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The Japanese empire’s occupation of China during the Second World War left a complex and bitter legacy in postwar Chinese society. This article examines the occupation and its legacies at the grassroots, taking university students in Nanjing as a case study in occupation history and ‘bottom-up’ wartime commemoration. These young people, who studied at National Central University (NCU) under the Japanese-backed Reorganized National Government of Wang Jingwei, organized three protest movements between 1940 and 1945, defying puppet authorities, Japanese forces, and, after the war, the returning Chongqing Nationalist government, as they campaigned against corruption, opium sales, and discriminatory treatment over their status as ‘bogus students’ who supposedly received Japanese ‘enslavement education’ from a collaborationist regime. In the 1980s, after decades of marginalization under the People’s Republic of China, these former protestors began holding reunions, documenting their experiences, and campaigning for recognition from Nanjing University, which eventually recognized them as alumni. Drawing primarily on privately printed alumni memoirs and commemorative volumes, this article positions the protests in the history of youth activism in Nanjing. That NCU students were able to rehabilitate themselves was due to their own organizational prowess and a sympathetic reception from the leadership of a cash-strapped Nanjing University, though the interests of fellow alumnus Jiang Zemin and the Communist Party-state still set the parameters of historical memory. In this, the example of the Nanjing students complicates the top-down role of the state, as described in much previous scholarship on Chinese wartime commemoration, in producing politically motivated nationalist narratives of wartime history.
Due to swelling, smectite minerals are capable of intercalating many organic molecules in their interlayer space. Tetracycline (TC) is a group of antibiotics used extensively in human and veterinary medicine. The great aqueous solubility and long environmental half life of TC mean that the study of interactions between swelling clay minerals and TC are of great importance in TC transport and retention in subsurface soils. In the present study, the intercalation of TC molecules at different levels into smectites was investigated using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The shift of the FTIR bands of amide I and II in comparison to crystalline TC suggested a strong interaction between the amide groups and the clay surfaces. The band at 1455 cm−1 remained the same after TC intercalation into SAz-1, SWy-2, and SYn-1, suggesting that complexation was not a dominant mechanism of TC uptake by these minerals. With cation exchange as the major mechanism of TC intercalation into these minerals, simultaneous removal of H+ from solution protonated the TC molecules and provided a positive charge to interact with negatively charged mineral surfaces even in neutral to slightly alkaline conditions. The increase in interlayer distance after intercalation by TC, as revealed by XRD, suggested a tilted orientation of the intercalated TC molecules in both twisted conformation in acidic condition and extended conformation in alkaline condition.
The development of nanoparticles incorporating Gd3+ has attracted interest in the field of contrasting nanomedicine for magnetic resonance (MR) and computed tomography (CT). In order to achieve an effective contrasting performance, the amount and stability of Gd incorporated as well as particle-size control of the nanoparticles should be considered simultaneously. In the current study, Gd-diethylenetriaminepentaacetate(Gd-DTPA) was incorporated into layered double hydroxide (LDH) to meet the physicochemical properties required for MR-CT dual contrasting nanomedicine. Strategically, the particle size and nanometer incorporation of Gd-DTPA into LDH (GL-R hybrid) were controlled homogeneously using the reverse micelle method. X-ray diffraction showed that the hybrid obtained possessed a hydrotalcite phase. Dynamic light scattering and electron microscopic analyses showed that the hybrid had a controlled size of <200 nm with significant homogeneity. Fast Fourier-transform of transmission electron microscopy confirmed that the platelets of the GL-R hybrids were oriented randomly to form inter-particle space, enabling the Gd-DTPA moiety to be encapsulated stably. The encapsulation efficiency of Gd-DTPA was 20.8%, which was sufficiently high compared with other Gd-DTPA-incorporatedLDH. According to X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy, Gd-DTPA incorporated in the hybrid preserved its structure intact. Its potential as a dual modal contrast agent was demonstrated by measuring the concentration-dependent Hounsfield unit and magnetic resonance relaxivity, which were determined to be 230 at 2 mg/mL and 5.8 in the range ~0.2–1 mM-Gd, respectively.
