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Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. In this study, a series of predominant strains were isolated and identified as Enterobacter sp. with remarkable IAA-producing capabilities. The IAA-producing strains are mainly tryptophan-dependent and have significantly high yields of IAA (3477 μg mL−1 and 3378 μg mL−1). The ipdC gene encoding indole-3-pyruvate decarboxylase was identified by genomic analysis and RT-qPCR analysis, indicating the involvement of the indole-3-pyruvic acid (IPyA) pathway of IAA biosynthesis. The IPyA pathway was also confirmed by the intermediate assay. The IAA product of microbial metabolites was isolated, purified and characterized. These microbes exhibiting IAA production significantly promoted the growth of maize, increasing root length, plant height, fresh weight and dry weight. Thus, Enterobacter sp. with high IAA production has great prospects in agricultural and industrial applications.

Mono-cationic ionic liquids (MILs) have been widely utilized for the treatment of lignocelluloses. However, the hydrophilic property of MILs increases the difficulty of isolating sugars and their reuse, which limits their industrial application. In the present study, a series of dicationic ionic liquids (DILs) were synthesized with totally different di-cations and di-anions. An alternating miscibility of DILs with water was observed depending on the dealing temperature. The functional DILs exhibiting hydrophobic and acidic properties were investigated for the treatment of corn stalk. High yields of sugars were achieved as 27.8% and 31.6% with DIL3 and DIL4, respectively. Cellulosic materials were obtained as 74.3% and 77.8% with DIL1 and DIL2 and 61.2% and 65.7% with DIL3 and DIL4, respectively. Enzymatic reaction was successfully performed with cellulosic materials after the DIL treatment. DILs were recycled and reused with no significant reduction in sugar yields. Hydrophobic DILs are a potentially effective approach to enable the successful decomposition and degradation of lignocellulosic biomass.

Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. In this study, a series of predominant strains were isolated and identified as

Plant surface waxes form an outer barrier that protects the plant from many forms of environmental stress. The deposition of cuticular waxes on the plant surface is regulated by external environmental changes, including light and dark cycles. However, the underlying molecular mechanisms controlling light regulation of wax production are still poorly understood, especially at the posttranscriptional level. In this paper, we report the regulation of cuticular wax production by the miR156-SPL9 (SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9) module in Arabidopsis (Arabidopsis thaliana). When compared with wild-type plants, miR156 and SPL9 mutants showed significantly altered cuticular wax amounts in both stems and leaves. Furthermore, it was found that SPL9 positively regulates gene expression of the alkane-forming enzyme ECERIFERUM1 (CER1), as well as the primary (1-) alcohol-forming enzyme ECERIFERUM4 (CER4), to enhance alkane and 1-alcohol synthesis, respectively. Our results indicate that complex formation of SPL9 with a negative regulator of wax synthesis, DEWAX, will hamper SPL9 DNA binding ability, possibly by interfering with SPL9 homodimerization. Combined with their diurnal gene and protein expressions, this dynamic repression-activation transcriptional module defines a dynamic mechanism that may allow plants to optimize wax synthesis during daily cycles. These findings provide a regulatory framework for environmental signal integration in the regulation of wax synthesis.

A series of organic dyes based on quinoline as an electron-deficient π-linker, were designed and synthesized for dye sensitized solar cells (DSSC) application. These push-pull conjugated dyes, sharing same anchoring group with distinctive electron-rich donating groups such as N,N-diethyl (DEA-Q), 3,6-dimethoxy carbazole (CBZ-Q), bis(4-butoxyphenyl)amine (BPA-Q), were synthesized by Riley oxidation of CH3 followed by Knoevenagel condensation of the corresponding aldehyde precursors 2a-c with cyanoacrylic acid. The optical, electrochemical, theoretical calculation and photovoltaic properties with these three dyes were systematically investigated. Compared to DEA-Q and CBZ-Q, BPA-Q possesses better light harvesting properties with regard to extended conjugate length, red-shifted intramolecular charge transfer band absorption and broaden light-responsive IPCE spectrum, resulting in a greater short circuit photocurrent density output. BPA-Q also has improved open-circuit voltage due to the apparent large charge recombination resistance. Consequently, assembled with iodine redox electrolytes, the device with BPA-Q achieved the best overall conversion efficiency value of 3.07% among three dyes under AM 1.5G standard conditions. This present investigation demonstrates the importance of various N-substituent chromophores in the prevalent D-π-A type organic sensitizers for tuning the photovoltaic performance of their DSSCs.

