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The meandering channel deposit of the upper member of Neogene Guantao Formation in Shengli Chengdao extra-shallow sea oilfield is characterized by rapid change in sedimentary facies. In addition, affected by surface tides and sea water reverberation, the double sensor seismic data processed by conventional methods has low signal-to-noise ratio and low resolution, and thus cannot meet the needs of seismic description and oil-bearing fluid identification of thin reservoirs less than 10 meters thick in this area. The two-step high resolution frequency bandwidth expanding processing technology was used to improve the signal-to-noise ratio and resolution of the seismic data, as a result, the dominant frequency of the seismic data was enhanced from 30 Hz to 50 Hz, and the sand body thickness resolution was enhanced from 10 m to 6 m. On the basis of fine layer control by seismic data, three types of seismic facies models, floodplain, natural levee and point bar, were defined, and the intelligent horizon-facies controlled recognition technology was worked out, which had a prediction error of reservoir thickness of less than 1.5 m. Clearly, the description accuracy of meandering channel sand bodies has been improved. The probability semi-quantitative oiliness identification method of fluid by prestack multi-parameters has been worked out by integrating Poisson's ratio, fluid factor, product of Lame parameter and density, and other prestack elastic parameters, and the method has a coincidence rate of fluid identification of more than 90%, providing solid technical support for the exploration and development of thin reservoirs in Shengli Chengdao extra-shallow sea oilfield, which is expected to provide reference for the exploration and development of similar oilfields in China.

It is a great challenge to enhance the specific capacitance while without sacrificing the remarkable rate capability and long-term cycle durability of carbon materials for supercapacitors. Here we present a novel spherical and multi-shell hollow carbon material with tunable shell numbers and N-doping derived from a sequential synthetic route recombining hydrothermal nucleation, carbonization, and etching. The very special features, including uniform in shape and size, hollow structure, core/multi-shell architecture, hierarchical porous structures, and nitrogen doping, facilitated high specific surface area, abundant active sites, fast ion diffusions kinetics and good electrical conductivity. As a result, very superior electrochemical performance with an excellent combination of high specific capacitance (318.5 F g−1), and outstanding rate capability (the capacity retention ratio was more than 80% when the current density was raised from 0.1 to 10 A g−1), and very stable cycling (more than 94% capacity retention after 50000 cycles at 1 A g−1) has been achieved. This hierarchical multi-shell strategy opens a new avenue for design of high performance electrode for next-generation energy storage devices.

In this study, a new type of polyimide (PI) composite material was synthesized by a two-step method using 2,3,5,6-tetramethyl-1,4-phenylenediamine (TMPDA), 4,4′-methylenedianiline (MDA), and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA). The PI material was then used to prepare an ultrafiltration (UF) membrane by phase inversion method. The membrane showed a dense surface layer, a porous sublayer, and fully developed finger-like macrovoids at the bottom, which had excellent hydrophilicity and antifouling property. In the recovery experiments with a protein solution, the PI membrane displayed a satisfactory water flux recovery ratio of 90.03%. The PI membrane can operate stably in 1 mol L−1 hydrochloric acid solution, and the retention rate of BSA remains at 93%. In addition, the flux of the membrane is 325.60 L m−2 h−1 and the BSA retention rate the retention rate is still higher than 95% after soaking in various solvents for 7 days.

This work focused on a fabrication of lotus root-like Li3V2(PO4)3/C composites via a repeated immersion process using the dandelion as a bio-template. The Li3V2(PO4)3/C composites were characterized using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The Li3V2(PO4)3/C composites exhibited various structures that were dependent on the various processing techniques. By increasing immersion of the product to three repetitions, a bundle of dandelion carbon fibers was found to be covered by Li3V2(PO4)3 and formed a perfect lotus root-like structure (D-3). The Li3V2(PO4)3/C composite (D-V) prepared using the vacuum method displayed a dense scrub board-like structure. However, sample D-3 that was prepared using the novel method, exhibited a capacity of 126.8 mAh g−1 at the 1 C rate, a prominent capacity retention of 96.8% after 2000 cycles at the 15 C rate. The experimental results showed that this unique lotus root-like structure is beneficial for improving the capability and cycling stability.

