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The concept of tianxia (All-under-Heaven) has been described as a Chinese version of cosmopolitanism. However, tianxia is a hard-to-define term, with political, cultural, and geographic meanings. From the fifteenth century onwards, maps exist that claim to show tianxia, therefore allowing us to reconstruct how Chinese mapmakers understood tianxia’s geographic extent. Other terms in the titles of maps that show space beyond the borders of the Ming and Qing states include huayi (civilized and barbarian/Chinese and non-Chinese), wanguo (10,000 countries), and sihai (four seas). This article examines the geographic extent of these terms and changes in their usage between the fifteenth and eighteenth centuries. It argues that Ming Chinese mapmakers and scholars presented tianxia as equivalent to the Ming empire and used terms such as huayi and wanguo to advertise the maps as showing regions far away, like western Asia and the Americas. Jesuits in China, on the other hand, applied a broader meaning of tianxia, equating it with the whole globe. During the Qing, the extent of tianxia expanded to represent a cosmopolitan empire connected to a range of surrounding states, embedded in a wider world.
Tosudite was found in the Hokuno pottery stone mine, Gifu Prefecture, Japan. The pottery stone ore body, altered from the Cretaceous rhyolitic rock, is composed of tosudite, interstratified illite-montmorillonite, kaolinite and quartz. Prepared by normal sedimentation method, the specimen is composed of 75.6% tosudite, 24.0% kaolinite and 0.4% quartz. The chemical composition of the specimen is SiO2 45.09%, TiO2 tr., Al2O3 37.31%, Fe2O3 0.94%, MgO 0.41%, CaO 1.94%, Li2O 0.45%, Na2O 0.09%, K2O 0.44%, H2O(−) 1.50% and ignition loss 12.11%. After subtracting the compositions of the impurities, the structural formula of tosudite is given as; interlayer cations K0.23, Na0.07, Ca0.86 + nH2O; ‘gibbsite’ layer Li0.76, Mg0.35, ${\rm{Fe}}_{0.29}^{3 + }$, Al3.34 (OH)12.00; silicate layer Al8.00 [Si13.83 Al2.17] O40.00 (OH)8.00.
Syntheses of tosudite were made from a starting material which is an interstratified illite-montmorillonite obtained from the same ore body. At 450°C, 400atm., reacting for 5 days, a tosudite-like mineral was synthesized.
Chelating organic acids hampered the hydrolytic reactions of Al and affected the nature of the crystalline aluminum hydroxides. Chemical composition, structure, size, nature of functional groups, and concentration of each organic anion, as well as the pH of the system, controlled the rate of Al(OH)3 crystallization. The order of effectiveness of the various acids was: glutaric < succinic = phthalic < glycine < malonic < glutamic < aspartic < oxalic < salicylic = malic < citric < tartaric. An increase in the stability of complexes formed between the organic ligands and Al decreased the rate of crystallization and changed the final aluminous products from bayerite to nordstrandite and/or gibbsite and then to pseudoboehmite and/or amorphous material. In the presence of anions with a great affinity for Al, particularly at pH equal to or less than 9.0, the reaction products were commonly poorly crystalline or structurally distorted. In the range of pH 8.0 to 10.0 moderately or strongly chelating anions acted to retard or prevent olation and facilitated the formation of stable pseudoboehmite or X-ray-amorphous products. The stronger the chelating power or the higher the concentration of organic anions, the easier was the formation of pseudoboehmite or amorphous material.
Electron spin resonance (ESR) spectroscopy is used to investigate the nature of exchange sites on kaolinite. ESR spectra of exchangeable Cu2+ and Mn2+ on kaolinite indicate that divalent exchange ions are about 11–12Å apart on kaolinite surfaces and that planar Cu (H2O)42+ ions are oriented parallel to the surfaces. Solution-like spectra for exchangeable Cu2+ and Mn2+ are observed at high relative humidities, suggesting a high degree of mobility of exchange cations on kaolinite surfaces. The evidence seems to eliminate edge sites as being active in cation exchange at least in the acidic range of pH. Similar conclusions are derived from ESR studies of Cu2+-saturated talc and pyrophyllite. It is proposed that most exchange sites arise from ionic substitutions or mineral impurities in phyllosilicates.
This paper analyzes the 2003 Iraq War's origins through the lens of orientalism and within the history of liberal empire. It argues that Edward Said correctly contended that an orientalist emphasis on essential difference helped justify the war. However, Said overlooked how liberal assertions of universal values also served as a basis for empire in this case and how many opponents of the war also drew on orientalist ideas. Simultaneously, opponents of the Iraq War often used orientalist binaries and stereotypes in their arguments for restraint. It concludes that in using cultural lenses in policy analysis, scholars should pay close attention to shifting contexts and appreciate the multidirectional potentialities of cultural factors for policy.
