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The failure assessment diagram (FAD) is the most widely used method for analyzing the reliability of structure containing crack defect. In practical engineering, the failure assessment point (FAP) and failure assessment curve (FAC) are impossible to be determined accurately. Therefore, an interval failure assessment diagram (IFAD) method is proposed in this paper to analyze the reliability of structure containing crack defect when the FAP and FAC cannot be obtained accurately. Firstly, based on the interval method and FAD method, an interval failure assessment diagram (IFAD) model is established by considering the FAP and the failure critical point (FCP) as interval variables. And then the FAP and FCP intervals are converted into the normalized region to design the IFAD reliability index ηaccording to the relationship between the limit state function and the normalized region. The structural arbitrary state can be described by the IFAD reliability index η∈[0,+∞). In addition, 10 cases are given as examples to clearly expound the IFAD method, and the analysis results are compared with the FAD method, which confirms that the IFAD method is feasible and valid to analyze the structural reliability with the bounds of FAP and FCP. Finally, the IFAD reliability analysis of a certain propellant storage tank ellipsoidal bottom containing surface crack is taken as an application example to verify the practicability of the proposed method. And the results show that the IFAD reliability index can be obtained without the exact value of parameters.

Tesla valves are widely used in the field of fluid control. To study the hydraulic performance of straight-through Tesla valves in forward and reverse flow, 16 straight-through Tesla valves with diverse blade parameters were designed in this paper, and hydraulic loss tests were carried out in forward and reverse flow under different working conditions. The results show that the hydraulic loss increases with the increasing working flow rate in forward and reverse flow; at the identical flow rate, the reverse loss is higher than the forward loss. Both the hydraulic loss through the valve and the unidirectional conductivity of the valve increase with increasing blade length, pitch, and number of blades, but too long of a length results in weakened unidirectional conductivity. The hydraulic loss increases with the increase of blade angle, and the unidirectional conductivity decreases with the increase of blade angle. When the blades are arranged in perfect symmetry, the hydraulic loss through the valve is maximum, and the valve has the best unidirectional conductivity.

Human pepsin is a digestive protease that plays an important role in the human digestive system. The secondary structure of human pepsin determines its bioactivity. Therefore, an in-depth understanding of human pepsin secondary structure changes is particularly important for the further improvement of the efficiency of human pepsin biological function. However, the complexity and diversity of the human pepsin secondary structure make its analysis difficult. Herein, a convenient method has been developed to quickly detect the secondary structure of human pepsin using a portable Raman spectrometer. According to the change of surface-enhanced Raman spectroscopy (SERS) signal intensity and activity of human pepsin at different pH values, we analyze the change of the human pepsin secondary structure. The results show that the content of the β-sheet gradually increased with the increase in the pH in the active range, which is in good agreement with circular dichroism (CD) measurements. The change of the secondary structure improves the sensitivity of human pepsin SERS detection. Meanwhile, human pepsin is a commonly used disease marker for the noninvasive diagnosis of gastroesophageal reflux disease (GERD); the detection limit of human pepsin we obtained is 2 μg/mL by the abovementioned method. The real clinical detection scenario is also simulated by spiking pepsin solution in saliva, and the standard recovery rate is 80.7–92.3%. These results show the great prospect of our method in studying the protein secondary structure and furthermore promote the application of SERS in clinical diagnosis.

The adhesion coefficients of a bisectional road have significant coupled influences on the shimmy characteristics of the front wheels of a vehicle. A four-degree-of-freedom model for a representative sport utility vehicle was established. This model considered the adhesion coefficients of a bisectional road and the friction of the steering system of the suspension. The existence and stability of the system’s limit cycles were qualitatively determined using the Hopf bifurcation theorem and the centre manifold theory based on the model. The influences of the adhesion coefficients on the Hopf bifurcation characteristics of the system were calculated using a numerical method. The results showed that the road adhesion coefficient μ1of the left front wheel and the road coefficient μ2of the right front wheel significantly affected the vehicle shimmy and coupling relationship when different. Keeping μ1at a certain value, the swing angles and the angular velocities of the two front wheels consistently decreased when μ2decreased. The phenomenon repeatedly occurred when the difference Δμbetween the adhesion coefficients increased. Moreover, the discrepancy between the amplitude of the left front wheel and the amplitude of the right front wheel is much more apparent when both the adhesion coefficients are larger. Good agreement between the shimmy characteristics of the two wheels was also found when comparing the results using the centre manifold reduced-dimensions method with the numerical method. Furthermore, a higher reduced order caused the reduced system to be closer to the original system.

