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The design of photochemical molecular devices (PMDs) for photocatalytic H2 production from water is a meaningful but challenging subject currently. Herein, a Pd2 L4 type metal-organic cage (denoted as MOC-Q2) is designed as a PMD, which consists of two catalytic centers (Pd2+ ) and four photosensitive ligands (L-2) with four pyridine anchoring groups. Subsequently, the MOC-Q2 is combined with TiO2 to form TiO2 -MOC-Q2 hybrid materials with different MOC-Q2 contents by a facile sol-gel method, which have micro/mesoporous structures and large surface areas. The optimized TiO2 -MOC-Q2 (6.5 wt%) exhibits high H2 production activity (7.9 mmol g-1 h-1 within 5 h) and excellent durability, giving a TON value of 23477 or 11739 (based on MOC-Q2 or Pd moles) after recycling for 7 rounds. By contrast, the pure MOC-Q2 only shows an ordinary photocatalytic H2 production rate (0.84 mmol g-1 h-1 within 5 h) in the homogeneous system. It can be deduced that TiO2 drives the photocatalysis and simultaneously acts as the structure promoter. This study presents a meaningful and distinctive attempt of a new approach for the design and development of MOC-based heterogeneous photocatalysts.

A series of novel triphenylamine/carbazole-based D-D-π-π-A dyes DH1-4 and a mesoporous anatase cubic "microcage" TiO2 material (denoted as MC-TiO2 ) were synthesized and combined to obtain dye-sensitized photocatalysts (denoted as DHn/Pt/MC-TiO2 , n=1-4). These catalysts showed better performances in visible-light-driven H2 evolution from water than DHn/Pt/P25-TiO2 catalysts based on commercial P25-TiO2 bulk semiconductor under similar conditions. Compared with P25-TiO2 particles, the porous MC-TiO2 had a large Brunauer-Emmett-Teller surface area, porosity, and exposed {0 0 1} crystal plane, which greatly contributed to the photocatalytic activity. The optimized DH2/Pt/MC-TiO2 photocatalyst exhibited an attractive H2 production rate (16.28 mmol g-1 h-1 based on catalyst mass), and the optimized DH4/Pt/MC-TiO2 photocatalyst showed good stability [turnover number (TON) of 16 699 in 105 h based on dye number], which represents one of the best performances among all reported visible-light-driven heterogeneous catalytic systems. Compared with the other dyes in this series, the high H2 production rate of DH2 on Pt/MC-TiO2 can be attributed to its size-matching effect and thus high dye loading amount, whereas the high TON and durability of DH4/Pt/MC-TiO2 are probably related to the rapid regeneration kinetics of DH4.

Extra virgin olive oil has been one of the most common targets for economically motivated food adulteration. This research employed the hand‐held FTIR spectrometer to develop the simple and portable screening methods for extra virgin olive oils adulterated with other cheaper vegetable oils. With the help of the ATR probe and chemometrics tools, oil samples can be measured directly without any pretreatment, then the spectra can be interpreted automatically to determine the possibility of adulteration and estimate the content of adulterant oil. A feasibility study of the hand‐held FTIR screening method was carried out using olive oils adulterated with canola oil, peanut oil, corn oil, soybean oil, and sunflower oil. The SIMCA model using the hand‐held FTIR spectra can identify different kinds of vegetable oils correctly and recognize olive oils with not less than 10% of adulterant oils. Meanwhile, the content of adulterant oil in the range of 5% to 45% can be estimated by the PLS model using the hand‐held FTIR spectra within an error of 3%. This research shows the potential of the hand‐held FTIR technique in the rapid and field screening of olive oils adulterated with some cheaper vegetable oils. This research provide a rapid and automatic detection method for olive oils adulterated with other cheaper vegetable oils. An oil sample can be measured directly within one minute, and the hand‐held instrument can be used anywhere needed.

Objectives To determine the contrast-enhanced sonographic features of hepatic artery collateral transformation in patients with hepatic artery complications after liver transplantation. Methods Ninety-nine liver transplant recipients who underwent contrast-enhanced sonography were recruited from April 2004 to May 2014. The reference standards were conventional angiography and computed tomographic angiography. The contrast-enhanced sonographic features of the hepatic artery in patients with and without collateral arteries were retrospectively analyzed. Results All 15 patients with hepatic artery collateral transformation had hepatic artery thrombosis (10 of 15) or hepatic artery stenosis (5 of 15). The collateral artery detection rate on contrast-enhanced sonography was 100%. The peripheral hepatic artery could not be visualized by contrast-enhanced sonography in most of the patients with hepatic artery collateral transformation (14 of 15). Additionally, many small tortuous collateral arteries in the porta hepatis region were visualized during the arterial and early portal phases, showing reticulated/patchy (15 of 15) and striped (3 of 15) enhancement patterns on contrast-enhanced sonography. Conclusions Collateral transformation of the hepatic artery in patients with hepatic artery complications after liver transplantation appears to have characteristic features on contrast-enhanced sonography, especially a reticulated or patchy enhancement pattern in the porta hepatis region during the arterial and early portal phases combined with the absence of the peripheral hepatic artery. Contrast-enhanced sonography may be a novel method for diagnosing hepatic artery collateral transformation, which may be a highly specific sign of hepatic artery thrombosis or stenosis.

