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The Upper Paleozoic in the southwestern Ordos Basin has significant potential for natural gas exploration. This study investigated the diagenetic fluid evolution and hydrocarbon accumulation characteristics of He 8 section from Permian Lower Shihezi formation and Shan 1 section from Shanxi formation tight sandstone reservoirs by petrographic observation, scanning electron microscope imaging, fluid inclusion study, and laser Raman spectrum analysis. The results show that He 8 section and Shan 1 section reservoirs are mainly composed of quartz sandstone, subordinate arkose quartz sandstone, and lithic quartz sandstone, with minor lithic sandstone and lithic arkose sandstone. The major pores are intergranular dissolved pores. The main diagenetic minerals include quartz overgrowth, siliceous cement, carbonate cement, illite, montmorillonite, and mixed-layer clay minerals. The overall diagenetic features show strong compaction, multistage siliceous and calcareous cements, and abundant clay minerals, strong dissolution, and well-developed fractures. Two stages of fluid inclusions developed in the He 8 and Shan 1 sections recorded the migration and accumulation of the early-stage and late-stage natural gas, respectively. The reservoir in the study area experienced early and late diagenetic stages, and its formation was simultaneous with or after its densification. The diagenetic environment changed from alkaline to acidic and again into alkaline. There are two stages of fluid activities in the study area, namely, the early diagenetic stage corresponding to hydrocarbon generation and migration and the late diagenetic stage corresponding to hydrocarbon accumulation. This study suggests that Upper Paleozoic natural gas migrated into the reservoir in Weibei Uplift, Yishan Slope, and Tianhuan Depression tectonic units during 220-197 Ma, and the large-scale migration and accumulation occurred in these tectonic units at different times. No natural gas was generated in the west margin of the basin because the temperatures of the hydrocarbon source rocks in the Upper Paleozoic were below the gas window.

Iron is one of the most abundant elements on the surface of the earth (5.1%), but is rarely used for photocatalytic hydrogen production due to its unsuitable band structure. Herein, a ternary Z-scheme g-C3N4/rGO/FeOOH heterostructure photocatalyst for hydrogen production was designed and fabricated. Due to its narrow bandgap and a low oxygen evolution overpotential of FeOOH, the Z-scheme g-C3N4/rGO/FeOOH ternary heterojunction exhibited excellent photocatalytic hydrogen production with the yields of 124.9 and 869.8 μmol h−1 g−1 (244.9 and 107.4 times larger than that of pristine g-C3N4) under visible and UV-visible light irradiation, respectively. This work could expand the usage of the earth-abundant element for solar energy conversion and provide a new viewpoint for the development of high-performance photocatalysts through a rational design of the component of the heterostructure.

A rational design of the morphology and configuration of the photocatalyst heterostructure is of great importance for solar energy conversion. This work reported the uniform distribution of CdS nanoparticles over the MOF-derived porous NiO skeleton, thanks to the PVP surface modification, with the residual carbon acting as a conductive medium of charge carriers. The formation of CdS-porous NiO exhibited an excellent photocatalytic hydrogen evolution activity of 7.12 mmol h−1 g−1, and was further improved to 14.25 mmol h−1 g−1 after the PVP surface modification. Impressively, even in the absence of a sacrificial agent, the well-dispersed CdS–NiO heterostructure exhibited a photocatalytic hydrogen production activity of 29.92 and 6.83 μmol h−1 g−1 with the production of a considerable amount of H2O2 under UV-visible and visible light irradiation, respectively.

The g-C3N4-MoS2-M(OH)x ternary heterostructures were designed and fabricated for the first time. The embedding of noble-metal-free MoS2-M(OH)x dual cocatalysts over g-C3N4 nanosheets led to obvious synergistic effect for improving the transport as well as utilization efficiency of photo-generated charge carriers. Consequently, the optimal ternary heterostructure (g-C3N4-MoS2-Ni(OH)2) exhibited photocatalytic hydrogen production activity 4.5 times larger than the sum of the photocatalytic HER activity of g-C3N4-MoS2 and g-C3N4-Ni(OH)2. More significantly, even in the absence of the sacrificial agent, the g-C3N4-MoS2-Ni(OH)2 ternary heterostructure exhibited a photocatalytic HER activity of 0.3 mmol h-1 g-1 with considerable H2O2 production under UV-visible light.

