Banana fiber, a waste product of banana cultivation, has been used to prepare banana fiber reinforced soy protein composites. Alkali modified banana fibers were characterized in terms of density, denier and crystallinity index. Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) were also performed on the fibers. Soy protein composites were prepared by incorporating different volume fractions of alkali-treated and untreated fibers into soy protein isolate (SPI) with different amounts of glycerol (25%–50%) as plasticizer. Composites thus prepared were characterized in terms of mechanical properties, SEM and water resistance. The results indicate that at 0.3 volume fraction, tensile strength and modulus of alkali treated fiber reinforced soy protein composites increased to 82% and 963%, respectively, compared to soy protein film without fibers. Water resistance of the composites increased significantly with the addition of glutaraldehyde which acts as crosslinking agent. Biodegradability of the composites has also been tested in the contaminated environment and the composites were found to be 100% biodegradable.

In this review, some living organisms with multilevel hierarchical micro/nanostructures and related special properties are briefly introduced. The unique properties of organisms are mostly related to their special hierarchical micro/nanostructures. Inspired by nature, many zero-dimensional and one-dimensional micro/nanomaterials with biomimic or bioinspired multilevel micro/nanostructures have been successfully synthesized and prepared in recent years. Compared with traditional solid materials, the synthesis and preparation of these multilevel structured materials is more ingenious. Moreover, these kinds of multilevel micro/nanomaterials show fantastic properties in many fields because of their micro/nanoscale complex interior structures, which may be intended for application in catalysis, Li-ion batteries, biomedicines, sensors, and others.

Electron transfer (ET) rate is a fundamental parameter to characterize ET processes in physical, chemical, material and biologic sciences. It is affected by a number of quantum phenomena, such as nuclear tunneling, curve crossing, quantum interference, and the coupling to the environment. It is thus a challenge to accurately evaluate the ET rate since one has to incorporate both quantum effects and dissipation. In this review article, we present several semiclassical theories proposed in our group to cover the regime from weak to strong electronic coupling. Their applications to some concrete systems are also shown.

Divergently synthesized carbosilane dendrimers generations 1 (G1) and 2 (G2) with allyl end groups were bonded onto silica gel. Reactions between the dendrimers and acid-processed silica gel took place, with toluene reflux and organic base as catalyst. Chemically bonded silica gel was characterized by transmission electron microscopy (TEM), infrared (IR)?and other methods. The chemically modified silica gels were packed into high-pressure liquid chromatography (HPLC) column and their separation characters were evaluated. G2-bonded silica gel was effective in separating homologous compounds of alcohol, alkyl-substituted benzene, N-substituted benzene, metacrylic acid ester and phthalate.

2-Methylthiophene (1) was treated at 0°C with liquid bromine to form 3,5-dibromo-2-methylthiophene (2) which reacted with tributyl borate to give 2-methyl-3-bromo-5-boronate thiophene (3) at -78°C. Treatment of 3 with 3,4-difluorobrombenzene gave 2-methyl-3-bromo-5-(3,4-difluorophenyl)thiophene (4). Finally, a novel photochromic dithienylethene compound, 1,2-bis[2-methyl-5(3,4-difluorophenyl)-3-thienyl]perfluorocyclopentene (DT-1), was synthesized by the reaction of 4 with perfluorocyclopentene at -78°C. The compound (DT-1) was characterized by IR, NMR, MS, elemental analysis and its photochromic behavior was also discussed.

In physicochemical studies on the sea-surface microlayer (SML) in seawater, the main researches conducted were as follows: (1) It was found that there is an objective layer of sudden change in physical and chemical properties between the SML and the subsurface layer in seawater. (2) The SML thickness was determined and should be about 50?10 ?m. (3) The Gibbs model of the SML was extended, and the multilayer model of the SML was advanced. (4) The original-location method, which corresponds with the traditional removal-location method, was founded and used to determine the SML thickness. The results obtained from the two methods were almost identical. (5) An abnormal phenomenon was found when the Gibbs solution adsorption was applied to the seawater system, the reason for which was discussed preliminarily.

