了SRF中LPO的含量和SOD的活性 ,用原子吸收光谱法测定了Zn、Cu的含量。结果表明 ,随着PVR程度及玻璃体浑浊的加重、病程的延长 ,LPO含量增加 ,SOD活性明显下降 ,P <0 0 5 ,差异有统计学意义。提示SRF中LPO、Zn、Cu含量及SOD活性的改变与视网膜脱离后PVR的发生、发展有密切关系。 相似文献
9.
N M Zaslavsky BYuMestechkina L M Miheeva S V Rogozhin 《Journal of chromatography. A》1983,256(1):49-59
The partition behaviour of human serum albumin and oxyhaemoglobin and several amino acids and small peptides was studied in the aqueous Ficoll-dextran biphasic system as a function of the ionic composition and pH. The partition coefficients of the solutes were expressed in terms of the equivalent number of CH2 groups, nCH2, and the equivalent number of carboxyl groups, m. The physical meaning of these two parameters and of the relationships found between them and pH for the proteins examined are discussed. A correlation was established between the difference in the relative hydrophobicities of the individual phases of various water-organic solvent systems and the interfacial tension, gamma 12, of the systems. It is argued that a relation of a similar type exists for the aqueous polymeric biphasic systems. The possibility of estimating the relative intensity of Van der Waals and hydration interactions of a solute and particle surface by examination of their partitioning in a biphasic system calibrated for the hydrophobic and hydration properties of the phases is discussed. 相似文献
10.
无论是基于伯林的概念框架,还是超出伯林的概念框架,对第三种自由概念的可能性及其成立依据的探究已经成为当代政治哲学的一个重要生长点。就自由平等主义而言,我们可以把关于消极自由的定义以及自由的价值问题的争辩,从理论上落实为罗尔斯的基本自由权理论对于自由问题上内外两种路径的整合;就公民共和主义而言,价值多元论仍然是提出第三种自由概念时必须正视的挑战和重建其自由理论的平台,而自由的原子层次和分子层次的区分又为调和自由平等主义和公民共和主义提供了一种有效的概念手段;就哈贝马斯与罗尔斯之争而言,围绕私人自主和公共自主以及所谓更高阶的政治自主性所展开的争论和回应,所指向的乃是政治哲学对于透明性理想的追求。 相似文献
11.
古地图不仅是古代地理状况的反映,也是政治权力和地理观念的表达。汉代张骞凿空西域以来,中原王朝对西域的政治关怀、中原士人对西域的历史书写和知识关注从未中断。汉唐时期的西域地理图籍因年代久远、写本时代文献传存不易而未能流传至今。宋元明时期,中原王朝和西域民族政权都有西域图籍传世,分别表现了不同的西域景观和西域观念。并未实际掌控西域的宋、明王朝在其疆域图中往往表现汉唐时期的西域历史镜像,突出中原王朝经营西域的文治武功,彰显西域是中原王朝故土的政治观念,寄托中原王朝徕远人、致殊俗的政治理想。元代西域地图受中国地图和阿拉伯地图的双重影响,表现西域突厥化、蒙古化的地理现实。明代西域行程图重在表现明代广义西域的交通、城镇、物产与族群地理现状,反映元明时期西域突厥化和伊斯兰化的现实情景。宋明学者的知识关怀和元明王朝的政治经略是该时期西域地理图籍传承和发展的主要动力,而西域也在不同朝代、不同类型、不同知识体系的地图中呈现出历史与现实、故土与异域相互交错的地理景观。 相似文献
12.
溯源法是道德发生学的主要方法。用溯源法考察古希腊罗马感性善恶观的源流,可以发现,荷马时代的希腊人已经生成一种以善恶观念为基本工具的道德判断模式,有了自己的感性善恶观。诗人荷马和赫西俄德将这两种道德观念具体化,对众多行为提出道德判断和评价,进而提出道德训诫,从而使他们的作品发挥道德教化的作用。希腊早期和古典时期哲学家的善恶观表明,理性思维的诞生为希腊伦理思想的发展提供了助力。历代哲学家不断地对荷马、赫西俄德式的感性善恶观进行理性加工,在此基础上发展出理论形态各异的理性善恶观。理性善恶观在希腊化时期和罗马帝国时期继续扩展和传承,形成内容和结构各异的理性善恶观。 相似文献
13.