The hydroxyl orientations in the 2H2 polytype of amesite, Mg2Al(SiAl)O5(OH)4, have been determined by minimizing the electrostatic potential energy as a function of OH orientation. The angles, ρ, between the hydroxyls and (001) vary between 81.5 and 88.8°. All surface hydroxyls form hydrogen bonds with oxygens of the adjacent layer. The OHs tend to tilt away from the higher charged A1VI ions, and the spread in ρ values is due to variations in the positions of the receptor oxygens. The inner hydroxyls noticeably weaken the interlayer bonding. The substitution of Al in both T and M sites creates a dipolar layer charge and the resulting attraction between layers forms an important part of the interlayer bonding. The 2H2 polytype of amesite has substantial interlayer bonding even with all surface hydroxyls replaced by fluorine. This is not true for a composition of Mg3Si2O5(OH)4 where a similar F for OH substitution destroys all interlayer bonding as in kaolinite.
Aerogels of clays can be prepared by freeze-drying of clay water gels. The mechanical strength of the aerogels is improved by the addition of water-soluble polyelectrolytes to the hydrogels.
The porosity of the powdered aerogels can be adapted to the requirements for adsorbents in gas chromatography by compounding the hydrogels with suitable amounts of polyelectrolytes. Simultaneously, the surface of the clay may be modified by adsorption of polar or cationic organic compounds in order to achieve specific chromatographic separations.
Because of the toughness of the clay-polyelectrolyte aerogels, they can be rolled out to thin sheets which may be applied as chromatographic papers.
The characterisation, legal status and future of islands are increasingly prominent in international and legal affairs. This emerging ‘legal era of islands’ demands a clearer understanding of the multiple distinctive legal issues that islands, whether as sub-national political units or as the territory of continental or mainland States, raise. This article conducts the first contemporary study of these issues by examining the international and constitutional legal status of island territories. It finds that although the relationship between islands and mainland States is characterised by incredible diversity, island territories are pursuing a range of innovative strategies to preserve and protect their autonomy.
Some authors have stated that anionic surfactants are not adsorbed by montmorillonite while others indicate very minor adsorption. Attempts to quantitatively determine the degree of adsorption have shown that certain problems exist which, unless recognized, will completely mask results. Some of these difficulties have been overcome but exact data have not yet been obtained. However, enough information has been gathered to prove that adsorption of anionic surfactants on montmorillonite is real and substantial. Reliable adsorption data for cationic and nonionic surfactants and one having both nonionic and anionic character have been obtained. It is indicated that 550 mg of these surfactants are adsorbed by 1 g of montmorillonite. X-ray diffraction data for complexes of all surfactants investigated confirm positive adsorption. However, the thickness of the adsorbed surfactant layers cannot always be quantitatively related to the amount of adsorbed surfactant.
The relationships between spectrum and structure in layer-silicates are reviewed, and applied in the study of structural changes occurring during the heating of montmorillonites up to dehydroxylation, and their subsequent rehydroxylation. Information given by infrared spectroscopy on the binding of water in expanding layer silicates is presented, and the physical and chemical processes associated with entry of basic, neutral and acidic molecules into the interlayer space of these minerals are illustrated for ammonia, ethylamine, pyridine, nitrobenzene, and benzoic acid. Problems associated with the study of soil clays, which are often complex mixtures including poorly ordered and amorphous constituents, frequently firmly combined with organic matter, are discussed.
New evidence is presented concerning the environment of the two types of hydroxyl group in beidellite. The thermal stabilities of NH4+ and lattice OH in montmorillonite and beidellite, and the properties of their dehydroxylates, are contrasted. The nature of the collapsed phase formed in Li-, Mg-, and NH4-montmorillonite at 300–500°C is discussed. The presence of weak hydrogen bonds between lattice oxygens and interlayer water is established, although it is shown that the strength of hydrogen bonds formed between NH4+ and lattice oxygens is dependent on the sites of substitution in the layer lattice.
Serpentine- and talc-like garnierites described in Parts I and II were heated at various temperatures up to about 1000°C and after each treatment were cooled and examined by X-ray powder diffraction. The serpentine-like garnierites at about 550°C, the temperature at which rapid dehydroxy-lation begins, formed a highly disordered phase. When the NiO content was low (approximately < 20 wt%), the disordered phase transformed directly to an olivine phase around 800°C, but when the NiO content was higher, various transitional phases were formed before an olivine phase appeared around 1000°C. A sepiolite-like phase was obtained with one sample around 800°C, and several samples showed face-centered cubic modifications between 900 and 1000°C.
The talc-like garnierites with low NiO content formed an enstatite phase around 800°C directly following the dehydroxylation reaction, but with high NiO contents an olivine phase became increasingly prominent between 850 and 1000°C. Identification of the mixed crystallizations possibly existing in the initial minerals is scarcely feasible on the basis of the products formed up to 1000°C.