The major progress in organic synthesis since 2005 is briefly surveyed in two parts. The first part deals with some of the most impressive advances in the synthetic methodology, which includes: (1) metal-mediated synthetic reactions, with an emphasis on the olefin metathesis and gold-mediated reactions; (2) free radical-based organic synthesis; (3) synthetic transformations performed in a one-pot  manner involving either tandem reactions or multicomponent reactions; (4) asymmetric reactions catalyzed by metal and organo-catalysts. The major advances in total synthesis of some complex natural products with significant biological activities are presented in the second part, with detailed illustrations of ten selected molecules, including dragmacidin F, abyssomicin C, 11-acetoxy-4-deoxyasbestinin D, pentacycloanammoxic acid, UCS1025A, (−)-merrilactone A, nigellamine A₂, (+)-saxitoxin, and Tamiflu (an artificially designed natural product-like molecule). An array of complicated structures of the natural products synthesized over the last two years is also listed to serve as a convenient lead to the original literature for the prospective interested readers.

Photocatalytic splitting of water into H₂ is one of the most promising ways for converting solar energy into chemical energy. In the present paper, the basic physical and chemical principles of photocatalysts for hydrogen generating from aqueous solutions are outlined. Strategies for designing visible-light-induced photocatalysts have been reviewed. Besides, ultraviolet-light-induced photocatalysts, dye sensitization, photoelectrochemical water splitting and Z-scheme systems to effectively increase the light harvest are also discussed. Finally, the existing problems, possible solutions and prospects are presented.

Chlorosulfonyl-containing naphthol azo compounds were prepared by reaction of the corresponding sulfonate-containing naphthol azo dyes with thionyl chloride in the presence of a catalytic quantity of N,N-dimethylformamide and various solvents. The yields and reaction selectivity of chlorosulfonyl-containing naphthol azo compounds were discussed according to the properties of solvents. It was demonstrated that high chemical selectivity and high yield were achieved by using benzene, toluene or thionyl chloride as solvent. Additionally, on account of unstable properties of sulfonyl chloride compounds in MS and ¹H-NMR analyses, a new analytical method using stable sulfonamide is put forward to verify the chemical structures of the corresponding sulfonyl chloride compounds indirectly.

Nonlinear optical (NLO) crystals have been playing an increasingly important role in laser science and technology. The NLO crystals used in the middle infrared (mid-IR) region, compared with the NLO crystals in the other wavelength regions, are still not good enough for the application of high-energy laser. The main defect is that their laser damage thresholds (LDT) are low. Chinese scientists have made a lot of important contributions to the UV and visible NLO crystals. In the last decade, they also did a lot of work on the mid-IR NLO materials. The main purpose of these researches is to increase the LDT and simultaneously balance the other properties. This paper presents a brief summary of their research progress in this topic on three types of materials: chalcogenides, oxides, and halides. The emphasis is put on the design strategy and quality control of the crystals.

Dehydrated ammonium carnallite was synthesized with bischofite from salt lake and ammonium chloride solution in a 1:1 molar ratio of MgCl₂:NH₄Cl, dehydrated at 160ºC for about 4 h. The yield was above 85%. The product was then mixed with solid-state ammonium chloride with a 1:4 mass ratio for the further dehydration at 410ºC. The decomposition of NH₄Cl made a pressure of NH₃ at 30.5 kPa to prevent the hydrolysis of ammonium carnallite. The anhydration of magnesium chloride was achieved at 700ºC. The results showed that anhydrous magnesium chloride contains magnesium oxide in an amount that was less than 0.1% by weight. XRD pattern and SEM micrograph showed a good dispersion of ammonium carnallite and anhydrous magnesium chloride crystals with well-distributed big grains, just enough to meet the need for the production of magnesium metal in the electrolysis process.

The synthesis of cyclic carbonates or dimethyl carbonate (DMC) using CO₂ as a building block is a very interesting topic. In this work, we found that the metal-organic framework-5 (MOF-5)/KI was an active and a selective catalytic system for the synthesis of cyclic carbonates from CO₂ and epoxides, and MOF-5/KI/K₂CO₃ was efficient for the preparation of DMC from CO₂, propylene, and methanol by a sequential route. The impacts of temperature, pressure, and reaction time length on the reactions were investigated, and the mechanism of the reactions is proposed on the basis of the experimental results.