The adsorption isotherms and structural evolution of alkyl quaternary ammonium bromide (CnTAB) on graphite oxide (GO) were measured by means of an elemental analyzer, X-ray diffraction and Fourier transform infrared spectroscopy. In order to interpret the adsorption mechanism of surfactants onto GO, the adsorption kinetics and thermodynamics were further investigated. It was found that GO is a relatively efficient adsorbent within a wide range of temperatures (297–353 K), and the CnTAB was intercalated and then agglomerated into the interlayer spacing of GO via ionic bonding and hydrophobic bonding. The saturation amount of alkyl ammonium adsorbed on GO was decreased with the rise in temperature, and the experimental data fitted well into the modified Langmuir (Langmuir-Freundlich) equation. In addition, the negative values of ΔGand ΔHshowed that the adsorption process of CnTAB onto the GO was spontaneous and exothermic.

As a new type of non-metallic mineral resource, serpentine has attracted more and more attentions. Serpentine mineral resources are abundant in China, with more than 5 billion tons reserves proved. However, most of them have not been used adequately except for some special serpentine, such as serpentine jade and chrysotile. The overview for status quo of serpentine utilization consists of the distribution, chemical compositions, crystal structure of serpentine, mature but not economic applications and some development of high-value utilization research. It is expected to provide some references for deeper research and promoting its applications.

Spherical calcium carbonate (CaCO3) is a potential component in many industrial fields such as high-grade papermaking, high-grade painting, environment, and pesticide. This paper describes a novel approach to synthesize spherical calcium carbonate (CaCO3) particles via passing CO2 bubbles into phosphogypsum salt leaching solution (CaSO4) in the presence of ammonia (NH3) at different temperatures. The influence of the initial solution pH and concentration of calcium ions on the polymorph and morphology of CaCO3 was studied. The physical characteristics of the precipitate were evaluated using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that compared with different calcium sources the phase and morphology of CaCO3 synthesized by phosphogysum leaching solution had some regularity. The grain size of spherical CaCO3 became bigger, surface became smoother, and particle dispersion became better with the increase of calcium ion concentration. The content of vaterite increased and particle grain size changed a little with the increase of pH. The research results had important environmental significance for phosphogysum resource utilization and CO2 fixation.

The fibri-form silica was successfully synthesized from the short chrysotile fibers by inorganic acid-leaching. X-ray fluorescence analysis (XRF), X-ray diffraction (XRD), thermogravimetry and differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR) and N2 adsorption isotherms were used to characterize the products. The results indicate that the fibri-form silica is a kind of noncrystalline material, and the content of SiO2 in the fibri-form silica is 98.30%. From 50°C to 1200°C, the structure of fibri-form silica is stable. The average diameter of single fiber range from 20 nm to 50nm and the lengths are 50nm to 3μm. The surface area and pore volume of fibri-form silica are 369.22m2/g and 0.43cc/g, respectively. And the size of pore diameters are different, is one of mesopore materials presenting high quality filler and catalyzer carrier.

The effect of particle size of natural graphite on the size and structure of graphene oxide (GO) was investigated by using natural flake graphite (NFG) with different particle size. GO was prepared by modified Hummers method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, laser scattering particle size distribution analyzer and Atom force microscopy (AFM) were used to identify the characteristics of NFG and GO. The results provide evidence of how the graphite particle size affects the oxidation process and sheet size of the GO. Varies size monolayer GO sheets could be produced from the graphite with different particle size. The sheet size of GO is much smaller than that of the graphite, and the sheet size reduced multiple is proportional to the graphite particle size. The smaller particle size graphite is easily to be oxidized for a higher concentration GO suspension, and for more defect in the structure. Thus, this study leads to a better understanding of the preparation process of GO and provides a way to produce GO in different sheet size suitable for different applications.

Fibri-form silica was extracted from short chrysotile fibers by mix-roasting with ammonium bisulfate. The fibri-form silica were characterized by X-ray fluorescence analysis (XRF), X-ray diffraction (XRD), thermogravimetry and differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR) and N2 adsorption isotherms. The results show that the fibri-form silica with disordered crystalline structure, but also in fibrous morphology. The surface area and pore volume of fibri-form silica are 181.66 m2/ g and 0.44 cc/ g, respectively. The structure of fibri-form silica is stable, no phase transformed from 50 to 1200 oC.

For the large air bearing capacity and high rigidity, the author put forward a kind of slit type guide rail which based on gas film clearance throttle,through establishing the guide physical model,fitting the gas film surface ,and building a flotation control equation, refering to the finite difference method and dichotomy,solved the gas film pressure distribution based on Matlab numerical calculation,analysed the bearing capacity of gas floating needle bar under different eccentricity and the stiffness.The results show that: the gas floating guide,if a slit’s width is 0.2 to 0.26,and the cumulative length of the slit for half of the perimeter of the inner surface,the slit intermittently arrange six along circumference,has the best static performance.The larger the needle bar eccentric,the bigger the flotation capacity and stiffness,it is capable of carrying the load of the needle bar,and the air tightness of the structure is good,throttling effect is obvious.