Carbon materials as host matrix of lithium (Li) anode attract more and more attention in order to inhibit uncontrollable dendritic growth of Li. Powdery carbon materials are usually synthesized and loaded on current collector by binder. The pore structure and active site of powdery materials will be easily destroyed during cycling. Herein, a self-supporting carbon film consisting of nitrogen (N)-doped carbon rod array (NCRA) with high N content and large surface area skeleton is developed as Li host matrix to regulate Li metal nucleation and suppress dendrites growth. The NCRA matrix exhibits low lithium loss mass and good long-term cycling stability during Li plating/stripping. The loss mass of Li in each cycle on NCRA is less than 0.01 mg cm−2 at 1.0 mA cm−2 and the value is much smaller than that (0.063 mg cm−2) on Cu foil. The Li|NCRA@Li symmetric cell has ultralong lifespan beyond 620 h and small voltage hysteresis of less than 40 mV at 2.0 mA cm−2. The good electrochemical performance is ascribed to the stable self-supporting array structure for the storage of Li and abundant lithiophilic active sites for uniform Li electrodeposition in NCRA host matrix. Therefore, the dendritic growth of Li is effectively inhibited. This study provides a promising self-supporting lithiophilic NCRA as host material of Li anode to promote practical application in next-generation lithium-metal based batteries.

This is the first report of the use of an original precursor obtained from an abundant, green and economical bio-mass waste: cattail fibers. Nitrogen-doped Li3V2(PO4)3/carbon composites with copious conductive networks have been successfully synthesized using cattail fibers as a bio-template employing facile, repeated solution immersions. The morphologies and microstructure of the nitrogen-doped Li3V2(PO4)3/carbon composites were characterized using an X-ray diffractometer and scanning electron microscopy. A nitrogen-doped Li3V2(PO4)3/carbon composite (sample C-3) was obtained through three times solution immersion, which completely covered the carbon fibers with thin, porous layers of Li3V2(PO4)3. These orderly nitrogen-doped Li3V2(PO4)3/carbon (C-3) were orderly interconnected porous Li3V2(PO4)3 nanoconnections. This novel structure was found to have interlaced conductive networks that were formed between the N-doped carbon fibers and porous Li3V2(PO4)3 nanoconnections. However, the Li3V2(PO4)3/carbon composites, termed sample (C-V), obtained using the immersion process in a vacuum, displayed a random accumulation of rod-like Li3V2(PO4)3/carbon composites. Sample C-3 exhibited the highest reversible capacity of 113.2 mAh g−1 after 500 cycles at 15 C between 3.0 and 4.3 V, but at under these same conditions, the remaining reversible capacity of sample C-V was only 82.3 mAh g−1.

This work focused on the design and fabrication of porous, nitrogen-doped Li3V2(PO4)3/C cathode materials using a repeated impregnation synthesis process employing oroxylum as a template. The resulting Li3V2(PO4)3/C cathode materials were comprehensively analyzed using Fourier transform infrared spectroscopy, X-ray diffraction analysis, selected area electron diffraction, scanning electron microscopy and galvanostatic experiments. The Li3V2(PO4)3/C cathode materials of varying structure were prepared by various processing techniques using select precursors. The resulting porous, nitrogen-doped Li3V2(PO4)3/C cathode materials (IM-15) obtained using repeated impregnation exhibited a novel, overlapping hollow slab structure, which was covered by thin layers of porous, foamed Li3V2(PO4)3 on the surface of IM-15. It was found that the porous, foamed Li3V2(PO4)3 material was sandwiched between thin layers of adjacent Li3V2(PO4)3/C layers. IM-15 product exhibited an outstanding rate capability of 87.4 mAh g−1 at the 10 C rate, and an excellent capacity retention of 96.9% after 1000 cycles at 5 C in the range of 3–4.3 V. These results were attributed to the porous, nitrogen-doped structure of the material, which provided a high diffusion coefficient and superior structural stability. The unique porous, nitrogen-doped structure was responsible for improving the rate capability and cycling stability of LIBs containing the subject experimental material.