The UV curable acrylamide-based suspension is an environmental material used for digital light processing (DLP) which is currently one of the most accurate additive manufacturing methods. In this paper, a high loaded and low viscosity silica suspension was developed based on acrylamide system, moreover, the influence of dispersant, solid loading and ball milling time on the rheological properties of silica suspensions was investigated. Furthermore, in order to understand the polymerization reaction process, the effect of photoinitiator concentration and ratio between monomer (AM) and the cross-linking agent (MBAM) on curing properties of silica suspension was discussed. Finally, following the study of rheological properties and curing characteristics, the testing results of sintered silica ceramics showed a density and flexural strength of 1.42 g/cm3 and 13.31 MPa at 1200 °C respectively.

Based on the element geochemistry and biomarkers of the oil shale from the Chang 7 sub-unit in the southern Ordos Basin, the depositional conditions and organic source of the oil shale are discussed. Biomarkers analyses show that the oil shale has a homologous organic matter source, with a mix of plankton and advanced plants. U/Th and V/Ni ratios suggest that the redox condition is dominated by a reducing condition, and the degree of anoxia in the Tongchuan area is higher than that of the Xunyi area. Sr/Ba ratios illustrate that the oil shale is deposited in fresh water and the paleosalinity in the Tongchuan area is slightly higher. Fe/Ti ratios imply that the Tongchuan area underwent obvious hydrothermal fluid activities. Sr/Cu ratios show warm and humid paleoclimate in both areas. As assessed by (La/Yb)NASC, the deposition rate in the Tongchuan area is relatively lower. Fe/Co and Th/U ratios suggest that the paleo-water-depth in the Tongchuan area is deeper. The source rock could have the advance plants source, which must have close relationship with the Qinling orogeny. Comparing the paleoenvironment, the Tongchuan area has better depositional conditions, and is the key oil shale exploration area in the southern Ordos Basin.

A novel series of CaZr4-xTixP6O24 ceramics based on sodium zirconium phosphate was prepared by the co-precipitation method. The effects of Ti4+ substitution for Zr4+ on the crystal structure, sintering characteristics, Raman spectra, and mechanical and thermophysical properties were examined. X-ray diffraction results indicated that all compositions exhibited a single phase with a rhombohedral structure. The Raman spectra revealed no significant changes with increasing Ti4+ content. The crystal structure was analysed by Rietveld refinement, and the lattice parameters were obtained with a satisfactory structural convergence of R-factors. Ti4+ substitution could effectively improve sinterability and reduce microcracks via decrease of the c/a ratio. The flexural strength and Vickers hardness monotonically increased to 58.63 MPa and 2.73 GPa, respectively. The thermal expansion coefficient varied from −2.14 to −0.87 × 10−6/°C with increasing Ti4+ content, suggesting a tendency towards zero thermal expansion. In addition, all compositions showed low thermal conductivity, approximately 0.56–0.99 W m−1 °C −1 at 1000 °C. The results indicated that the extraordinary mechanical and thermophysical properties of CaZr4-xTixP6O24 ceramics may have great potential in high-temperature applications.

Ca0.5Sr0.5Zr4P6O24 ceramics added with different amount (0–10 wt%) of ZrP2O7 addition were successfully prepared and characterized, to determine the effects of ZrP2O7 addition on the structure, mechanical and thermal expansion properties of Ca0.5Sr0.5Zr4P6O24 ceramics. X-ray diffraction results show that Ca0.5Sr0.5Zr4P6O24 and ZrP2O7 can coexist in a sintered body without any other phases. The addition of ZrP2O7 can effectively improve the flexural strength and Vickers hardness relative to pure Ca0.5Sr0.5Zr4P6O24 ceramics. Moreover, a low thermal expansion coefficient of 1.3 × 10−6/°C is observed for the ceramics. Considering the low thermal expansion and excellent mechanical properties, Ca0.5Sr0.5Zr4P6O24 ceramics added with ZrP2O7 can be a promising low thermal expansion material.