The benefits of climate adaptation policy are sometimes underestimated because its nonuse values perceived by people indirectly affected are usually ignored. Using data from a representative sample of Beijing’s urban population, it is shown that people living at a distance perceive nonuse values of climate change adaptation measures aimed at improving the environmental conditions in the Tarim River Basin in Northwest China. Using the contingent valuation method the monetized benefit of a particular set of climate adaptation measures experienced by a Beijing household is approximated. It is concluded that not only the preferences of local people, but also of people living in other parts of China should be considered when deciding if a climate adaptation policy is worthwhile implementing from a social welfare point of view.

In this study, discharge at the outlet of Xijiang River, the biggest sub-basin of the Zhujiang River, was simulated and projected from 1961 to 2099 using the hydrological model HBV-D. The model uses precipitation and temperature data from CISRO/MK3–5, MPI/ECHAM5, and NCAR/CCSM3 under three greenhouse gas emission scenarios (SRES A2, A1B, B1). The results in water resources and flood frequency suggest that annual precipitation and annual runoff would increase after 2050 relative to the reference period of 1961–1990. In addition, increasing trends have been projected in area averaged monthly precipitation and runoff from May to October, while decreasing trends in those from December to February. More often and larger floods would occur in future. Potential increase in runoff during the low-flow season could ease the pressure of water demand until 2030, but the increase in runoff in the high-flow season, with more often and larger floods, more pressure on flood control after 2050 is expected.

In this paper, a fine pure Magnesium aluminate spinel powder was synesised by Gel solid reaction,using Al(NO3)3 6H2O and Mg(NO3)26H2O as raw materials under given condition. The precursor was formed by polymer gelling.The phase changed according to heating temperatures from 700℃ to 900℃.The single phase of Magnesium aluminate spinel was obtained by calcining the precursor at temperatures higher than 900℃. The phase changing process and relationship among calcination parameters, phase composition and image of particle are studied to determine the optimal conditions for the synthesis of fine Magnesium aluminate spinel powder. The powder obtained was characterized by XRD,TEM etc. The results of analysis showed that the ultrafine powder is of spinel phase, high purity, good dispersion.This process for preparing fine Magnesium aluminate spinel powder was very simple and inexpensive.The results of analysis showed that the ultrafine powder was of mullite phase, high purity, good dispersion, and the particle were homogeneous.

First principles calculations were run on bulk and the （110）（001）（012）（113） surfaces of α-Al2O3 in order to examine the growth habit of α-Al2O3 crystals.The Materials Studio package was used, specifically the program CASTEP, utilizing Perdew Burke Ernzerh of exchange-correlation pseudo-potentials. The calculation results shows that the ranking of the face energy on different crystal face are E(001)‹ E(113) ‹ E(012) ‹E(110) which is in good agreement with experiment phenomenon observed that the ranking of the growth rates of different crystal faces are V(001) ‹ V(113) ‹ V(012) ‹ V(110).

determination of the optimum asphalt content usually associates the Marshall Index with volumetric parameters for hot mix asphalt (HMA). Because unreasonable volumetric parameters may result in the asphalt content being more or less so that performance of HMA are influenced. Therefore in this paper, relationships between volumetric parameters and the Marshall Index were studied for two kinds of gradations, AC25 and AC13, which for each kind of gradation, according to the orthogonal test method, the pass percentages of aggregate between the each sieve size and the usage of asphalt contents were changed to form 50 sets of asphalt mixtures for the Marshall test and the volumetric parameters experiment. The results show that rank of influence significance of volumetric parameters on the Marshall Index is Gmb and VV, then VMA and last VFA. However, for fine aggregate (AC13) asphalt mixtures, as Gmb increases, all the MS and the FL increase. Meanwhile, as VV increases, the MS and the FL of AC25 asphalt mixtures increase, whereas for AC13 asphalt mixtures the MS decreases but the FL increases. So for proportion design of fine aggregate (AC13) asphalt mixtures, the fine aggregate and the asphalt content must be strictly controlled to meet the VV requirement and to avoid asphalt pavements to become over-densified. In addition, with VMA increases, for course aggregate (AC25) asphalt mixtures, MS and FL increase, but for course aggregate (AC13) asphalt mixtures, MS decreases but FL increases. Otherwise, the influence of VFA on MS and FL could be nearly ignored.