Folded-hand silicon/carbon (Si/C) three-dimensional (3D) networks were fabricated by chemical vapor deposition coupled with ultrasonic atomization and successfully applied for a binder-free anode in lithium-ion batteries. The microstructure, morphology and electrochemical performance for Si/C 3D networks were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and galvanostatic charge-discharge tests. The repeated folded-hand units for Si/C composites are assembled into interconnected 3D networks. The folded-hand Si/C 3D networks show an outstanding charge capacity of 2277 mAh g−1 at 0.1 C, and still remain 2167 mAh g−1 after 100 cycles. They reveal an excellent rate capacity of 1848 mAh g−1 and capacity retention of 99% after 100 cycles at 2 C, the charge capacities of 862 mAh g−1 and capacity retention of 93% after 500 cycles at 5 C. The LiFePO4//Si-C full cell can maintain high capacity of 137 mAh g−1 and capacity retention of 92% after 500 cycles at 1 C rate. The superior electrochemical performance is attributed to the formation of three-dimensional folded-hand interconnected networks.

A novel, sulfur host, Mn3O4-CNTs microsphere was prepared by ultrasonic spraying with subsequent impregnation methods and appeared to effectively mitigate the dissolution of intermediate polysulfides from the Li-S cathode. Mn3O4-CNTs microspheres are caddice-like balls that are interwoven with CNTs that contains Mn3O4 nanoparticles. These novel Mn3O4-CNTs microspheres were found to exhibit high initial charge and discharge capacities of 1216 and 1227 mAh g−1 at 0.1 C and they exhibited a favorable cycle stability of 1087 mAh g−1 at 0.2 C after 200 cycles. These attributes make this new material a good, potential cathode material for lithium-sulfur batteries.

The Li3V2(PO4)3/C composite with hollow coaxial structure has been successfully synthesized via a facile repeated immersion method induced by cotton fibers. The morphologies, structures and properties are investigated by X-ray diffractometer, scanning electron microscopy and galvanostatic charge-discharge tests. Li3V2(PO4)3/C composite displays a unique hollow coaxial structure constructed by hollow carbon fibers filled with Li3V2(PO4)3/C particles inside and coated by Li3V2(PO4)3/C layer outside. Li3V2(PO4)3/C composite exhibits good rate performance with a specific capacity of 115.7 mAh g−1 at 15 C rate between 3.0 and 4.3 V. The improved properties can be attributed to the formation for hollow coaxial structure.

Sb2O3 with symmetric bundle-shaped architecture has been successfully prepared and applied for anode materials in lithium ion batteries. The microstructures and electrochemical performances were investigated by XRD, SEM and TEM measurements and galvanostatic charge–discharge tests. The bundle-shaped Sb2O3 is in an average length of approximately 20 μm and its end exhibits a bouquet-like structure. Sb2O3 shows a good reversible capacity of 594.1 mAh g−1 at 20 mA g−1, rate capability of 232.6 mAh g−1 at 200 mA g−1. The excellent properties of the bundle-shaped Sb2O3 have become a candidate anode material for lithium-ion batteries.