Ca0.5Sr0.5Zr4-xSnxP6O24 (0 ≤ x ≤ 0.2) ceramics belonging to a new NZP family were prepared by coprecipitation, to determine the effect of Sn4+-substitution for Zr4+ on the crystal structure, mechanical and thermophysical properties of the ceramics. XRD patterns revealed that a single phase was formed for all compositions. Rietveld refinement was used to analyze the crystal structure and the lattice parameters exhibited a satisfactory structural convergence of R-factors. The substitution of Sn4+ for Zr4+ could effectively improve the sinterability, meanwhile, the flexural strength and Vickers hardness could reach to 60.2 MPa and 3.05 GPa, respectively. The thermal expansion varied from 1.72 to 2.78 × 10−6/oC with Sn4+-substitution increasing. Besides, the thermal conductivity of Ca0.5Sr0.5Zr3.8Sn0.2P6O24 (x = 0.2) reached a minimum value of 0.79 W m−1 oC−1 at 1000 °C. The present investigation let provide that the Ca0.5Sr0.5Zr4-xSnxP6O24 ceramics with high mechanical strength and excellent thermophysical properties are promising candidate materials in high temperature applications.

Lower Paleozoic shale is an important source rock and reservoir for gas in the northwestern Upper Yangtze Plate. The paleoenvironment, and its impact on organic matter enrichment of the shale, plays a vital role in the exploration and development of the resource. Based on the analysis of the results of total organic carbon (TOC), maceral examination, bitumen reflectance (Rb), major elements, trace elements, rare earth elements (REEs), and X-ray diffraction (XRD) of shale samples from the Niutitang and Longmaxi formations, the origin of silica, the paleoenvironment, and the mode of organic matter enrichment of the shale were examined. The shales of the Niutitang and Longmaxi formations have high TOC abundance, with Type I organic matter and high maturity. Quartz and clay minerals dominate the mineral constituents, leading to characterization as siliceous shale. The average SiO2 content of the shale in the Niutitang and Longmaxi formations is above 70 wt%. Al2O3 and TFe2O3 (total iron) are the next-most abundant major elements, with average values of 12.80 wt% and 1.95 wt% in the Niutitang Formation, and average values of 11.44 wt% and 4.09 wt% in the Longmaxi Formation. Compared with the Upper Continental Crust (UCC), V, Mo and U are the most enriched elements. The average ∑LREE/∑HREE of the shale samples is very low, and the Chondrite-normalized REE distribution pattern shows sloping LREE trends and flat HREE trends towards the right. The total rare earth elements of the shale vary within the range of 147.85–219.60 ppm and 159.90–222.02 ppm in both the Niutitang and Longmaxi formations, suggesting that the shale has not been subject to obvious hydrothermal fluid activities. The correlation diagrams of SiO2 Al2O3, SiO2-TOC and Siexcess-TOC, the diagrams of hydrothermal origins, and the elemental parameters indicate that the silica of the shales from the Niutitang and Longmaxi formations are mainly of biogenic origins, with a lesser contribution from terrigenous detrital sources. The ratios of MnO2/TiO2 and Al2O3/(Al2O3+TFe2O3) of the shale samples all show limited variability, illustrating that the shales are mainly deposited on the continental margin. The average chemical alteration index (CIA) values of the Niutitang and Longmaxi formations are 71.25 and 72.77 with little variation, and the average Sr/Cu ratios are 4.38 and 2.22, reflecting a warm and humid paleoclimate for both formations. The average Ni/Co, Th/U, and δU readings of the shale samples of the formations are 10.91, 0.97 and 1.51, and 12.69, 0.43 and 1.75, indicating that the redox conditions during the sedimentation of the formations were anoxic. The positive correlations between TOC and paleoenvironmental proxies reveal a warm and humid climate, and that anoxia had a positive effect on organic matter enrichment. These conditions have laid a geological foundation for the enrichment of shale gas, and that the Upper Yangtze Plate is favorable for future shale gas exploration.