E. A. Miroshnichenko T. S. Kon’kova Ya. O. Inozemtsev Yu. N. Matyushin 《Russian Chemical Bulletin》2010,59(5):890-895
Based on the experimental results and the published data, the enthalpies of formation of ethane and propane nitro derivatives
were obtained for both the standard state and gas phase. The bond dissociation energies of the ethane and propane nitro derivatives
were calculated using the enthalpies of atomization and the energies of nonvalent interactions of nitro groups. The calculated
values were compared with the kinetic data on thermal decomposition. The bond dissociation energies in radicals of the ethane
and propane nitro derivatives were also calculated using the enthalpies of atomization and the energies of nonvalent interactions
of nitro groups. Regularities of changes in the bond dissociation energies of the ethane and propane nitro derivatives and
their radicals were established. 相似文献
14.
纳米材料由于其独特的光、电、磁、力学等性质,成为了构建功能材料与器件的理想基元。实现纳米粒子的精确组装,是探究粒子之间的耦合聚集性质和制备宏观功能器件的基础。但是由于纳米粒子的小尺寸以及在溶液中运动的随机性与复杂性,精准控制纳米粒子组装体的形貌以及在空间中的相对位置仍存在巨大挑战。为了将纳米粒子组装成理想的有序结构,许多控制粒子组装的策略与方法得到发展。本文首先概述了纳米粒子自组装的控制方法与典型形貌,着重分析了影响粒子精准排布的因素与控制方法,并对纳米粒子及其组装体的光学性质与器件应用的最新研究进展进行了讨论,最后对目前纳米粒子精准组装所面临的挑战以及未来发展的方向进行了展望。 相似文献
15.
The structural features of complexes of 1-hydroxyethylidenediphosphonic acid (HEDP) with different metals (geometric isomerism, dentate numbers and the mode of coordination of organophosphorus ligand, the structural type and degree of oligomerization, regular distortions of the coordination polyhedron, and the mutual influence of the ligands) are considered. The dependences of the complex structures and of the degree of deprotonation of the HEDP ligands on the synthesis conditions (solution pH and metal : HEDP ratio), on the nature of the metal and the outer-sphere cation, on the composition of the hydrate sphere, and on the availability of the accompanying ligands are also established. 相似文献
16.
The wettability of polytetrafluoroethylene and polymethyl methacrylate by aqueous solution of two cationic surfactants mixture 总被引:1,自引:0,他引:1
Szymczyk K Zdziennicka A Jańczuk B Wójcik W 《Journal of colloid and interface science》2006,293(1):172-180
Advancing contact angle (theta) measurements were carried out for aqueous solutions of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium bromide (CPyB) mixtures on polytetrafluoroethylene (PTFE) and polymethyl methacrylate (PMMA). The obtained results indicate that the wettability of PTFE and PMMA by aqueous solutions of CTAB and CPyB mixtures depends on the composition and concentration of the mixture; however, synergism in the wettability does not exist. In the range of low concentrations of aqueous solution mixtures there is a linear dependence between the contact angle and composition of the mixtures, but at a concentration close to CMC a deviation from linear dependence is observed. In contrast to Zisman, there is no linear dependence between costheta and the surface tension of aqueous solution of CTAB and CPyB mixtures, but a linear dependence exists between the adhesional and surface tension, and these lines have a slope -1 and -0.34 for PTFE and PMMA, respectively, which suggests that adsorption of CTAB and CPyB mixtures at water-air and PTFE-water is the same, and the orientation of the CTAB and CPyB molecules at both interfaces in the saturated monolayer should also be the same. Adsorption of these mixtures at water-air interface is considerably higher than at PMMA-water interface, and CTAB and CPyB molecules should be parallelly oriented to PMMA surface in the saturated monolayer. Extrapolation of the straight lines to the points corresponding to the surface tension of aqueous solution, which completely spreads over the PTFE and PMMA surface, gives a critical surface tension of wetting equal to 23.44 and 33.13 mN/m, respectively. The value of 23.44 mN/m is higher than that of the surface tension of PTFE, but the value of 33.13 is lower than that of Lifshitz-van der Waals components of PMMA surface tension. On the basis of the critical surface tension, the surface tension of PTFE and PMMA, the Young equation, and thermodynamic analysis of the adhesion work of aqueous solution of surfactant to polymer surface, it was found that for PTFE and PMMA the changes of the contact angle of aqueous solution of two cationic surfactants mixtures on their surfaces as a function of the solution concentration resulted only from the decrease of the polar component of the solution surface tension. 相似文献
17.