By utilizing chrysotile asbestos tailing from Shannan ore in Sichuan as the main raw material, diopside-based glass-ceramics were successfully synthesized in the laboratory by adding some limestone, quartz sand, Al2O3, H3BO3, Na2CO3 and CaF2. The optimum procedure for glass-ceramics was as follows: melting at 1400 for 60 min, sintering at 1100 for 120 min. Through the tests of physical and mechanical properties, the glass-ceramics materials with more crystalline phase had high density, fine performance of resisting compression (366MPa) and negligible water absorption. Through chemical resistance tests, the glass-ceramics samples showed strong corrosion resistance. Overall result indicated that it was a feasible attempt to produce glass-ceramics materials for building and decorative materials from chrysotile asbestos tailing.

Stator winding inter turn short-circuit fault is one of the most common internal faults of fault-tolerant machine, which can disconnect the fault phases and keep operating correctly in the event of a failure. Stator winding short-circuit fault model is established through analysis. Based on finite element method, the high-power density fault-tolerant machine internal magnetic field simulation and analysis is implemented using Maxwell2D and induced voltage frequency spectrum is analyzed by FFT method. The characteristics of stator winding short-circuit faults are summarized, which lay a solid foundation for fault-tolerant machine earlier faults prediction and winding switching.

Graphite oxide samples with different oxidation levels were prepared by the oxidation of natural flake graphite based on a modified Hummers method, using different reaction temperatures and oxidation times followed by ultrasonication then centrifugation to obtain the corresponding graphene oxide nanosheet suspensions. The samples were characterized by XRD and AFM. The results show that the oxidation level of graphite oxide samples can be increased by increasing either the reaction temperature or the oxidation time. Well-dispersed suspensions of the graphite oxide samples can be formed in alkaline solution after ultrasonication, especially for samples with higher oxidation levels. A number of coarse particles are observed in the suspensions, particularly those derived from graphite oxide samples with lower oxidation levels, due to the lower degree of exfoliation in these samples, which is influenced by the oxidation level. Rapid sedimentation of these coarse particles can be achieved by high-speed centrifugation, yielding homogenous suspensions of graphite oxide comprising a mass of monolayer graphene oxide nanosheets with lateral dimensions of several hundred nanometers to several micrometers and thickness of ~1.0–1.4 nm.

The effective chlorolactonization of alkenoic acids with (diacetoxyiodo)benzene and lithium chloride under mild conditions have been studied. Experiments show that various 4-pentenoic acids react with (diacetoxyiodo)benzene and lithium chloride fluently in CH3OH at room temperature, obtaining five-membered chlorolactones in good yields in short times. Other alkenoic acids, such as 3-butenoic acid and trans3-hexenoic acid give some more complicated results, and 4-pentynoic acid provides a chloroenol lactone with Zconfiguration in 40% of yield.

. In order to exploit a kind of low cost and environment-friendly humidity sensing materials, a series of Li-modified montmorillonite ion conductors were prepared using the montmorillonite form Jimusaer in Xinjiang Province of China. The montmorillonite humidity sensing elements were made by the thick film technique on mica substrates. Then the structures of the samples were investigated by X-ray diffraction (XRD) and the humidity sensing characteristics of the elements were tested by an equipment of the resistance testing. The results indicate that the resistances of the montmorillonite humidity elements all decrease with the increase of the system humidity. But there is a great discrepancy between the resistances of Na- montmorillonite humidity element when humidity adsorption and desorption. It was found that Li-modification montmorillonite ion conductors behave well as a humidity sensing material in 30～90% RH (relative humidity). The suitable experimental parameters of montmorillonite Li-modifying under ~ 80℃are obtained.

Hydrophlogopite was modified with sodium and then organically intercalated with a series of alkyl quaternary ammonium salts. The organically intercalated samples were characterized by X-ray diffraction analysis (XRD) and the effect of alkyl quaternary ammonium salt on the interlayer spacing of hydrophlogopite was discussed. The results showed that if the same alkyl quaternary ammonium salt was used to intercalate hydrophlogopite, the interlayer spacing of hydrophlogopite increased gradually with the rise of the added amount of quaternary ammonium salt, and that if different quaternary ammonium salts with the same amount were used, the interlayer spacing increased gradually with the rise of the chain length of the alkyl quaternary ammonium salts. For the alkyl quaternary ammonium salts with large chain length (n>10), the inflection point for the increasing interlayer spacing of the intercalated hydrophlogopite is at about 0.5 times of CEC. When octadecyl trimethyl ammonium bromide is used as intercalation agent and the added amount is 5 times of CEC, the interlayer spacing of hydrophlogopite is relatively maximal.