It is of significance to elucidate the groundwater quality and hydrogeochemical processes for sustainable utilization of groundwater resources in water shortage regions. A total of 256 groundwater samples were collected in typical watersheds in Zhangjiakou, northern China. The hydrochemical parameters, conventional ions, and trace elements were measured, and δD and δ18O data were collected to delineate the groundwater quality and hydrogeochemical processes. The results showed that 32.91% of the groundwater could be directly used for drinking water sources in the Bashang Plateau, north of the study area. The F− and NO3−-N were the main parameters above the standard threshold for drinking water. In contrast, the groundwater quality in the Baxia River Basins, south of the study area, was of a better scenario. Nonetheless, high concentrations of F−, total hardness, and SO42− were still observed. Most samples in the Bashang Plateau had relatively higher salinity than the Baxia River Basins. Both surface water and groundwater in the study area originated from local meteoric water with considerable hydraulic connections. The high-fluoride groundwater was primarily formed by dissolution of fluoride-rich minerals under conditions of high pH and Na+, low Ca2+, and rich in HCO3−. The dissolution of carbonate and silicate minerals accompanied by strong cation exchange and weak evaporation was the dominant water-rock interaction affecting the hydrochemical composition of groundwater, and anthropogenic NO3− input had an extra influence on hydrochemical process. This study provides a scientific guideline for the protection and allocation of local groundwater resources.

Based on the data of China Geochemical Baselines project, geostatistical analysis was used to investigate the spatial variations in soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents across the “Three Rivers” regions of southwest China, and the factors affecting them were analyzed by the redundancy analysis (RDA) and Person's correlation. Results showed that, the average content of SOC, TN and TP in the study area were 7.20 g/kg, 0.84 g/kg and 0.55 g/kg, respectively. The SOC and TN contents showed an obvious enrichment characteristic with great spatial variability, while TP content was stable on regional scale. The SOC, TN and TP contents decreased with elevation increase in the northern frigid highland, but showed an opposite character in the southern tropical & subtropical, which actually reflected the control of temperature on them. Combined with that there were higher SOC, TN and TP contents in subalpine meadow soil and red earth–yellow earth of the middle latitude zone, these suggested that the suitable temperature was conducive to the accumulation of soil nutrients. The weak positive correlation between population density and soil nutrients, together with high level of soil nutrients in the vicinity of large cities, demonstrated that human activities had significantly increased the soil nutrients contents in the study area. The RDA results showed that soil nutrients in the northern frigid highland were mainly controlled by the environmental factors dominated by temperature and soil structural factors dominated by parent materials with the total explanatory power as high as 75.87%, while in the southern tropical & subtropical mainly by the environmental factors dominated by chemical and biological weathering and the biological factors dominated by vegetation with the total explanatory power as high as 88.53%. The above factors superimposing a certain degree of human activities converged to cause that the SOC and TP contents in the south were higher than that in the north while the TN content was lower than that in the north.

Bimetallic zeolite-imidazole frameworks with controllable flat band position, band gap and hydrogen evolution reaction characteristics were adopted as a photocatalytic hydrogen production catalyst. Furthermore, the g-C3N4–MoS2 2D–2D surface heterostructure was introduced to the ZnM-ZIF to facilitate the separation as well as utilization efficiency of the photo-exited charge carriers in the ZnM-ZIFs. On the other hand, the ZnM-ZIFs not only inhibited the aggregation of the g-C3N4–MoS2 heterostructure, but also improved the separation and transport efficiency of charge carriers in g-C3N4–MoS2. Consequently, the optimal g-C3N4–MoS2–ZnNi-ZIF exhibited an extraordinary photocatalytic hydrogen evolution activity 214.4, 37.5, and 3.7 times larger than that of the pristine g-C3N4, g-C3N4–ZnNi-ZIF and g-C3N4–MoS2, respectively, and exhibited a H2-evolution performance of 77.8 μmol h−1 g−1 under UV-Vis light irradiation coupled with oxidation of H2O into H2O2. This work will furnish a new MOF candidate for photocatalysis and provide insight into better utilization of porous MOF-based heterostructures for hydrogen production from pure water.