研究了对羟基苯甲酸溶剂浮选的浮选条件优化和回收动力学规律。考察了溶液的pH、通气速度、溶液离子强度、浮选时间、相比以及浮选溶剂等因素对对羟基苯甲酸浮选效率的影响,优选了浮选条件。研究表明对羟基苯甲酸的溶剂浮选过程符合一级动力学方程,表观速率常数随空气流速的增加而增大。 相似文献
18.
中药指纹图谱学体系在中药创制中的作用 总被引:3,自引:0,他引:3
从整体论、系统论和复杂科学的角度论述了中药指纹图谱学体系的构成背景和核心任务。中药指纹图谱学体系具有体系科学性质,是从系统性和整体性角度研究中药(包括植物药)的物质基础和作用机制以及药代动力学规律和相关制剂技术的崭新学科。该体系以中药指纹图谱信息学为核心和桥梁,包括中药指纹图谱测试学、中药指纹图谱质控学、中药指纹图谱谱效学、中药指纹药物动力学、中药指纹药剂学和中药生物指纹图谱学。该体系的研究需采用复杂科学和体系科学的理论和方法,突破线性思维和还原分析,强调宏观和系统的有机综合,应用数学科学原理和方法来开辟中药创制的新模式。中药指纹图谱学的理论体系和方法是解析中药的主导技术和实现中药现代化的核心力量,该体系理论和技术的成熟及完善可为现代中药创制提供强有力的理论和技术支撑。中药指纹图谱学体系的最终目的是为人类和有益生物研制出疗效显著、安全、可控的现代化中药。 相似文献
19.
中国文化一直以“天人合一”为至上追求。但在不同的时代,天人合一又有其不同的内涵,比如在理学的开创阶段,天人合一就表现为本然与实然的统一,这种统一正好表现在张载以“虚气相即”为代表的本体论与宇宙论的并建与统一上,理学的本体宇宙论即由此得以确立。到了朱子时代,天人合一又表现为理与气的不即不离;但理和气本然与实然的两属以及“所以然”与“所当然”的不同侧重,又意味着“尊德性”与“道问学”、理本论与气化宇宙论的分裂。到了王阳明,才从官场与学界共同的内外背反现象中发现了知行为二的根源,所以其从身心一致的“知行合一”出发,并通过致良知,从而完成了从知行到身心、主客包括本然与实然两重世界的统一;而从批评程朱未能“定于一”的罗钦顺起始,则又从理与气之不可分割特征入手走向了气学。这样一来,心学与气学,既是中国文化天人合一追求的两种不同走向,同时也代表着中华民族现代化追求的双重资源。 相似文献
20.
The effects of various subclasses of flavonoids, Rose Bengal, and different styrylpyridinium dyes on the magnitude of the dipole potential of membranes composed of pure phospholipids and sterol-containing bilayers were investigated. Changes in the steady-state membrane conductance induced by cation-ionophore complexes were measured to examine the changes in the dipole potential of lipid bilayers. The characteristic parameters of the Langmuir adsorption isotherm for different flavonoids and Rose Bengal and the slope of the linear dependence of the dipole potential change on the aqueous concentrations of RH dyes were estimated. Chalcones (phloretin and phloridzin) and flavonols (quercetin and myricetin) strictly decrease the dipole potential of phospholipid- and sterol-containing membranes; the unsaturation of the C-ring and the hydrophobicity of the molecule contribute to the ability of the flavonoid to reduce the bilayer dipole potential. Rose Bengal decreases the magnitude of the bilayer dipole potential to a similar extent, but its affinity for membrane lipids is higher; the effects of RH dyes, chalcones, and phloroglucinol are determined by sterol concentration and type. 相似文献