Chrysotile asbestos tailing was broken down into active magnesium oxide and silicon dioxide by roasting. The activation product of Chrysotile as raw materials was used to prepare acicular basic magnesium carbonate by the carbon–ammonia method. The effect of the carbonization temperature, aging temperature, aging time, and the mole ratio of NH3•H2O and Mg2+ were studied on the form and percent conversion of the acicular basic magnesium carbonate. The structure, thermal properties and crystal morphology of the sample were analyzed by XRD analysis, thermal analysis and optical microscope, respectively. The results show that acicular basic magnesium carbonate prepared at the best conditions: carbonization temperature is at 50℃, aging temperature is at 70℃, aging time is for 4-5 hours, and the molar ratio of NH3•H2O and Mg2+ is 2:1. In this condition, the formation rate of specula basic magnesium carbonate is more than 82%. Its chemical formula which is 4MgCO3•Mg(OH)2•4H2O is obtained by XRD and thermal analysis, and the aspect ratio of the sample of the acicular basic magnesium carbonate was about 30 which was tested by optical microscope.

In this paper, thermal insulation boards comprising expanded vermiculite and gypsum were manufactured by casting and compression molding methods respectively. The effects of flake size and preparation methods of expanded vermiculite (EV), ratio of calcined gypsum/EV and molding methods on thermal and mechanical properties were discussed. The results indicated that the thermal conductivity (λ) and compressive strength of the boards decreased with the increase of flake size, and increased as the ratio of calcined gypsum/EV rose, and the density of the boards increased linearly with the increasing ratio. Compared to compression molding, casting technique can make insulating materials with higher thermal conductivity, compressive strength, and lower water content. The boards containing EV expanded by microwave chemical method presented a better thermal insulating property (λ=0.091W•m-1•K-1) relative to the ones filled with microwave exfoliated EV (λ=0.107W•m-1•K-1). The prepared materials can be used for heat, acoustical insulation and moisture adjustment.

Based on cationic exchange and adsorption properties of industrial vermiculites, acid-activation processing and decoloration rate testing for industrial raw vermiculite samples industrial vermiculite samples from the Yuli Mine in Xinjiang Uygur Autonomous Region were researched. Some factors that influenced the acid-activated products adsorption and the decolorization performance were investigated, such as acid concentration, activation time, activation temperature etc., and optimum process conditions were developed as follows: the acid concentration was 3.0 mol/L, the activation time was 3 h and the activation temperature was 90℃, under these conditions, the decoloration rate of acid-activated sample was 88.46%.

Based on the crystal chemistry characteristics of industrial vermiculite, the application mineralogy characteristics of the industrial vermiculite samples from four Mines in China have been studied. The results show that the samples are composed of phlogopite-vermiculite and chlorite-vermiculite interstratified minerals. The interstratified structure characteristics and the vermiculite layer contents are different in the different samples even for the samples from same Mine. The chemical compositions have difference in the different interstratified structure type samples. The contents of K2O, TiO2 and Na2O are higher for the samples with phlogopite-vermiculite interstratified structure and the contents of MgO and Al2O3 are higher for the samples with Chlorite-vermiculite interstratified structure. The cation exchange capacities of the samples are between 17.26mmol/100g and 98.95mmol/100g. The thermal expanding ratios of the samples are between 9 and 32. The samples with more vermiculite layers have bigger cation exchange capacity and the thermal expanding ratios.

A series of polyaniline/vermiculite nanocomposites was synthesized. The interlayer space of vermiculite was initially increased by the insertion of dioctadecyl dimethyl ammonium bromide, and then the aniline monomers were inserted into the interlayer space of vermiculite replacing dioctadecyl dimethyl ammonium cations. The polyaniline/vermiculite nanocomposites materials were prepared via in situ polymerization of the aniline monomers in the interlayer space of vermiculite. The as-synthesized polyaniline/vermiculite nanocomposite materials were characterized by X-ray diffraction analysis, infrared spectroscopy, and electrical conductivity measurement. The results indicated that the vermiculite was peeled off into the polyaniline. The introduction of vermiculite nanosheets showed a beneficial effect on the electrical conductivity of polyaniline.

Based on the characters of expanding and layer adsorbing of vermiculite，industrial vermiculite samples from Weili Mine of Xinjiang Province were expanded by both chemical and microwave chemical methods. The influences to the exfoliation ratio of different parameters such as concentration of hydrogen peroxide, power of the microwave, heating time, ratio of solid-liquid, immersion time were discussed. And the expanded mechanism of vermiculite was also analyzed. The results indicate that the expanded times increase with the increasing of concentration of hydrogen peroxide, and the best expanding point appears when the concentration of hydrogen peroxide is 30%. The solid-liquid ratio of vermiculite and hydrogen peroxide has little effect on the expanding of vermiculite. The vermiculite samples could be expanded 8.5 times by heated 2 min under 800W microwave power after immersion for 12 h when the concentration of hydrogen peroxide is 30%. As a result, the vermiculite could be expanded because of the oxygen pressure produced by the decomposition of hydrogen peroxide into the vermiculite interlayer. When using the microwave chemical method, the pressure of both oxygen and interlayer water lead to the increases of the expanded times. And exfoliation vermiculite plays an important part in energy-saving and environmental treatment.