This article examines the synoptic saying on serving two masters (Matt 6.24; Luke 16.13) in light of the evidence for jointly owned slaves in documentary papyri. The saying implies that the slave of two masters will inevitably be more loyal or exclusively loyal to one master. Scholars usually accept this as an accurate depiction of jointly owned slaves. However, the papyrological evidence shows that the relationship between jointly owned slaves and their owners varied in everyday life and that slaves had little control over their loyalty to each master. The saying is, therefore, not a fully realistic portrait of how jointly owned slaves served their masters in antiquity but is possibly a slave stereotype that contributes to the (un)faithful slave imageries in the Gospels.
The effect of exposure to repository-like conditions on compacted Wyoming bentonite was determined by comparing the hydraulic, mechanical, and mineralogical properties of samples from the bentonite buffer of the Canister Retrieval Test (CRT) with those of reference material. The CRT, located at the Swedish Äspö Hard Rock Laboratory (HRL), was a full-scale field experiment simulating conditions relevant for the Swedish, so called KBS-3, concept for disposal of high-level radioactive waste in crystalline host rock. The compacted bentonite, surrounding a copper canister equipped with heaters, had been subjected to heating at temperatures up to 95°C and hydration by natural Na-Ca-Cl type groundwater for almost 5 y at the time of retrieval.
Under the thermal and hydration gradients that prevailed during the test, sulfate in the bentonite was redistributed and accumulated as anhydrite close to the canister. The major change in the exchangeable cation pool was a loss in Mg in the outer parts of the blocks, suggesting replacement of Mg mainly by Ca along with the hydration with groundwater. Close to the Cu canister, small amounts of Cu were incorporated into the bentonite. A reduction of strain at failure was observed in the innermost part of the bentonite buffer, but no influence was noted on the shear strength. No change in swelling pressure was observed, while a modest decrease in hydraulic conductivity was found for the samples with the highest densities. No coupling was found between these changes in the hydro-mechanical properties and the montmorillonite — the X-ray diffraction characteristics, the cation exchange properties, and the average crystal chemistry of the Na-converted <1 μm fractions provided no evidence of any chemical/structural changes in the montmorillonite after the 5 y hydrothermal test.
Hydrothermal syntheses of a silicate structure comprising a single tetrahedral layer, known as ilerite, were conducted in the presence of tin (SnCl4·5H2O) as a heteroatom. The main aim of the study was to investigate the influence of the above-mentioned compound on the resulting material, as well as the possibility of isomorphous replacement of Si by Sn atoms. For comparison, unmodified ilerite, ilerite impregnated by SnO2, and ilerite synthesized in the presence of Al (aluminum isopropoxide) were also used. The ilerite structure observed was that of Na-ilerite. Syntheses of samples with various Sn/Si ratios (up to the value of 0.01Sn/4Si) and Al/Si ratios (up to the value of 0.005Al/4Si) resulted in a magadiite structure. Synthesis methods applied to Sn-modified materials were found to be unsuitable for the introduction of tetrahedrally substituted Al. The characterization methods used were X-ray diffraction (XRD), temperature-programmed reduction (TPR), and diffuse reflectance infrared fourier transform (DRIFT) spectroscopy. and these indicated the presence of metal oxide species on the surfaces of the crystals, in addition to a small degree of replacement of Si by Sn or Al in the tetrahedral layers.
Organo-montmorillonite (OMnt) has wide applications in paints, clay-polymer nanocomposites, biomaterials, etc. In most cases, the dispersibility and swellability of OMnt dictate the performance of OMnt in the target products. Previous studies have revealed that the properties can be improved when multiple organic species are co-introduced into the interlayer space of montmorillonite (Mnt). In the present study, single surfactant erucylamide (EA), dual-surfactants cetyltrimethyl ammonium bromide (CTAB) and octadecyltrimethyl ammonium chloride (OTAC), and ternary-surfactants EA, CTAB, and OTAC were co-introduced into Mnt by solution intercalation. The resulting OMnts were characterized by powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetry-differential thermogravimetry (TG-DTG), water contact-angle tests, scanning electronic microscopy (SEM), laser particle-size analysis, and swelling indices. Mnt co-modified by ternary CTAB, OTAC, and EA led to a large d001 value (4.20 nm), surface hydrophobicity with a contact angle of 95.6°, swellability (50 mL/g) with small average particle sizes (2.1−2.8 μm) in xylene, and >99% of the OMnt particles were kept as <5 μm in deionized water. The formation of EA-modified-Mnt was proposed according to hydrophobic affinity, hydrogen bonding, and van der Waals forces. The nanoplatelets of the CTA+, OTA+, and EA co-modified OMnts in xylene were assembled into a house-of-cards structure by face-to-edge and edge-to-edge associations. The electrostatic attractions, electrostatic and steric repulsions, and hydrophobic interactions were responsible for the good dispersibility of OMnt in xylene. The ternary surfactant co-modified OMnt with high dispersion and swellability will make OMnt better suited for real-world applications.