Liquid leakage and lithium dendrite growth are common safety hazards of lithium-ion batteries, and the application of quasi-solid electrolytes are considered to be the most promising material for inhibiting the safety problems. Herein, a new type of bi-functional ionic liquid is synthesized and polymerized into double cross-linked poly(ionic liquid) electrolyte (denoted as PIL-PEI) by dual cross-linking method [ring-opening polymerization network: epoxy groups in 1-vinyl-3-epoxypropylimidazolium bis(trifluoromethanesulfonyl)imide (VEIM-TFSI) cross-linked with amino-groups in poly(ethylene imine) (PEI), radical cross-linking network: VEIM-TFSI cross-linked with poly(ethylene glycol) diacrylate (PEGDA)]. The Double cross-linked network of PIL-PEI reveals satisfactory flexibility, thermal stability and remarkable electrochemical performances (room-temperature ionic conductivity, 1.03 × 10−3 S cm−1 and lithium-ion transference number, 0.47). Furthermore, the compact network of PIL-PEI enables the formation of a strong solid electrolyte interface (SEI) layer on the lithium metal leading to the inhibition of lithium dendrite growth. As results, the batteries electrochemical performances, such as high charge/discharge capacity (165.6 mAh g−1), robust rate behavior (5.0C for 94 mAh g−1) and long-term lifespan (97.8% coulomb efficiency after 200 cycles) are significantly improved after assembled by LiFePO4-based cells equipping PIL-PEI as electrolyte. The soft package cell assembled with PIL-PEI is able to successfully light up the LED light and keep illuminating under varying hazardous situations such as bending and cutting, indicating that the PIL-PEI will have potential application value in highly secure flexible electronic devices.

Battery-type electrode materials have recently been considered as a new class of high-capacity cathode materials for construction of hybrid supercapacitors, however, their low electrochemical kinetics prevent the practical application. Here, the NiCo2S4/nitrogen and sulfur dual-doped three-dimensional (3D) holey-reduced graphene oxide (NiCo2S4/N, S-HRGO) composite architectures were synthesized via a two-step hydrothermal approach. Thanks to the introduction of 3D interconnected and highly conductive holey-reduced graphene oxide with mesopore-rich structure providing fast electron/ion transport, the as-resulted NiCo2S4/N, S-HRGO composite achieves enhanced supercapacitive performances, especially exceptional rate capability compared to the pure NiCo2S4 and NiCo2S4/nitrogen and sulfur dual-doped reduced graphene oxide (NiCo2S4/N, S-RGO). The NiCo2S4/N, S-HRGO composite shows a specific capacity of 184.2 mAh g−1 at 1 A g−1, and still maintains a high specific capacity of 119.5 mAh g−1 even at 50 A g−1. The excellent rate capability of the composite can be illustrated by in-depth kinetic analysis based on the calculated diffusion coefficient and charge contribution ratio. Furthermore, a hybrid supercapacitor utilizing NiCo2S4/N, S-HRGO and N, S, P tri-doped holey-reduced graphene oxide (N, S, P-HHGO) respectively as the cathode and anode is further constructed, showing a satisfactory energy density (35.4 Wh kg−1), high power density (15.0 kW kg−1) and good cycle durability.

In this work, three different morphologies of CuCo2S4 materials have been prepared by a facile hydrothermal synthesis route by controlling the species of solvent and molar concentration of precursors. The effects of reaction conditions on the physical characteristics (including microstructure, morphology, specific surface area and pore structure) and electrochemical behaviors of the products were systematically investigated. The experimental results reveal that as-obtained highly uniform micro-/nanostructure CuCo2S4 particles prepared by mixed solvent (H2O/ethylene glycol(EG)) and low molar concentration of precursors manifest the best electrochemical performances. The specific capacity is up to 90.6 mAh g−1 at a current density of 2 A g−1, and 47.9% of capacity retention rate can be retained when the current density varies from 2 to 50 A g−1. Furthermore, a superior cycling stability with 95.6% of initial capacity retention rate can be maintained at 3 A g−1 after 5000 consecutive charge-discharge cycles. The enhanced electrochemical performances can be mainly attributed to the highly uniform micro-/nanostructure with relatively larger specific surface area and total pore volume. Therefore, the results above demonstrate that the as-prepared highly uniform micro-/nanostructure CuCo2S4 particles might be promising candidate battery electrode materials for energy storage.