Alligator weed, Alternanthera philoxeroides (Mart.) Griseb., is one of the worst invasive weeds in the world. In the present study, the genome size of seven forms/biotypes of alligator weed from Argentina (native area), the USA (introduced area), and China (introduced area) was analyzed using flow cytometers; the ribosomal DNA internal transcribed spacer region (ITS) was cloned and sequenced. We found that the genome size of A. philoxeroides ranged from 5.72 to 8.50 pg/2C nucleus, consisting of four levels of genome and three kinds of ploidy. Among them, three levels and two kinds (tetraploid and hexaploid) were found in samples from Argentina, two levels and one kind (pentaploid) in US samples, and one level and one kind (hexaploid) in samples from China. Contrary to the significant variation in genome size, we found that the intraspecific differentiation of the ITS sequences in the seven forms/biotypes was extremely low, and that six of them shared ITS sequences with no or one single substitution. These results show that the change of genome size played a major role in the differentiation of A. philoxeroides, and that forms/biotypes with higher ploidy seem to have stronger invasive ability. Furthermore, the differences of A. philoxeroides in ploidy between samples from the USA and China showed that alligator weeds from these two invaded areas certainly have different native progenitors.

The method of molecular dynamics (MD) simulations was used to investigate the interaction between the PLA and the attapulgite, and the influence of the temperature on the mechanical properties of the PLA and the PLA-attapulgite. After the PLA blends the attapulgite, the structures and properties of the PLA and the attapulgite change due to their strong interaction. However, this interaction weakens gradually with temperature increasing. The isotropy of the composite of PLA-attapulgite is strengthened in comparison with the PLA. In addition, the temperature can change the mechanical properties of the PLA-attapulgite, but the mechanical properties of the PLA are hardly influences on the temperature. The PLA-attapulgite is more rigid and tough than the PLA at the room temperature but the toughness of the composite of PLA-attapulgite becomes worse than that of the PLA at 350 K. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Substrate selectivity of glycerol-3-phosphate acyltransferase (EC 2. 3. 1. 15) of rice (Oryza sativa L.) was explored in a comparative study of acyltransferases from seven plant species. In vitro labeling of acyl carrier protein (ACP) with (14)C or (3)H showed that acyltransferase from chill-sensitive plants, such as rice that uses either oleic (18:1) or palmitic acid (16:0) as acyl donor at comparable rates, displays lower selectivity than the enzyme from chill-resistant plants, such as spinach, which preferentially uses oleic acid (18:1) rather than palmitic acid (16:0) as an acyl donor. This may be a result of the size and character of the substrate-binding pocket of acyltransferase. Homology modeling and protein structure-based sequence alignment of acyltransferases revealed that proteins from either chill-sensitive or chill-tolerant plants shared a highly conserved domain containing the proposed substrate-binding pocket. However, the aligned residues surrounding the substrate-binding pocket are highly heterogeneous and may have an influence mainly on the size of the substrate binding pockets of acyltransferases. The substrate selectivity of acyltransferase of rice can be improved by enlarging the substrate-binding pocket using molecular biological methods.

The mechanisms and dynamics studies of the OH radical and Cl atom with CF3CHClOCHF2 and CF3CHFOCHF2 have been carried out theoretically. The geometries and frequencies of all the stationary points are optimized at the B3LYP/6-311G(d,p) level, and the energy profiles are further refined by interpolated single-point energies (ISPE) method at the G3(MP2) level of theory. For each reaction, two H-abstraction channels are found and four products (CF3CHFOCF2, CF3CFOCHF2, and CF3CHClOCF2, CF3CClOCHF2) are produced during the above processes. The rate constants for the CF3CHClOCHF2/CF3CHFOCHF2 + OH/Cl reactions are calculated by canonical variational transition-state theory (CVT) within 200–2000 K, and the small-curvature tunneling is included. The total rate constants calculated from the sum of the individual rate constants and the branching ratios are in good agreement with the experimental data. The Arrhenius expressions for the reactions are obtained. Our calculation shows that the substitution of Cl by F decreases the reactivity of CF3CHClOCHF2 toward OH and Cl. In addition, the mechanisms of subsequent reactions of product radicals and OH radical are further investigated at the G3(MP2)//B3LYP/6-311G(d,p) level, and the main products are predicted in the this article. © 2008 Wiley Periodicals, Inc. J Comput Chem 2009