The Permian tight clastic reservoir and Ordovician carbonate reservoir were developed in the central-southern Ordos Basin. This study investigated the fluid inclusion petrography, diagenetic fluid characteristics, formation process of natural gas reservoir, source rock characteristics, and reservoir accumulation characteristics of these Paleozoic strata by petrographic observations, scanning electron microscope imaging, fluid inclusion homogenization temperature, salinity, laser Raman spectrum, and gas chromatograph analyses. The results have suggested two phases of fluid inclusions in both the Permian sandstone and the Ordovician Majiagou Formation dolomite reservoirs, and the fluid inclusions recorded the history from the early thermal evolution of hydrocarbon generation to the formation, migration, and accumulation of natural gas. The early-phase inclusions show weak yellow fluorescence and recorded the early formation of liquid hydrocarbons, while the late-phase inclusions are nonfluorescent natural gas inclusions distributed in the late tectonic fractures and recorded the late accumulation of natural gas. The brine systems of the Permian and Ordovician fluid inclusions are, respectively, dominated by CaCl2-H2O and MgCl2-NaCl-H2O. The diagenetic fluids were in the ranges of medium-low temperature and moderate-low salinity. The natural gas hydrocarbon source rocks in the Ordos Basin include both the Permian coal-bearing rocks and the Ordovician carbonates. The process of the early-phase liquid hydrocarbon formation and migration into the reservoir corresponded to 220 Ma (Late Triassic). The late large-scale migration and accumulation of natural gas occurred at 100 Ma (early Late Cretaceous), which was close to the inclusion Rb/Sr isochron age of 89.18 Ma, indicating that the natural gas accumulation was related to the Yanshanian tectonic movement.

Design and synthesis of high-efficiency and low-cost photocatalysts is essential for converting solar energy into clean hydrogen energy. Herein, we report a novel TiO2 nanocrystal photocatalyst confined by ZIF-67-templated porous CoSx, with conductive Ti3C2 boosting the transport efficiency of the charge carriers. TiO2–CoSx and TiO2–Ti3C2–CoSx exhibit a photocatalytic H2-production activity 2.8 and 5.8 times larger than that of pristine TiO2, respectively, because of the existence of the highly porous MOF-templated CoSx hydrogen evolution reaction cocatalyst and highly conductive Ti3C2. This study will provide a practical reference for the design and preparation of efficient photocatalysts with high transport and utilization efficiency of charge carriers.

The design of highly effective noble metal-free cocatalysts plays an extremely important role in improving the photocatalytic solar energy conversion. Herein, we designed and synthesized a novel heterostructure form of MoS2–transition metals (Fe, Co, and Ni) on g-C3N4 nanosheets for obtaining a significant enhancement in the photocatalytic activity for hydrogen production and pollutant disposal. The electrochemical characterization and time-resolved photoluminescence results indicated that the unique tunable feature of the MoS2–transition metals greatly reduced the hydrogen evolution reaction (HER) overpotential, increased the separation, transport and utilization efficiency of the photo-generated charge carriers, and displayed a synergistic effect in improving the electrocatalytic and photocatalytic HER performances. The ternary g-C3N4–MoS2–metals exhibited extremely high photocatalytic HER rates of 1.7, 4.1, and 5.12 mmol h−1 g−1 for g-C3N4–MoS2–Fe, g-C3N4–MoS2–Co and g-C3N4–MoS2–Ni, respectively, which were 2.7, 4.7 and 5.3 times larger than the sum of the photocatalytic HER activities of g-C3N4–MoS2 and the corresponding g-C3N4–metals. This work provides a facile and effective strategy for improving photocatalytic energy conversion using only earth-abundant non-noble cocatalyst heterostructures.