Uniform nanocable-like Nb2O5/surface-modified carbon nanotubes (SMCNTs) composites for anode materials in lithium ion batteries were synthesized by hydrothermal method. It was indicated that Nb2O5 nanoparticles were tightly and uniformly cultivated on carbon nanotubes when CNTs were pretreated with concentrated H2SO4. As a result, Nb2O5/SMCNTs composite materials showed remarkable electrochemical performance as anode materials for lithium-ion batteries. It delivered a high reversible capacity of 441 mA h g−1 cycled at the current density of 40 mA g−1 after 100 cycles and an excellent rate capacity of 185 mA h g−1 at the high current density of 5000 mA g−1 after 200 cycles.

Uniform Nb 2 O 5 nanospheres/surface-modified graphene (SMG) composites for anode materials in lithium ion batteries were synthesized by hydrothermal method. The microstructure and morphology of composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscope techniques. The experimental results showed that Nb 2 O 5 nanospheres were tightly and uniformly grown on the surface of SMG nanosheets. Nb 2 O 5 nanospheres/SMG composites exhibited an impressive reversible capacity of 404.6 mA h g −1 at the current density of 40 mA g −1 after 100 cycles, and an excellent rate capacity of 345.5 mA h g −1 at the current density of 400 mA g −1 .

Membrane separation processes constitute an economical and efficient technology for the effective treatment of dye wastewater. In this study, 4,4′-diaminodiphenylmethane and 1,3,5-benzenetricarbonyl trichloride were used as monomers to prepare polyamide-based nanofiltration (NF) membranes by interfacial polymerization, for dye removal. The preparation parameters of the NF membrane were optimized by investigating the effects of the concentrations of two monomers, the soaking time of the carrier in aqueous solution of monomer, and the polymerization time on the membrane performance. The surface roughness of optimized membrane was found to be only 5.08 nm, and the stabilized contact angle was about 25°, indicating very high hydrophilicity. When the pH was in the range from 3 to 10, the membrane surface became electronegative, which resulted in a high rejection rate toward various negatively charged dyes. For the congo red dye solution, the membrane showed a flux of 36.81 L m−2 h−1 and a rejection rate of 99%. The rejection rate of the other two negatively charged dyes investigated herein was also above 95%. Moreover, the filtration experiment of bovine serum albumin solution showed that the flux recovery rate of the membrane was up to 89.85%, indicating good stability and antifouling performance.

The design and development of bowl-like hollow carbon submicrospheres (BHCSs) with hierarchical porous structure as a new class of hollow carbon structure has recently attracted increasing attention. Herein, the coarse bowl-like hollow carbon submicrospheres (CBHCSs), smooth bowl-like hollow carbon submicrospheres (SBHCSs) with hierarchical mesopore-rich structure and their hollow carbon submicrospheres (HCSs) counterparts were prepared through a facile sequential heterogeneous nucleation route by changing the temperature and the molar concentration of reactants. The electrochemical measurements reveal that the CBHCS electrode displays a high specific capacitance of 294 F g−1 at 1 A g−1 because of the large specific surface area and superior cycling performance with 89.58% of its initial capacitance over 10,000 cycles due to its hierarchical mesopore-rich structure, while the SBHCS electrode shows the best rate capability with 55% of capacity retention at 20 A g−1 resulted from their thinner shell of hollow carbon submicrospheres. Obviously, the differences of electrochemical performances can be mainly ascribed to the morphology, specific surface area, hierarchical porous structure and hollow shell thickness of these as-prepared samples. The superior capacitive behaviors coupled with the facile and low-cost preparation approach render BHCSs as highly prospective electrode materials for application in supercapacitors or other energy storage systems.