Vessel trajectories from the Automatic Identification System (AIS) play an important role in maritime traffic management, but a drawback is the huge amount of memory occupation which thus results in a low speed of data acquisition in maritime applications due to a large number of scattered data. This paper proposes a novel online vessel trajectory compression method based on the Improved Open Window (IOPW) algorithm. The proposed method compresses vessel trajectory instantly according to vessel coordinates along with a timestamp driven by the AIS data. In particular, we adopt the weighted Euclidean distance (WED), fusing the perpendicular Euclidean distance (PED) and synchronous Euclidean distance (SED) in IOPW to improve the robustness. The realistic AIS-based vessel trajectories are used to illustrate the proposed model by comparing it with five traditional trajectory compression methods. The experimental results reveal that the proposed method could effectively maintain the important trajectory features and significantly reduce the rate of distance loss during the online compression of vessel trajectories.
The conversion of volcanic glass to secondary alteration products is one of the most common mineralogical transformations during low-temperature hydrothermal alteration of submarine basalts. To better understand the mechanism and kinetics of this transformation, porphyritic and formerly glassy trachybasalt, recovered from Conical Seamount, Papua New Guinea, was studied in detail. Low-temperature interaction of trachybasalt with hydrothermal fluids at this submerged volcano occurred in response to the formation of submarine epithermal-style gold mineralization. Alteration of the coherent volcanic rocks is heterogeneous with pronounced differences in alteration intensity occurring between igneous minerals and the surrounding glassy groundmass. In comparison to the volcanic glass, the crystalline phases were less prone to hydrothermal alteration with the alteration susceptibility decreasing from clinopyroxene through biotite to feldspar. Low-temperature alteration of clinopyroxene resulted in the formation of abundant saponite-like smectite with no topotactic relationship being observed between the two phases. In contrast, the conversion of biotite to smectite involved structural inheritance as the orientation of common structural blocks was maintained during alteration. Transmission and analytical electron microscopy revealed that pervasive alteration of interstitial glass in the groundmass of the trachybasalt resulted in the formation of montmorillonite- and saponite-like smectite whereby smectite composition is strongly influenced by the glass chemistry. The occurrence of poorly crystalline domains with a 0.3 to 0.4 nm layer spacing in the altered interstitial glass suggests that the transformation of glass to smectite involved the formation of a transitional alteration product. Comparison with the results of previous studies highlights the fact that the glass-to-smectite transformation can proceed through more than one reaction pathway. Reaction style and reaction progress are controlled by kinetic factors such as the mode of fluid transport triggering alteration in the low-temperature hydrothermal environment. Alteration of the trachybasalt at Conical Seamount is inferred to have taken place at a comparably low fluid-rock ratio as the low permeability and the absence of primary fractures and joints restricted fluid circulation through the coherent volcanic rocks.
The presence, percentage, origins, and rate of formation of clay minerals have been important components in studies involving the geochemical and structural composition of waste-rock piles. The objective of the present study was to investigate the use of tritium as an indicator of the origin of clay minerals within such piles. Tritium values in pore water, interlayer water, and structural hydroxyl sites of clay minerals were examined to evaluate the origins of clay minerals within waste-rock piles located near Questa, New Mexico. Five clay minerals were identified: kaolinite, chlorite, illite, smectite, and mixedlayer illite-smectite, along with the hydrous sulfate minerals gypsum and jarosite. Analysis of waters derived from clay minerals was achieved by thermal reaction of dry-sieved bulk material obtained from the Questa site. In all Questa samples, the low-temperature water derived from pore-water and interlayer sites, as well as the intermediate-temperature water derived from interlayer cation sites occupied by hydronium and structural hydroxyl ions, show tritium values at or near modern levels for precipitation. Pore water and interlayer water ranged from 5.31 to 12.19 tritium units (TU) and interlayer hydronium and structurally derived water ranged from 3.92 to 7.93 TU. Tritium levels for local precipitation ranged from ~4 to 8 TU. One tritium unit (TU) represents one molecule of 3H1HO in 1018 molecules of 1H1HO. The elevated levels of tritium in structural sites can be accounted for by thermal incorporation of significant amounts of hydronium ions in interlayer cation sites for illite and mixed-layer clays, both common at the Questa site. In low-pH environments, such as those found within Questa waste-rock piles (typically pH ~3), the hydronium ion is an abundant species in the rock-pile pore-water system.