In order to improve the gas sensitivity of SnO2, Ni-doped and Co-doped nano-powders were prepared by the homogenous co-precipitation method using analytical pure SnCl4•5H2O and NH3•H2O as main materials under different doped ratios n (M2+)/n (Sn4+). The gas sensors were made by the thick film technique on mica substrates. The structure and crystal properties of the samples were investigated by X-ray diffraction (XRD). The results indicated that Sn4+ in the crystal lattice of SnO2 was partly replaced by M2+, which resulted in the change of the M-O bond lengths and the lattice parameters. The sensitivities of the sensors in H2 atmosphere with different concentrations at 75°C were tested. As a result, doped M2+ especially Ni2+ improves its H2 sensitivity, the sensitivities increases linearly with the increasing H2 concentration, and the best doping n(M2+)/n(Sn4+) of preparing gas-sensing material were obtained. The results show that doping which leads to the asymmetry of electrovalent balance of M-O octahedrons improves the activities and semiconductor properties of the powders. These studies play an important part in detecting reductive gases in special environment.

Hydrophlogopite, a regular interstratified mineral with 1:1 ratio of vermiculite and phlogopite crystal layers, was modified with sodium and organically intercalated with HDTMAB, and then the samples were examined with XRD. Based on the theoretical geometric dimensions of organic cations, the structure and arrangement model of HDTMA+ cation in the interlayer space of vermiculite crystal layers were studied, the reaction mechanism of organic intercalation was also discussed. The results show that HDTMA+ cations enter into the interlayer space of vermiculite crystal layers only without exchange with the cations in the interlayer space of phlogopite crystal layers, and that the arrangement models of HDTMA+ cations in the interlayer space of vermiculite crystal layers varies with the added amount of HDTMAB. When the added amount is small, the arrangement model of HDTMA+ cations in the interlayer space of vermiculite crystal layers is lateral-bilayer, and when the added amount is larger, the arrangement model is paraffin-type monolayer.

Based on good cation exchange property of vermiculite，the adsorption of vermiculite for simulated radionuclide Sr was studied by the static adsorption method. The adsorption behaviors and the effect of the experimental conditions were investigated. The results show that the saturated adsorption capacity of vermiculite sample for the simulated radionuclide Sr was 8.246×10-2 mmol/g. The suitable pH value ranged from 4 to 11, the balanceable adsorption time was 3d, and the suitable temperature was 30℃. The main adsorption type was cation exchange. The adsorption mechanism can be described by Langmuir and Freundlich models. It acts better in accord with Langmuir model, and the correlation coefficient is 0.99974. This experimental study has important significance on low concentration of Sr radioactive waste liquid treatment.

The monthly, seasonal, and annual precipitation trends in the Yangtze river catchment have been detected through analysis of 51 meteorological stations’ data between 1950–2002 provided by National Meteorological Administration. Results reveal that: 1) Summer precipitation in the Yangtze river catchment shows significant increasing tendency. The Poyanghu lake basin, Dongtinghu lake basin and Taihu lake basin in the middle and lower reaches are the places showing significant positive trends. Summer precipitation in the middle and lower reaches experienced an abrupt change in the year 1992; 2) The monthly precipitation in months just adjoining to summer shows decreasing tendency in the Yangtze river catchment. The upper and middle reaches in Jialingjiang river basin and Hanshui river basin are the places showing significant negative trends; 3) Extreme precipitation events show an increasing tendency in most places, especially in the middle and lower reaches of the Yangtze river catchment.

In this study the arable land changes in two counties (Zigui and Xingshan) in the Three Gorges Reservoir area in China are investigated. The statistical data from the officially published statistical books are used to study these changes in the two counties during the past 50 years since 1949. The changes of arable land, changes of arable land per capita, and changes of multiple crop index in Zigui and Xingshan counties are examined. Using an index method, we conclude that the two counties are critical in the sustainable utilization of arable land.