Advanced information and communication technologies and social media (Web 2.0) have significantly shaped every aspect of contemporary society since Kent and Taylor’s (1998) proposal of dialogic principles, which later evolved into dialogic theory of public relations. It is now time to move the theory forward. The special section aims to advance the dialogic theory of public relations by reviewing the scholarship in organization-public dialogue to pinpoint critical issues for its development and introducing studies that take the dialogue approach to examine a range of public relations practices in China. In this introduction, we first identify critical issues to be addressed for the development of the dialogic theory of public relations and then introduce the articles included in the section. We conclude by proposing research directions for the theoretical and practical development of the dialogic approach to public relations.

After thirty years of development in mainland China, public relations is suffering from a stigma because of its negative connotations, misconception and paradoxical perception among the general public, and development constraints. To overcome this stigmatization, a positive public relations theory that posits the positive functions of public relations in contemporary China is proposed by integrating the three public relations dimensions (i.e., communication, organization-public relationships, and ecological networks), the dialogic theory of public relations and the Chinese philosophical thinking of Yin and Yang. To achieve this, the paper first explains the cause of stigmatization in public relations. Second, it introduces the three dimensions of public relations as a profession and discipline. It then articulates how the dialogic theory of public relations and the Yin Yang philosophy contribute to the development of positive public relations. Lastly, it proposes the Taiji model of public relations and the underpinnings of positive public relations. It is important to note that positive public relations serves as a complement to, rather than a substitute for, existing theories of public relations.

It is worthy of attention that the honeycombed Li3V2(PO4)3/C composites have been prepared and used as the cathode materials for lithium-ion batteries. The honeycombed Li3V2(PO4)3/C composites were synthesized via vacuum-assisted immersion method using the dandelion fibers as the biomass-carbon templates. The composites were characterized using X-ray diffraction, transmission electron microscopy and scanning electron microscopy. The honeycombed Li3V2(PO4)3/C composites exhibit a capacity of 123.40 mA h g−1 and a prominent capacity retention of 98.78% at the 0.2 C rate, while the rate capacity retention is as high as 88.84% at 15 C rates. It is demonstrated that the unique honeycombed structure is beneficial for improving structural stability and Li+ diffusion coefficient of the lithium ion batteries, and then enhance the high-rates and cycle performance.

The practical applications for Li–S batteries rely on the restriction of shuttle effect from polysulfides and the improvement of conductivity of sulfur and Li2S. 3D hierarchical nitrogen-doped graphene/carbon nanotubes (N-GCNTs) microspheres were prepared by one-step ultrasonic spraying deposition method. N-GCNTs microspheres are consisted of sucrose, graphene and water-soluble carbon nanotubes and are named according to different mass ratio, like N-GCNTs-1 (1:1:1), N-GCNTs-2 (1:3:1) and N-GCNTs-3 (1:5:1). N-GCNTs-2 microspheres have 3D porous structure with abundant of N atoms which is constituted by the intertwine of nanotubes and graphene, and maintained the characteristics of 1D and 2D nano-carbon. By contrast, N-GCNTs-1 microspheres shows broken microspheres connected by a few CNTs, and N-GCNTs-3 microspheres expose the smoother and integrated spheres which are hardly found CNTs. N-GCNTs-2 microspheres mainly manifest the eminent physical characterization for big BET specific surface area (575.8 m2g-1) and pore volumes (0.303568 cm3g-1) and high sulfur content (87.5%). Moreover, N-GCNTs-2 microspheres show the high initial discharge capacities of 1465.1 mAh g−1 at 0.1 C, good cycle stability of 1315.1 mAh g−1 after 200 cycles and outstanding long-term cycling performance of 849.1 mAh g−1 after 500 cycles at 2.0 C. The N-GCNTs-2 microspheres effectively enhance the electrochemical performance of cathodes for lithium-sulfur batteries due to 3D hierarchical porous structure and successful N-doping.