Rationally designing a photocatalytic system is of significance for effectively converting infinite solar energy into clean hydrogen energy. This study revealed that bulk modification of ZnCdS–CdS heterojunction via phosphorus doping and surface modulation by adopting the novel VS2 as the cocatalyst exhibited synergistic effects for improving the photocatalytic activity of the heterojunction. Notably, the photocatalytic hydrogen evolution rate of the pristine ZnCdS–CdS heterostructure raised from 25.46 to 72.82 and 52.82 μmol h−1 using only 5 mg photocatalyst with the bulk and surface modification alone, respectively, while the hydrogen evolution rate increased to 192.28 μmol h−1 with both bulk phosphorus doping and surface adoption of VS2, opening a new method for the improving the photocatalytic activity by both bulk and surface modulation.

The rational design of a photocatalytic cocatalyst is of significant importance for improving the conversion efficiency of solar energy to hydrogen energy. This work indicated that the band structure and hydrogen evolution reaction overpotential of MoS2 cocatalyst derived from phosphomolybic acid (PMo12) could be facilely modulated through phosphorus doping. The PMo12-derived MoS2 could be fabricated at a very low temperature, and exhibited a dramatic enhancement of the photocatalytic hydrogen production activity of CdS. Notably, phosphorus doping over MoS2 could further improve the photocatalytic activity due to the modulated band structure and electrocatalytic performance. Consequently, the photocatalytic hydrogen evolution rate of the pristine CdS could be raised from 0.31 to 4.59 mmol h−1 g−1 by embedding the PMo12-derived MoS2 nanosheet, and further to 8.86 mmol h−1 g−1 after phosphorus doping of MoS2, opening a new method for improving the photocatalytic activity by the rational design of the cocatalyst.

Ca0.5Sr0.5Zr4-xTixP6O24 (x = 0−0.2) ceramics belonging to the NZP family were prepared and dense ceramics with no microcracks were obtained. All of the ceramic samples were still composed of the typical NZP structure with a small amount of Ti4+ substitution for Zr4+. The mechanical and thermal expansion properties of the ceramics were characterized and the result showed that the flexural strength monotonically increased to 66.5 MPa. The thermal expansion coefficient varied from 1.8 to 3.4 × 10−6/°C with Ti4+ content increasing. Thus, it was clear that the substitution of Ti4+ for Zr4+ had obvious effects on the sinterability, mechanical and thermal expansion properties of Ca0.5Sr0.5Zr4-xTixP6O24 ceramics, which were discussed in detail.

Zirconium sol was prepared using precipitation method. In the process, ZrO(OH)2precipitate was firstly obtained through the addition of strong base into the zirconium ions, and then was washed to remove the chloride ion. Lastly, the obtained ZrO(OH)2precipitate was dissolved in nitric acid solution to obtain the white mixed solution. The clear and transparent zirconium sol can be obtained after heated the white mixed solution in a water bath. In this study, the effects of three precipitating agents on the properties of zirconium sol were studied. Zirconium sol prepared by using ammonia as precipitating agent is easy to peptize, while its viscosity is very high. On the other hand, zirconium sol prepared by using urea as precipitating agent exhibits low solid content. Notably, the performance of zirconium sol prepared using ammonia and NH4Cl solution as precipitating agent is best due to its low viscosity and high solid content. In addition, zirconium sol, xerogel and zirconium dioxide powder prepared using ammonia and NH4Cl solution as precipitating agent were systematically characterized by SEM, viscometer, XRD, FTIR. The optimal zirconium sol was synthesized using a peptizing time of 8 h under a peptizing temperature was 80 °C, and the dried amorphous xerogel was converted to tetragonal ZrO2after calcined at 600 °C, while monoclinic at 1000 °C.

Silica ceramics were fabricated via an additive manufacturing process based on stereolithography. Ceramic suspension with low viscosity and high solid loading is of importance to stereolithography based UV-curable. In this work, to meet the requirements of stereolithography, effects of temperature, additive content and ball-milling time on the viscosity of silica slurry were investigated, and properties of silica ceramics sintered at different temperature were also researched.The results show that increasing temperatures strongly decrease the viscosity unless when the temperature is above 70°C. The minimum of viscosity was observed for an appropriate addition of dispersant, which is corresponding to the best dispersion state of silica particles in the photopolymerizable monomer. And optimizing ball-milling time showed the lowest viscosity suitable for the stereolithography process. The appropriate temperature, additive content and ball-milling time facilitating stereolithography was 70°C, 2% and 60min respectively. The prepared ceramics sintered at 1220°C showed a density and flexural strength of 1.57g/cm3 and 13.31MPa respectively.

