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During the first 30 years of the twentieth century, Vietnamese literature began to enter the period of restructuring in the direction of modernization. This process occurred in the conflicting existence between two tendencies: the former educated class tried to preserve the traditional values of the classical literature whereas the younger scholars actively absorbed the modern Western literature and gradually moved towards the new literature. Faced with the challenges and opportunities of the time, a Confucian like Tan Da boldly removed the “olds” in the pursuit of the “news”, integrating the Western thoughts into the Eastern wisdom to crystallize a unique and brand new form of literature. His works embraced the depth brought by the Oriental culture and adopted more colors with the Western breaths. Within this modernization process, his efforts to approach modern novels and his tendency to liberalize poetry are two among the most important contributions of Tan Da, opening up possibilities for the next generation of writers as well as helping accelerate modernization in national literature.

It can be said that the sustainable relationship with traditional culture was one of the most stable and profound value systems in Tan Da literature. Tan Da lived in a transitional period which contained fluctuations and conflicts between the old and the new, between tradition and modernity. However, Tan Da still retained his lofty principles so that he could dedicate himself to life passionately, could fulfill the dream of practicing the morality and could preserve the beauty of someone who always remained loyal to Confucianism.

The present study aims to investigate adsorption characteristics and mechanisms of Moringa (MO) seeds protein on nanosilica rice husk and their applications in removal of pharmaceutical residues including the fluoroquinolone antibiotic levofloxacin (LFX) and the nonsteroidal anti-inflammatory drug diclofenac (DCF) in aquatic environment. Molecular weight of MO protein was determined by gel-permeation chromatography (GPC) method while its amino acids were quantified by high performance liquid chromatography (HPLC). The number-(M

Co-digestion of organic waste and wastewater is receiving increased attention as a plausible waste management approach toward energy recovery. However, traditional anaerobic processes for co-digestion are particularly susceptible to severe organic loading rates (OLRs) under long-term treatment. To enhance technological feasi-bility, this work presented a two-stage Anaerobic Membrane Bioreactor (2 S-AnMBR) composed of a hydrolysis reactor (HR) followed by an anaerobic membrane bioreactor (AnMBR) for long-term co-digestion of food waste and kitchen wastewater. The OLRs were expanded from 4.5, 5.6, and 6.9 kg COD m- 3 d-1 to optimize biogas yield, nitrogen recovery, and membrane fouling at ambient temperatures of 25-32 degrees C. Results showed that specific methane production of UASB was 249 +/- 7 L CH4 kg-1 CODremoved at the OLR of 6.9 kg TCOD m- 3 d-1. Total Chemical Oxygen Demand (TCOD) loss by hydrolysis was 21.6% of the input TCOD load at the hydraulic retention time (HRT) of 2 days. However, low total volatile fatty acid concentrations were found in the AnMBR, indicating that a sufficiently high hydrolysis efficiency could be accomplished with a short HRT. Furthermore, using AnMBR structure consisting of an Upflow Anaerobic Sludge Blanket Reactor (UASB) followed by a side -stream ultrafiltration membrane alleviated cake membrane fouling. The wasted digestate from the AnMBR comprised 42-47% Total Kjeldahl Nitrogen (TKN) and 57-68% total phosphorous loading, making it suitable for use in soil amendments or fertilizers. Finally, the predominance of fine particles (D10 = 0.8 mu m) in the ultra -filtration membrane housing (UFMH) could lead to a faster increase in trans-membrane pressure during the filtration process.

The azo dyes new coccine (NCC) were successfully removed through the adsorption onto PVBTAC-modified α-Al2O3 particles. The optimal conditions of both the surface modification by PVBTAC adsorption and the NCC adsorption were thoroughly investigated. Formerly, polycations PVBTAC were adsorbed onto the nanosized α-Al2O3 particles atpH8, NaCl 100 mM, with a contact time of 2 h, and initial concentration of 1000 ppm to modify the α-Al2O3 surface. Latterly, the NCC adsorptive removal was conducted atpH8, NaCl 10 mM, α-Al2O3 adsorbent dosage of 3 mg mL−1, and a contact time of 45 min. Interestingly, the optimalpHof 8 potentially applies to treat real wastewater as the environmentalpHrange is often about 7–8. High removal efficiency and adsorption capacity of the NCC azo dyes were, respectively, found to be approximately 95% and 3.17 mg g−1 with an initial NCC concentration of 10 ppm. The NCC adsorption on the modified α-Al2O3 particles was well fitted with a Freundlich model isotherm. A pseudo-second kinetic was more suitable for the NCC adsorption on the PVBTAC-modified α-Al2O3 surface than a pseudo-first kinetic. The NCC adsorptive removal kinetic was also affirmed by the FT-IR spectra, based especially on the changes of functional group stretch vibrations of −SO3− group in the NCC molecules and −N+(CH3)3 group in the PVBTAC molecules. The high reusability of the α-Al2O3 particles was proved to be higher than 50% after four generation times.