Heteroatom doped graphene-based materials have been illustrated to be a superior approach to improve the performance of electrode materials for supercapacitors. In this work, the graphene oxide (GO) was prepared by a modified Hummers’ method employing expanded graphite as precursor, and further etched by hydrothermal method to obtain holey graphene oxide (denoted as HHGO). The resulting HHGO was utilized to synthesize a novel nitrogen(N), sulfur(S) and phosphorus (P) tri-doped holey GO (N, S, P-HHGO) material by a hydrothermal approach utilizing ammonium dihydrogen phosphate and L-cysteine as N, S and P sources and used as supercapacitor electrode materials for the first time. The electrochemical results reveal that the N, S, P-HHGO delivers a high gravimetric capacitance of 295 F g−1 at 1 A g−1 in 2 M KOH aqueous electrolyte, outstanding rate capability with 71.2% of capacity retention rate from 1 to 20 A g−1 and excellent cycling stability with 93.5% of initial capacity retention at 3 A g−1 above 10000 cycles. The outstanding electrochemical properties of N, S, P-HHGO can be attributed to a superior pore-size distribution and the introduction of N, S and P heteroatoms, and shows great potential application in supercapacitors as well as other energy storage devices.

This study re-conceptualizes the interaction between public relations (PR) practitioners and journalists in news construction. Proposing a new conceptual framework of “news-source involvement,” this study applies two dimensions – “involvement width” and “involvement density” – when examining how information and/or stories generated by PR people affect news coverage. Empirically, this study identifies seven types of news sources derived from a systematic content analysis of 1600 stories in four selected Chinese newspapers from 2001 to 2010 – 10-year period. The major findings include: (1) information subsidy has become a popular phenomenon in China; (2) over the past decade, the Chinese government has been slowly but surely becoming more tolerant of public's expression of their opinions relating to social and political issues. Though the government remains as the dominating “news source” for newspapers, other non-mainstream news sources (e.g. grass-root civilian) have emerged. Growing from the used-to-be “silent mass,” they have become the “subordinate majority” nowadays, having strong influence in certain coverage; and (3) PR people as one of the major news sources, interact with media in a selective manner; and such interaction takes places largely on tactical level.

A novel liquid crystal functionalized multi-walled carbon nanotubes (LC-MWNTs)/2-methyl-N,N′-bis(4′-methoxy benzoyloxy)-terephthalamide liquid crystal (LC) nanocomposite (LC-MWNTs/LC) was prepared via solution blend. The dispersion and thermal property of the nanocomposites with different loadings of LC-MWNTs (0.1–1 wt.%) were investigated using SEM, TGA and DSC. The results show that the dispersion of LC-MWNTs in LC matrix is more homogeneous than purified MWNTs. The decomposition temperature of nanocomposites exhibits obvious decrease at first and then increase with increasing concentration of LC-MWNTs, which is lower than that of LC for 0.1–0.4 wt.% LC-MWNT loadings and higher than that of LC for 0.5–1 wt.% LC-MWNT loadings. The addition of LC-MWNTs has little effects on the texture of smectic mesophase. These results illustrate the LC-MWNTs/LC nanocomposites, which have lower melting point and higher decomposition temperature than those of LC by adding adequate amount of LC-MWNTs, show a wide temperature range of mesophase and high thermostability. The increased mesophase temperature region of LC materials will be beneficial to their practical applications.

A non-silicate material, yttrium phosphate (YPO 4 ), is developed for the application as environmental barrier coatings. The key issues of environmental durability, phase stability, chemical compatibility, and coefficient of thermal expansion (CTE) are considered for the selection of YPO 4 . The water corrosion behaviors for the sol–gel prepared YPO 4 were investigated in an atmosphere of 50% H 2 O–50% O 2 water vapor at 1350 °C. The hot corrosion study of YPO 4 was carried out at 900 °C with Na 2 SO 4 melt. The results demonstrate that YPO 4 has excellent environmental durability. During these tests, YPO 4 had no phase change and decomposition. Moreover, the reactions between YPO 4 and silica at high temperatures were not detected, indicating the good chemical compatibility of YPO 4 . The measured CTE of YPO 4 is close to that of SiC. The suitable CTE, good environmental durability and chemical compatibility, and excellent phase stability of YPO 4 indicate that it is a potential environmental barrier coating material.