Low thermal expansion ceramics have been widely applied in multiple fields. In this paper, a series of low thermal expansion ceramics SrZr4-xTix(PO4)6 was prepared and characterized. The SrZr4-xTix(PO4)6 ceramics could be well sintered in the temperature range of 1400~1500 °C. The effect of the addition of Ti substituting Zr and the sintering temperature was studied. The Ceramic with x =0.1 sintered at 1450 °C, the SrZr4-xTix(PO4)6 had a high relative density. The thermal expansion coefficients were about 3.301×10-6 °C-1. It was demonstrated that the microstructure of the SrZr4-xTix(PO4)6 could be altered by adding varying amount of Ti to tailor the thermophysical properties of the material.

In this paper, we added inert filler SiC and ZrC powders in an organic precursor solution to prepare Cf/SiC-ZrC composites. The experiments of three different contents of slurry in the process of impregnation and pyrolysis for Cf/SiC-ZrC composites were studied. The microstructure and composition of Cf/SiC-ZrC composites were analyzed by scanning electron microscope (SEM) equipped with EDS. This study shows that the addition of inorganic powders in an organic precursor solution can shorten the period of preparation of the composite material and improve its strength. When the mass fraction of the inert filler is 15% in an organic precursor solution, the density of the composite material can be increased to 1.9 g·cm-3 rapidly in 8 periods of preparation. Meanwhile, the internal structure of the prepared composite material becomes more compact, and its mechanical properties are excellent.

Ceramics with the formula Ca1-xSrxZr4(PO4)6 (x=0.4, 0.45, 0.5, 0.55) have been synthesized by coprecipitation method, an. their structures, phase transitions, thermal expansion properties have been studied by differential sanning calorimetry, scanning electron microscope, X-ray diffraction and dilatometer. The results show that Ca1-xSrxZr4(PO4)6 ceramics sintered at 1400°C had good sintering condition. Unit cell volume basically had no change with substitution of Ca by Sr. The coprecipitation method saved energy and time. It was introduced to increase the relative density of Ca0.5Sr0.5Zr4(PO4)6 ceramic. The coefficient of thermal expansion was about 1.447×10-6/°C.

A biocompatible nanocomposite consisting of fluorescent quantum dots (QDs) and magnetic nanoparticles (MNPs) has been constructed via carboxymethyl chitosan (CMCS), resulting in magnetic-fluorescent nanoparticles (MFNPs). In these MFNPs, QDs and MNPs are successfully conjugated via covalent bonds onto the surface of CMCS. The composite retains favorable magnetic and fluorescent properties and shows a good colloidal stability in physiological environments. Folate (FA) as a specific targeting ligand was further incorporated into the nanocomposites to form a delivery vehicle with a targeting function. The therapeutic activity was achieved by loading chemotherapeutic drug doxorubicin (DOX) through electrostatic and hydrophobic interactions. The cumulative DOX release profile shows pH-sensitive. Both flow cytometry analysis and confocal laser scanning microscopic observation suggested that these nanocomposites were uptaken by cancer cells via FA receptor-mediated endocytosis pathway. In summary, the CMCS based nanocomposites developed in this work have a great potential for effective cancer-targeting and drug delivery, as well as in situ cellular imaging.

A visible light-driven cadmium-free ZnS/rGO/CuS porous photocatalyst heterojunction was synthesized by simple hydrothermal and cation exchange methods using a zeolitic imidazolate framework (ZIF-8) as the template and Zn precursor. Due to the ZIF-8 templated high porous microstructure and/or the high carrier conductivity of the graphene (rGO), ZnS/CuS and ZnS/rGO/CuS heterojunctions exhibited a photocatalytic H2-production activity 9 and 13 times larger than that of the counterpoint heterojunction derived from the inorganic precursors under visible light irradiation, respectively. This work will provide an insight into the design and synthesis of ternary composite photocatalyts with high porosity and efficient charge separation and transfer.