The fluoride ion is crystal chemically very similar to the hydroxyl ion, substituting for hydroxyl in many minerals in which hydrogen bonding is not important. Fluoride substitutions are particularly common in 2:1 layer silicates, such as micas, illites and smectites. The brick and tile industries, which use naturally occurring clays as their primary raw materials, have devoted considerable effort to understanding fluorine evolution during firing of the raw materials due to increasingly stringent fluorine emission regulations. In order to understand fluorine evolution from ceramic raw materials, we have studied a number of phyllosilicate materials used in making bricks. X-ray powder diffraction and fluorine analyses were combined with heating experiments and thermogravimetric analysis to evaluate the chemical and structural changes taking place on heating. Fluorine remained in 2:1 layer silicates to higher temperatures than did hydroxyl, but it behaved identically to hydroxyl in the kaolinite studied. In all cases, fluorine evolution coincided with structural breakdown of the clay host. These results show that fluorine evolution will consistently occur during firing of clay raw materials, and the problems of fluorine emission cannot be readily solved by simple variations of firing temperatures or times.
Rebels regularly provide public services, especially legal services, but the consequences of such programs are unclear. We argue that rebel courts can boost civilian support for insurgency and augment attack capacity by increasing the legitimacy of the rebellion, creating a vested interest in rebel rule, or enabling rebel coercion of the civilian population. We study the impact of the Taliban's judiciary by leveraging cross-district and over-time variation in exposure to Taliban courts using a trajectory-balancing design. We find that rebel courts reduced civilian support for the government and increased it for the Taliban, and were associated with more attacks and more coalition casualties. Exploring mechanisms, we find that courts resolved major interpersonal disputes between civilians but also facilitated more insurgent intimidation of civilians, and that changes in public opinion are unlikely to have been driven solely by social desirability bias. Our findings help explain the logic of rebel courts and highlight the complex interactions between warfare and institutional development in weak states.
To determine the relationships between the symmetry of the overall pyrophyllite and talc structure and the symmetry of individual layers, the geometry and symmetry of each 2:1 layer of pyrophyllite and talc were analyzed. For each, the previously published, refined unit cell may be rotated clockwise by ~60° for comparison to a layer unit cell. In pyrophyllite, the layer unit cell is ideal and shown to be orthogonal with C2/m symmetry. The agreement between the refined atomic coordinates and those calculated for the layer with C2/m symmetry confirms that the symmetry of the pyrophyllite layer is C2/m. The obliquity of the pyrophyllite refined cell results from the layer stacking and the choice of unit cell, but the interlayer stacking sequence does not disturb the layer symmetry. In contrast, talc has an oblique layer cell, without a mirror plane. For the most part, the distortion of the talc 2:1 layer is probably caused by an elongation of unshared O-O lateral edges around M1 that creates a slight corrugation of the octahedral sheet surface. Perhaps of lesser importance, the distortion of the talc layer cell may result from Coulombic interactions between cations of adjacent layers, and these cation-to-cation distances are sufficiently large (~6–7.5 Å) that the weak van der Waals forces that stabilize the stacking are not overcome. Because pyrophyllite has a vacant octahedral site, similar interactions are not present, and this results in a more idealized layer symmetry.
Phyllosilicates consisting of layers with an orthogonal cell and mirror plane (pyrophyllite, kaolinite, sudoite) were shown to have similar stacking faults. In these structures, the 2:1 or 1:1 layers have uniform orientation, and stacking faults occur owing to interstratifications of two alternative interlayer displacements in the same crystal that are related by a mirror plane in the projection on the (001) plane. In talc, stacking faults are associated with layer rotations by ±120°, whereas the lateral displacement between the adjacent tetrahedral sheets across the interlayer region is relatively ordered.