Multiwalled carbon nanotubes (MWCNTs) were modified via polymerization of styrene under microwave irradiation, and polystyrene (PS)–MWCNT composites with individual-dispersed nanotubes were prepared by melt-mixing using industrial extruder and injection moulding machine. The microscopic morphologies of modified MWCNTs (m-MWCNTs) and composites were studied through transmission electronic microscopy and scanning electron microscopy. Result showed that a PS coat layer was introduced on the m-MWCNT surfaces, improving the compatibility of nanotubes with poor polar materials such as tetrahydrofuran, toluene, and PS matrix. Contrary to the composite prepared directly using purified MWCNTs (PS–p-MWCNT composite) without further modification, the composite prepared using m-MWCNTs (PS–m-MWCNT composite) exhibited a PS middle layer between nanotubes and matrix, leading to a strong interfacial adhesion. Thereby, although the nanotubes are individually dispersed in both PS–p-MWCNT and PS–m-MWCNT composites, the mechanical property of the latter is better than that of the former. When the nanotube content is 0.32 wt%, the PS–m-MWCNT composite had a 250% increase of impact strength as compared to pure PS, but the PS–p-MWCNT composite had only a 150% increase. Furthermore, the tensile strength of PS–p-MWCNT composite descended slightly with the addition of nanotube content, whereas, that of the PS–m-MWCNT composite ascended slightly.

Effective functionalization of multi-walled carbon nanotubes (MWCNTs) with styryl group was carried out via the esterification reaction of the carboxylate salt of carbon nanotubes and 4-vinylbenzyl chlorides in toluene. The functionalized MWCNTs were characterized through FTIR and Raman spectra to confirm the styryl groups covalently connected to the surface of MWCNTs. The weight loss of functionalized moieties determined by thermogravimetry-differential scanning calorimertry analysis is around 36%. Nanotube-reinforced polystyrene were fabricated by mixing functionalized MWCNTs and polystyrene. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images showed that the functionalized nanotubes had a better dispersion than the unfunctionalized MWCNTs in the matrix. Moreover, styryl-modified MWCNTs/PS nanocompsite presented obvious improvements in mechanical properties and thermal stability.

The functionalized multi-walled carbon nanotubes (MWNTs) with amino groups were prepared after such steps as oxidation, the addition of carboxyalkyl radicals, acylation and amidation. Besides oxidated-MWNTs/epoxy nanocomposites, amino-functionalized MWNTs/epoxy nanocomposites, in which MWNTs with amino groups acted as a curing agent and covalently attached into the epoxy matrix, were fabricated. Subsequently, the effects of MWNT content on the mechanical and thermal properties for the two systems were investigated. It is found that both the tensile strength and impact strength enhance with the increase of MWNT addition, and the most significant improvement of the tensile strength (+51%) and especially impact strength (+93%) is obtained with amine-treated MWNTs at an 1.5 wt.% content. Moreover, the thermal stability of the nanocomposites also distinctly improves. The improvement of the properties of the amine-treated MWNTs system is more remarkable than those of o-MWNTs system. The reasons for these changes were discussed.

An easy method for purifying multi-walled carbon nanotubes (MWCNTs), involving chlorine water and ammonia water treatments, is described. Transmission electron microscopy, X-ray diffraction, energy dispersive X-ray analysis and Fourier-transform infrared spectroscopy were used to characterize the purified MWCNTs. It was shown that catalyst particles, amorphous carbon, and carbon particles were almost completely eliminated after purification and the tips of the purified MWCNTs were opened. During purification, the crystal structure of the MWCNTs was unchanged and some carboxyl groups and C-Cl bonds were introduced. Sedimentation experiments showed that the purified MWCNTs could be easily dispersed in polar solvents such as water, ethanol, acetone, chloroform and N,N-dimethylformamide.