Low-costsensors with high sensitivity and selectivity for chemical and biological detection are of high scientific and economic importance. Silica nanoparticles (NPs) have shown vast promise in sensor applications by virtue of their controllable surface modification, good chemical stability, and biocompatibility. This mini-review summarizes our recent development of silica NP-based assays for chemical and biological detection, where silica NPs serve as the substrate for probe immobilization, target recognition, and separation. The assay performance is further improved through the introduction of conjugated polyelectrolyte to amplify the detection signal. The assays have been demonstrated to be successful for the detection of DNA, small molecules, and proteins. They could be generalized for other targets based on specific interactions, such as DNA hybridization, antibody-antigen recognition, and target-aptamer binding.

Theoretical work related to the self-assembly of organic materials was dealt with, and the various mechanisms leading to self-assembly, such as transition metal mediated self-assembly, constraint induced self-assembly, covalent bond based self-assembly and van der Waals interaction driven self-assembly, etc., were discussed. The formation of ordered structures could be attributed to the competition between short range attractive forces and long-range repulsion, which was arising from dipole interaction or may result from a different mechanism based on a purely repulsive isotropic short-range pair potential with two characteristic length scales. Such mechanism could be exploited in the study of self-assembly process. First principles SAPT(DFT) interaction energy calculations, combined with the Williams-Stone-Misquitta method, offer the ability to improve the molecular dynamics (MD) accuracy which could in turn be used in the prediction of crystal structures and self-assembly tendency. The combination of experimental and theoretical studies could open new breakthroughs over the design, synthesis, and characterization of self-assembled materials.

The action of the three kinds of new third generation cephalosporin-class drugs, cefepime hydrochroride, cefpiramide and ceftizoxime with HSA and BSA was studied at different temperatures through the fluorescence method. First, the binding constants were calculated by using fluorescence quenching and enhancement theoretical equations. Their thermodynamic functions were also calculated. Because the K_A corresponding to the different theoretical equations are not completely the same, the thermodynamic parameters calculated are also different. In this paper, the differences among these thermodynamic data obtained from the different theoretical equations were analyzed and the results show that the thermodynamic data deduced from fluorescence enhancement are more reasonable. Thus, we propose that even when the fluorescence quenching action of the acceptor-substrate is studied, more realistic data can be obtained by using the fluorescence enhancement equation.

Electronic band structure is one of the most important intrinsic properties of a material, and is in particular crucial in electronic, photo-electronic and photo- catalytic applications. Kohn-Sham Density-functional theory (KS-DFT) within currently available local or semi-local approximations to the exchange-correlation energy functional is problematic for the description of electronic band structure. Many-body perturbation theory based on Green’s function (GF) provides a rigorous framework to describe excited-state properties of materials. The central ingredient of the GF-based many-body perturbation theory is the exchange- correlation self-energy, which accounts for all non-classical electron-electron interaction effects beyond the Hartree theory, and formally can be obtained by solving a set of complicated integro-differential equations, named Hedin’s equations. The GW approximation, in which the self-energy is simply a product of Green’s function and the screened Coulomb interaction (W), is currently the most accurate first-principles approach to describe electronic band structure properties of extended systems. Compared to KS-DFT, the computational efforts required for GW calculations are much larger. Various numerical techniques or approximations have been developed to apply GW for realistic systems. In this paper, we give an overview of the theory of first-principles Green’s function approach in the GW approximation and review the state of the art for the implementation of GW in different representations and with different treatment of the frequency dependence. It is hoped that further methodological developments will be inspired by this work so that the approach can be applied to more complicated and scientifically more interesting systems.

ZnO nanorings were synthesized on a large scale by an easy solution-based method at 70°C for 5 h using hexamethylenetramine (C₆H₁₂N₄, HMT) and Zn(NO₃)₂·2H₂O as raw materials in the presence of surfactant poly(acrylamide-co-diallyldimethylammonium chloride) (PAM-CTAC). The structure and morphology of the products were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The influence of experimental conditions such as concentration of surfactant and reactants, reaction temperature on the structure and morphology of the products were investigated. A probable formation mechanism of ZnO nanorings in the presence of surfactant PAM-CTAC was discussed. The results show that the products are wurtzite hexagonal ZnO nanorings with an inner diameter of 220 nm and a wall thickness of 70 nm. Reaction temperature and concentration of reactants influence the shape and size of ZnO nanorings but PAM-CTAC plays the key role in the formation of ZnO nanorings. Through adjusting the concentration of PAM-CTAC, controlled-synthesis of ZnO nanorings can be realized. A room temperature photoluminescence (PL) spectrum of ZnO obtained shows that the full width at half maximum (FWHM) of the UV emission (∼ 7 nm) is much narrower than that of commercial ZnO bulk crystals (∼ 18 nm). The narrow FWHM confirms the uniformity and narrow size distribution of the synthesized ZnO crystals.