Crystalline ultrathin TiO2 nanowires with oriented configurations are promising for high-performance energy storage and conversion devices. In this work, we use hierarchical microspheres constructed from radially oriented single-crystalline TiO2 nanowires as electrode materials for reversible Mg-ion intercalation. The obtained mesoporous TiO2 nanowires deliver a capacity of 118 mA h g−1 at 20 mA/g current rate. The ultra small size of TiO2 nanocrystalline is beneficial for reaction kinetics, enhance the bulk intercalation of Mg ions, which remarkably increases storage capacity of TiO2. The discharge capacity over 100 cycles remains 105.2 mA h g−1, demonstrating the superiority of this material structure and its potential in magnesium ion batteries.

Lithium metal orthosilicates are attracting a lot of attention owing to their potential as high capacity and high energy-density cathode materials for Li-ion batteries. Although a number of studies have been performed on lithium metal silicates, understanding of the structure and electrochemical behaviour of Li2CoSiO4 has remained elusive. Herein, homogeneous nanocrystalline Li2CoSiO4/C composites have been synthesized directly by a sol-gel method using water-soluble silicon compounds. X-ray diffraction (XRD) analysis confirmed that the Li2CoSiO4 was well-crystallized in βI phase with Pbn21 space group. From the high resolution transmission electron microscopy (HRTEM) image, the lattice fringes of {001} and {100} are well-resolved. Selected area electron diffraction (SAED) pattern reveal the highly crystalline nature of Li2CoSiO4 and HRTEM image shows the carbon layer coating on particle surface. The Li2CoSiO4 cathode materials delivered an initial discharge capacity of 112 mAhg−1 at C/10 rate with good cyclic performance. The discharge profile of Li2CoSiO4 shows a plateau at 4.1 V, revealing its importance as high potential voltage cathode for high energy-density battery.

The modified Al-MCM-41 solid acids with turning Si/Al molar ratio were successfully fabricated through a hydrothermal route and utilized as a suitable catalyst in the cellulose conversion into 5-hydroxylmethylfurfural (5-HMF). The crystal structure, composition, morphologies and porosity of as-synthesized acids were characterized by XRD, FT-IR, N2 adsorption-desorption, TEM and EDS. The 27Al MAS NMR and 29Si-MAS NMR results revealed the existence of both Al framework and Al extra framework. Besides, the existence of medium-weak and strong acid sites, according to Bronsted and Lewis acidity, in Al-MCM-41 acids was confirmed by NH3-TPD and FTIR-pyridine adsorption. The 30Al-MCM-41 solid acid (Si/Al molar ratio = 30) exhibited excellent activity with the highest 5-HMF yield of 40.56% compared to other samples. We also discovered that 5-HMF production, as well as cellulose conversion, strongly depended on the total acid, strong/medium-weak acid ratio, as well as Bronsted/Lewis acid ratio. Therefore, these parameters have been considered as essential factors for the design of solid acid for 5-HMF production.

In the present study, we investigated the removal of an emerging pesticide lindane from aqueous solution using synthesized aluminum hydroxide Al(OH)3 (bayerite) nanomaterials with surface modification by an anionic surfactant sodium dodecyl sulfate (SDS). The Al(OH)3 nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunauer&ndash, Emmett&ndash, Teller (BET) and zeta potential. The lindane removal using SDS-modified nano-aluminum hydroxide nanoparticles (SMNAH) achieved removal of up to 93.68%, which was 3.3 times higher than that of nano-aluminum hydroxide nanoparticles. The adsorptive removal conditions were studied and found to have an adsorption time of 60 min, a pH of 6, an adsorbent dosage of 25 mg/mL and an ionic strength of 10 mM NaCl. After reusing four times, the removal efficiency of lindane using SMNAH still reached 75%. Two-step adsorption can fit adsorption isotherms of lindane onto SMNAH at two salt concentrations. On the basis of the change in zeta potential, surface functional groups and adsorption isotherms, we suggest that the formation of a bilayer micelle induced the removal of lindane.