With laser scanning confocal fluorescence microscopy, we demonstrate a novel type of morphology evolution in moderately thick films (70–100 μm) of ternary blends of polypropylene (PP), polyethylene (PE), and ethylene–propylene rubber (EPR), in which EPR is labeled with a benzothioxanthene dye (HY-EPR). The blends are prepared by solution blending, and the phase morphology evolves during the annealing of the blend films in a stainless steel mold. Our results indicate that wetting of the mold surface is a driving force in morphology evolution for the two blend compositions investigated. For 81/14/5 PP/PE/HY-EPR, phase evolution within the mold results in a laminar structure and hydrodynamic channels, features which have previously been found in thin films of polymer blends as a result of surface-directed spinodal decomposition. In a blend with a lower weight fraction of the dispersed phase (92/7/1 PP/PE/HY-EPR), we find that the PE/HY-EPR domains are larger and more polydisperse closer to the surface because of wetting of the mold wall. We also show that the phase morphology in these films can be controlled by the nature of one or both of the surfaces being varied. When one of the mold surfaces is replaced with a thin film of PP homopolymer, we observe draining of PE/HY-EPR from the PP to the mold surface, which results in a bilayer structure. A trilayer morphology is likewise obtained by the replacement of both mold surfaces with PP. We also carry out three-dimensional image reconstruction on a single PE/HY-EPR particle within the 81/14/5 PP/PE/HY-EPR blend to obtain detailed information on the interphase structure. We find that HY-EPR of this composition (30/70 ethylene/propylene) fully coats the PE dispersed phase and partially penetrates the PE droplets. This result falls between the interphase structures found for previously investigated EPR compositions (40/60 and 80/20 ethylene/propylene). © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 637–654, 2003

The heavy floods in the Taihu Basin showed increasing trend in recent years. In this work, a typical area in the northern Taihu Basin was selected for flood risk analysis and potential flood losses assessment. Human activities have strong impact on the study area's flood situation (as affected by the polders built, deforestation, population increase, urbanization, etc.), and have made water level higher, flood duration shorter, and flood peaks sharper. Five years of different flood return periods [(1970), 5 (1962), 10 (1987), 20 (1954), 50 (1991)] were used to calculate the potential flood risk area and its losses. The potential flood risk map, economic losses, and flood-impacted population were also calculated. The study's main conclusions are: 1) Human activities have strongly changed the natural flood situation in the study area, increasing runoff and flooding; 2) The flood risk area is closely related with the precipitation center; 3) Polder construction has successfully protected land from flood, shortened the flood duration, and elevated water level in rivers outside the polders; 4) Economic and social development have caused flood losses to increase in recent years.

A thermoplastic olefin blend consisting of isotactic polypropylene (PP) and an ethylene-butene copolymer (EBR) impact modifier (25 wt % EBR) was subjected to a short, high-shear pulse within the flow channel of a pressure-driven microextruder following low-shear channel filling from a reservoir of the melt. The resulting morphology was examined by laser scanning confocal fluorescence microscopy (LSCFM), with contrast provided by a fluorescent tracer in the EBR minor phase. Shear experiments were performed under isothermal conditions with a known wall shear stress for a specified duration, providing a well-defined thermal and flow history. Low-shear channel filling produces small droplets across the central region of the channel and large droplets, consistent with steady-state shear, in the regions near the channel walls. After cooling the molten blend to a crystallization temperature of 153 °C, a brief interval (5 s ~ 1/2000 of the quiescent crystallization time) of high shear (wall shear stress: 0.1 MPa) induces rapid, highly oriented crystallization and a stratified morphology. Ex situ LSCFM reveals a “skin” at the channel walls (~70 μm) in which greatly elongated fiberlike droplets, oriented along the flow direction, are embedded in highly oriented crystalline PP. Further from the walls but directly beside the skin layers are surprising zones in which EBR domains show no deformation or orientation. Several zones of intermediate deformation and orientation at an angle to the flow direction are located closer to the center of the channel. At the center of the channel, EBR droplets are spherical, as expected for channel flow. The various strata are explained by the interplay of droplet deformation, breakup, and coalescence with the shear-induced crystallization kinetics of the matrix. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2842–2859, 2002

A benzothioxanthene-labeled ethylene-butene rubber has been synthesized and tested as a potential fluorescent tracer for the impact modifier (IM) phase in laser scanning confocal fluorescence microscopy (LSCFM) studies of thermoplastic olefin (TPO) morphology. The amino-functional Hostasol Yellow derivative HY-DP reacts with maleated EBR-28 to give a good labeling yield (ca. 70%) and a dye concentration of 0.051 mmol/g, when the maleated rubber is first refluxed over molecular sieves and the reaction purged with N2. Without pretreatment of the rubber and N2 purging, a lower labeling yield (0.036 mmol dye/g) is obtained and the labeled product tends to undergo crosslinking at 240 °C and subsequent dye detachment when the crosslinked gel is hydrolyzed. LSCFM studies reveal HY-labeled EBR to be completely miscible and evenly dispersed in the unlabeled EBR-9 of model TPO blends. Moreover, the HY-labeled EBR provides good fluorescence contrast between the IM droplets and the PP matrix in the TPO blend PP/EBR (80/20) (w/w) + 3 wt % labeled polymer with respect to EBR. Imaging of IM droplets down to 40 μm below the film surface of this blend has been demonstrated. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 239–252, 2001