Sum frequency generation (SFG) vibrational spectroscopy has been proved to be a powerful technique which substantially impacts on many research areas in surface and interfacial sciences. This paper reviews the recent progress of applying this nonlinear optical technique in the studies of polymer surfaces and interfaces. The theoretical background of SFG is introduced first. Current applications of SFG in polymer science are then described in more detail to demonstrate the significance of this technique. Finally, a short summary is presented on this relatively new but widely applicable spectroscopic technique.

A series of polyurethanes modified by polysiloxane (Si-PU) were synthesized based on 2,4-toluene diisocyanate (TDI), dihydroxybutyl-terminated polydimethylsiloxane (DHPDMS), polytetramethylene glycol (PTMG) and 1,4-butanediol (BDO). Fourier transform infrared spectroscopy analysis showed that DHPDMS had been incorporated into the polyurethane chains. With the increase of DHPDMS content, the water contact angle increased while the surface tension decreased. As the DHPDMS content increases above 5%, both the contact angle and the surface tension tend to approach a constant. The contact angle increases with increasing temperature, and it tends to approach a constant when the temperature is higher than 50°C. The result indicates that Si-PU exhibits good surface and mechanical properties when the DHPDMS content is 5%.

Organic photovoltaic materials are of interest for their future applications in solar cells. Compared to inorganic or dye-sensitized solar cells, organic photovoltaic (OPV) cells offer a huge potential for low-cost large-area solar cells because of their low material consumption per area and easy processing. In the last few years, there have seen an unprecedented growth of interest in OPVs with power conversion efficiency of over 5% attainable. However, OPV’s performance is limited by the narrow light absorption, poor charge carries mobility, and low stability of organic materials, all of which confine its large-scale commercial applications. This review will develop a discussion on the OPV device configuration and operational mechanism after an introduction of the general features of OPV materials. Subsequently, the typical progresses in materials development and performance evolution in recent years will be summarized. The future challenges and prospects faced by organic photovoltaics will be discussed. Finally, the innovative strategy on research of molecular design and device optimization will be suggested with the aim for practical application.

Gold nanoparticles were prepared via a simple photoreduction technique in the presence of transition metal monosubstituted Keggin heteropolyanions (PW11M, M= Cu²⁺, Ni²⁺, Zn²⁺, Fe³⁺), in which PW11M acted as reducing agent, photocatalyst and stabilizer. The results indicated that the formation rate and morphology of the nanoparticles strongly depended on the kind of transition metal substituted in heteropolyacid and the preparation conditions, such as irradiation time and propan-2-ol amount. The photoreduction rates of PW11Zn and PW11Fe were faster than those of PW11Ni and PW11Cu. The shapes of the nanoparticles synthesized in the presence of PW11Fe and PW11Zn were nearly uniform spheres, whereas the morphologies of the nanoparticles synthesized in the presence of PW11Ni and PW11Cu were found to contain a mixture of flat triangular/hexagonal structures as well as spheres. Increases in the irradiation time and the propan-2-ol amount could make the morphology of nanoparticles uniform and shorten the formation time of the nanoparticles.

Qinghaosu (QHS) and its derivatives are a new generation of antimalarial drugs characterized by fast action, high efficacy, and good tolerance. This feature article states the discovery of QHS from traditional Chinese medicine qinghao (Artemisia annua L.) and reviews the progress during the past four decades in the research of phytochemistry of A. annua, chemical reactions and biotransformation of QHS, chemical synthesis and biosynthesis of QHS, synthesis and antimalarial activity of QHS derivatives and analogs, pharmacological studies, clinical application, and the antimalarial mechanism. Undoubtedly, QHS is an example of the value of traditional Chinese medicine in modern medicinal research.

The studies over forty years on rare earth catalysts in polymer syntheses of diene, alkyne, alkylene oxide, thiirane, carbon dioxide copolymerization, lactide, caprolactone, cyclic carbonate and so forth in China have been reviewed.