We report the adsorption characteristics and mechanisms of a strong polyanion, poly(styrenesulfonate), PSS, onto α-Al2O3 with large size (L-Al2O3) and small size (S-Al2O3) in this paper. Some effective conditions to the adsorption of PSS onto L-Al2O3 and S-Al2O3 such as adsorption time, pH, mass ratio of PSS to α-Al2O3, and ionic strength were systematically studied. Maximum adsorption capacities of PSS onto both L-Al2O3 and S-Al2O3 were achieved with adsorption time 120 min, mass ratio of PSS to α-Al2O3 20 mg/g, and ionic strength 50 mM NaCl. The PSS adsorption onto S-Al2O3 significantly decreased with increasing pH from 4 to 9 while PSS adsorption onto L-Al2O3 decreased insignificantly in the pH range 4–9. Adsorption of PSS onto both L-Al2O3 and S-Al2O3 increased with increasing salt from 0 to 50 mM NaCl, indicating that electrostatic and none-lectrostatic interactions controlled adsorption at low ionic strength. However, adsorption of PSS was independent on the ionic strength at salt concentration higher than 50 mM. The changes in surface charge after PSS adsorption onto L-Al2O3 and S-Al2O3 were determined by zeta potential while the differences of surface functional groups before and after PSS adsorption were characterized by Fourier-transform infrared spectroscopy (FT-IR). The zeta potential as a function of the mass ratio of PSS to L-Al2O3 and S-Al2O3 agreed well with the adsorption capacity against the mass ratio. Adsorption mechanisms of PSS onto L-Al2O3 and S-Al2O3 were also discussed based on the changes in zeta potential, the differences of surface functional groups, and adsorbed amount as a function of the mass ratio of PSS to α-Al2O3.

Nanorod-based rutile TiO2 microspheres composed of numerous single-crystalline nanorods are successfully fabricated by hydrothermal treatment of peroxo titanic acid in acidic solution. The formation of highly oriented nanorod-based microspheres can be explained in view of crystal growth under the coordination chemistry rule, followed by particle attachment and coalescence. As anodes for Li-ion batteries, the TiO2 microsphere electrodes show enhanced rate performance, deliver a high reversible specific capacity of 180 mAh g−1 at 0.2 C (33.6 mA g−1) and 85.6 mAh g−1 at an extremely high rate of 50 C with an outstanding retention of 47.5%. These remarkable electrode properties are attributed to the efficient electron-transport by the hierarchical conductive pathway which promoted electronic conductivity and the shortened Li+ diffusion length resulting from the ultrafine nanorod structure.

Europium-doped yttrium picolinate microspheres have been synthesized by a facile aqueous solution method using picolinic acid as complexing as well as structure-directing agents. The synthesized particles are composed of microspheres with europium-doped yttrium picolinate nanohybrids as building blocks which are stacked together driven by mutual interactions of organic components. The formula of undoped hybrid was determined as Y(OH)2(C6H4NCOO)•1.5H2O based on thermogravimetry (TG), elemental analysis and Fourier transform infrared (FT-IR) spectroscopy. The formation of the hybrid microspheres can be explained on the basis of metal-ligand complexation and self-assembly through π-π interactions. Picolinic acid was found to play dual roles as chelating and structure-directing agents for manipulating the particle morphology. The europium-doped yttrium picolinate shows strong red luminescence due to an efficient energy transfer from pyridyl rings to luminescent Eu centers.

A pathway to access 11-substitued 11H-indolo[3,2-c]quinolines is described. The protocol features a chemoselective Suzuki reaction of ortho-dihaloquinolines with ortho bromophenylboronic acid, followed by a double C-N coupling with primary amines. The molecular structure of a representative product is exemplified, demonstrating well defined pi-stacking interactions in the molecular network.

Rutile TiO2 nanocrystals with exposed high-index facets have been investigated in detail by high-resolution transmission electron microscopy (HR-TEM) and selected-area electron diffraction (SAED). It was found that the each branched nanocrystal is bound by 4 facets of high-index {331}. Additionally, rutile {101} twinned structures are formed in the boundary of branches during the growth of multi branches in a hierarchical flower-like nanostructures. Notably, the synthesized nanostructures showed significantly higher photocatalytic activities than that of rod particles with exposed {110} facets in photocatalytic CO2 reduction. Correlating the presence of high-energy surface on rutile nanocrystals with the photocatalytic activity clearly shows the significant role of surface steps in enhancing intrinsic activity for CO2 reduction to methanol.