We have cooperated with University of Stuttgart effectively on dual system education. In the light of the characteristics of students in China, we mainly adjusted and revised German teaching plan and teaching practice of dual teaching mode to fit the requirement of the students in our country. On this basis, we have made five-year practice exploration in cultivating the students majoring in mechanics. The results show that for applied undergraduate colleges and universities, adopting the dual system education has a good role in improving students’ practical ability, professional ability and employment ability. At the same time, it also helps to cultivate the students' team cooperation spirit.

A series of novel 2,6-conjugated Bodipy metal-free organic dyes (UY5–8) with phenothiazine (PTZ) moiety as electron donor for the dye-sensitized solar cells (DSSCs) have been designed and synthesized. The optical, electrochemical properties and photovoltaic performances are extensively investigated. The structure–property relationship shows that the introduction of various auxiliary conjugated spacers and anchoring groups are favorable to changing the efficiency of DSSCs. Among these dyes, UY7 comprised of furan with lower resonance energy as linker and cyanoacetic acid unit as electron acceptor possesses a flatter structure and longer electron recombination lifetime. Hence, a DSSCs using UY7 showing best photovoltaic performance with a short-circuit photocurrent density (Jsc) of 13.64 mA cm−2, an open-circuit photovoltage (Voc) of 590 mV and a fill factor (ff) of 0.66, corresponding to an overall conversion efficiency (η) of 5.31% under 100 mW cm−2 simulated AM 1.5 G solar irradiation. This is the best reported result in the solar cell with a Bodipy dye as photosensitizer.

Using γ-Al2O3 nanoparticles and 8-Hydroxyquinoline（8-HQ） as the raw materials, a novel fluorescent material, γ-Al2O3 /8-HQ nanocomposites were firstly synthesized by a simple heat refluxing method. The samples were characterized by transmission electron microscope (TEM), Fourier transformation infrared spectroscopy (FTIR) and photoluminescence spectroscopy. It is showed that chemical bonds had formed between the surface atoms of γ-Al2O3 nanoparticles and 8-HQ molecules. The PL intensity of γ-Al2O3 / 8-HQ nanocomposites was higher than that of both 8-HQ andγ-Al2O3 nanoparticles. Besides, the peak wavelength (488 nm) of the nanocomposite shows a blue shift of 135nm compared with that (623 nm) of 8-HQ particles. In addition, the effect of 8-HQ concentrations on the photoluminescence of nanocomposites was also studied.

On 25 June 1990, a radiation accident occurred in a (60)Co source radiation unit in Shanghai, due to violations in operation regulations. This accident resulted in the exposure of seven individuals to acute high-dose and dose-rate whole-body external irradiation. Conventional chromosomal aberration analysis, G-banding automatic karyotype analysis and/or fluorescent in situ hybridization (FISH) painting methods were used to analyze chromosomal aberrations in peripheral blood lymphocytes from five of the victims 24 h to 17 years after accidental exposure to 1.9-5.1 Gy of (60)Co gamma-rays. The frequency of unstable chromosomal aberrations (dicentrics and rings) remained at constant levels 1 month after exposure. Three months after exposure, the frequency was reduced by 20-40% in three victims, while no reduction was seen in the other two victims. Twelve years after exposure, the number of dicentrics and rings decreased by more than 90%, and did not reveal a dose-dependent relationship. However, even at 12-17 years after exposure, stable chromosome aberrations, dominated by translocations, remained at a high level in a dose-dependent manner. The frequency of stable chromosomal aberrations detected by FISH showed a similar dose-dependent relationship as that detected by karyotype analysis of G-banding chromosomes. The G-banding analysis also suggested that the pattern of chromosome breakpoints is random. The FISH data showed a decreasing tendency with time for chromosome translocation frequency in the peripheral lymphocytes, and the rate of reduction varied among different individuals. It is likely that the higher dose the victim received, the lesser the translocation frequency decreased with time. The G-banding data also showed that the rate of reduction of translocations is different among individuals. From 5 to 17 years after accidental irradiation, a very small reduction (approximately 10%) of translocation frequency was observed in victims C and D, while there was about a 35% reduction (the highest among the victims) for victim G who received the smallest dose (1.9 Gy). These observations can be used to validate the existence of chromosomal aberrations in peripheral blood lymphocytes as a biological dosimeter for radiation exposures.