The bioreaction mechanism and kinetic behavior of protein enzymatic hydrolysis for preparing active peptides were investigated to model and characterize the enzymatic hydrolysis curves. Taking into account single-substrate hydrolysis, enzyme inactivation and substrate or product inhibition, the reaction mechanism could be deduced from a series of experimental results carried out in a stirred tank reactor at different substrate concentrations, enzyme concentrations and temperatures based on M-M equation. An exponential equation dh/dt = aexp(-bh) was also established, where parameters a and b have different expressions according to different reaction mechanisms, and different values for different reaction systems. For BSA-trypsin model system, the regressive results agree with the experimental data, i.e. the average relative error was only 4.73%, and the reaction constants were determined as Km = 0.0748 g/L, K_s = 7.961 g/L, kd = 9.358/min, <>emk2 = 38.439/min, E_a = 64.826 kJ/mol, Ed = 80.031 kJ/mol in accordance with the proposed kinetic mode. The whole set of exponential kinetic equations can be used to model the bioreaction process of protein enzymatic hydrolysis, to calculate the thermodynamic and kinetic constants, and to optimize the operating parameters for bioreactor design.

A series of segmented poly(L-lactide)-polyurethanes (PLA-PUs) were synthesized by a twostep method, with oligo-poly(L-lactide) (PLA) as the soft segments and the reaction product of 2,4-toluene diisocyanate (TDI) and ethylene glycol (EG) as the hard segments. The shape-memory properties and biocompatibility of PLA-PUs were examined. The 50% compressed PLA-PUs could recover almost 100% to their original shape within 10! from the lowest recovery temperature (22!-37!). In the recovery process the PLA-PU showed a maximum contracting stress in the range of 1.5-4 MPa. Cell incubation experiments show that PLA-PU has biocompatibility comparable to that of pure PLA. Therefore, this kind of polyurethane can be used for implanted medical devices with shape memory requirements.

Using glycerol as electron donor, photocatalytic hydrogen generation over Pt/TiO₂ was investigated. The results show that glycerol can not only improve the efficiency of photocatalytic hydrogen generation but can also be decomposed effectively. The factors which affect photocatalytic hydrogen generation, such as irradiation time, initial concentration of the glycerol solution, pH-value of the suspensions and the coexisting substances were studied. The final oxidation products of glycerol were H₂O and CO₂. Glyceraldhyde, glycoladehyde, glycolic acid and formaldehyde were identified as the intermediates. A possible reaction mechanism was discussed.

Nano-sized cobalt particles with the diameter of 2 nm were prepared via an organic colloidal process with sodium formate, ethylene glycol and sodium citrate as the reducing agent, the solvent and the complexing agent, respectively. The effects of sodium citrate on the yield, crystal structure, particle size and size distribution of the prepared nano-sized cobalt particles were then investigated. The results show that the average particle diameter decreases from 200 nm to 2 nm when the molar ratio of sodium citrate to cobalt chloride changes from 0 to 6. Furthermore, sodium citrate plays a crucial role in the controlling of size distribution of the nano-sized particles. The size distribution of the particle without sodium citrate addition is in range from tens of nanometers to 300 or 400 nm, while that with sodium citrate addition is limited in the range of (2±0.25) nm. Moreover, it is found that the addition of sodium citrate as a complex agent could decrease the yield of the nano-sized cobalt particle.

Ionic liquid like 1-butyl-3-methyl- imidazolium tetrafluorobrate ([BMIM]BF4) has been used as solvent and electrolyte for the electropolymerization of aniline at glassy carbon electrode by cyclic voltammetry. Electrode modified with polyaniline (PAn) has obvious electrochemical activity in ionic liquid and acid solution (pH 0-4), and has significant electrocatalytic activity for redox reaction of catechol and hydroquione.

Surface plasmon resonance (SPR) can provide a remarkably enhanced electromagetic field around metal surface. It is one of the enhancement models for explaining surface-enhanced Raman scattering (SERS) phonomenon. With the development of SERS theories and techniques, more and more studies referred to the configurations of the optical devices for coupling the excitation and radiation of SERS, including the prism-coupling, waveguide-coupling, and grating-coupling modes. In this review, we will summarize the recent experimental improvements on the surface plasmon-coupled SERS.