Thermally‐induced self‐crosslinking behaviour has been found in copolymers containing N‐methyl‐N‐vinylbenzylpyrrolidinium chloride (MVBPC) and methyl methacrylate (MMA). NMR, IR and low molecular weight model reactions demonstrate that this crosslinking reaction occurs between the methyl ester groups of the MMA units and the quaternary ammonium salts, with the resulting benzyl esters forming chemical links between the MVBPC and MMA units with the formation of N,N‐dimethylpyrrolidinium chloride. Similar crosslinking behaviour has also been found when the Cl− anion is replaced by Br− and I−, but not in the case of BF−4 as counter anion.© 2000 Society of Chemical Industry

Focuses on the improvements in the economic situation of China brought about by its adoption of its macro-control measures in 1993. Features of macro control strategies by the Chinese government; Growth in the gross domestic product; Increase in the average income of urban and township residents; Economic growth rate; Industrial growth value.

Reports on the economic development of Jiangsu province in China. Industrial and agricultural output of Jiangsu province since 1978; Cities and geographical features; Foreign investments; Construction of the riparian economic belt; Infrastructure and township enterprises; Strategies to propel Jiangsu into the world economic orbit; Establishing the futures market in accordance with international standards.

Golgi–Cox method and morphometric analyses were used to study the plasticity of striatal medium spiny I neurons in 6-month-old C57BL/6N mice after unilateral or bilateral lesion of the cerebral cortex or combined lesions of the ipsilateral cerebral cortex and intralaminar thalamus. In adult mouse, unilateral lesions of the cerebral cortex did not result in a net gain or loss of linear dendritic length in a randomly selected population of striatal medium spiny I neurons. In addition, there was a well-defined time course of striatal spine loss and replacement occurring after a unilateral cortical lesion. By day 3 postlesion the average 20-μm dendritic segment had lost 30% of the unlesioned control spine value, reached its nadir, lost 45.5%, at 10 days postlesion, and recovered to 80% of unlesioned control levels by 20 days postlesion. The recovery of spines was blocked by a secondary lesion on the contralateral cortex but not on the ipsilateral intralaminar thalamus. These data suggest that striatal medium spiny I neurons of adult mice have a remarkable capacity for plasticity and reactive synaptogenesis following a decortication. The recovery of spine density is primarily induced by axonal sprouting of survival homologous afferent fibers from the contralateral cortex.

Ski tourism is extremely sensitive to climate change and is also heavily affected by socioeconomic conditions. Although some ski areas are still profitable under current climate and socioeconomic conditions, they will become difficult to operate in the face of rising winter temperatures, which will result in further economic losses, resource waste and environmental damage. This study projects variability in the suitability of ski area development across China in the coming decades. Natural suitability under three representative concentration pathway emission scenarios (RCP2.6, RCP4.5 and RCP8.5), socioeconomic suitability under four shared socioeconomic pathways (SSP1, SSP2, SSP3, and SSP5) and integrated suitability under four climatic-socioeconomic scenarios (RCP2.6-SSP1, RCP4.5-SSP2, RCP8.5-SSP3, and RCP8.5-SSP5) are reported. Furthermore, the suitability of 731 existing ski areas in China is assessed. The results show a substantial decline in integrated suitability for most regions of China except for some very cold areas, where higher air temperatures will make visitors feel more comfortable and the relatively poor socioeconomic conditions will improve in the 2030s, 2050s and 2090s. The average higher integrated suitability area (integrated suitability values greater than 0.5) under four climatic-socioeconomic scenarios decreases from the current 29.9% to 14.4%, 5.0% and 4.5% by the 2030s, 2050s and 2090s, respectively. Under RCP2.6-SSP1, the higher integrated suitability area is projected to decrease from the current 28.0% to 5.2% by the 2050s and then increase to 5.3% by the 2090s. Under RCP4.5-SSP2, RCP8.5-SSP3, and RCP8.5-SSP5, the higher integrated suitability area is projected to continuously decrease from 30.3%, 30.6% and 30.6% in the 2010s to 4.1%, 4.4% and 4.4% in the 2090s, respectively. By the 2090s, 41, 138 and 277 existing ski areas are projected to be closed under RCP2.6-SSP1, RCP4.5-SSP2, and RCP8.5-SSP3/RCP8.5-SSP5, respectively. It is clear that emission pathways and climate change adaptation and mitigation strategies will greatly shape the development of China’s regional ski tourism.

Chlorolactonization of various unsaturated acids under optimized conditions A) provides five‐membered chlorolactones under mild conditions.