In an attempt to explore the relationships between phosphatidylglycerol (PG) molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, electron transport activities of thylakoid membrane and the potential quantum yield (F(v)/F(m)) in rice treated under middle and low photon flux density (PFD) at 11 degrees C were analyzed by high performance liquid chromatography, enzyme hydrolysis, gas phase chromatography (GC) and so on. Results showed that the major molecular species of PGs in rice thylakoid membrane were 18:3/16:0, 18:3/16:1(3t), 18:2/16:0, 18:2/16:1(3t), 18:1/16:0, 18:1/16:1(3t), 16:0/16:0, 16:0/16:1(3t). There were large differences in the contents of unsaturated PG molecular species such as 18:1 approximately 3/16:0 approximately 16:1(3t) and saturated PG molecular species like 16:0/16:0 approximately 16:1(3t) among japonica cv 9516 (j-9516), japonica-indica hybrid F1 j-9516/i-SY63 (ji-95SY) and indica cv Shanyou 63 (i-SY63). J-9516 containing higher contents of unsaturated PG molecular species was manifest in stable D1 protein contents under chill and tolerant to chill-induced photoinhibition. In contrast to j-9516, i-SY63 with lower contents of unsaturated PG molecular species, exhibited unstable D1 protein contents under chill and was sensitive to chill-induced photoinhibition. ji-95SY containing middle contents of unsaturated PG molecular species between those of j-9516 and i-SY63, exhibited mid extent of sensitivity to chill-induced photoinhibition. The losses in D1 protein also account for the inhibition in electron transport activity of thylakoid membrane and the observed decline in F(v)/F(m). The PG molecular species that is efficient in raising chilling-resistant capacity were those containing unsaturated fatty acids, namely, unsaturated PG molecular species. These results implied that the substrate selectivity of the glycerol-3-phosphate acyltransferase in chloroplasts towards 16:0 or 18:1 displayed greatly the difference between japonica and indica rice. It was possible to enhance the capacity of resistance to chilling-induced photoinhibition by improving or modifying the GPAT gene.

Temperature is one of the abiotic factors limiting growth and productivity of plants. In the present work, the effect of low non-freezing temperature, as an inducer of “chilling resistance”, was studied in three cultivars of rice (Oryza sativa L.), japonica cv. 9516 (j-9516), the two parental lines of superhigh-yield hybrid rice between subspecies, Peiai/E32 (ji-PE), and the traditional indica hybrid rice Shanyou 63 (i-SY63). Leaves of chill-treated rice showed chilling-induced resistance, as an increase of their low-temperature tolerance was measured using chlorophyll fluorescence measurements, revealing a change in photosystem II (PSII) efficiency. After 5 d of exposure to 11°C under low light (100 μmol m-2 s-1), levels of unsaturated fatty acids in PSII thylakoid membrane lipids decreased during the initial 1-2 d, then increased slowly and reached 99.2%, 95.3% and 90.1% of the initial value (0 d) in j-9516, ji-PE and i-SY63, respectively, on the fifth day. However, under medium light (600 μmol m-2 s-1), all cultivars experienced similar substantial photoinhibition, which approached steady state levels after a decline in levels of unsaturated fatty acids in PSII thylakoid membrane lipids to about 57.1%, 53.8% and 44.5% of the initial values (0 d) in j-9516, ji-PE and I-SY63 on the fifth day. Under either chilling-induced resistance (the former) or low temperature photoinhibition (the latter) conditions, the changes of other physiological parameters such as D1 protein contents, electron transport activities of PSII (ETA), Fv/Fm, xanthophyl cycle activities expressed by DES (deepoxide state) were consistent with that of levels of unsaturated fatty acids in PSII thylakoid membrane lipids. So there were negative correlations between saturated levels of fatty acids (16:1(3t), 16:0, 18:0), especially the 16:1(3t) fatty acid on thylakoid membrane and other physiological parameters, such as D1 protein contents, ETA and (A+Z)/(A+V+Z). A specific role of desaturation of fatty acids and the photoprotective pigments of the xanthophyl cycle, leading to an acclimation response in thylakoid membrane lipids may be involved. We conclude that chilling-induced resistance is accelerated by the unsaturation of thylakoid membranes, and the ability of rice plants to cold-harden can be enhanced by genetic engineering.

An efficient approach for the one-pot synthesis of 2,3-diarylbenzofurans via sequential iodocyclization and Pd-catalyzed Suzuki coupling reaction of 2-alkynylanisoles with boronic acids in water is reported. The protocol utilizes water as the solvent and there is no need to isolate the intermediate 3-iodine-2-arylbenzofurans, which exemplifies the ideal of green chemistry. Various 2-alkynylanisoles and boronic acids can participate in the reactions, providing a series of 2,3-diarylbenzofurans for drug discovery in moderate to good yields.

Generalized two-dimensional (2D) Fourier transform infrared correlation spectroscopy was used to investigate the effect of the comonomer compositions on the crystallization behavior of two types of biosynthesized random copolymers, poly(hydroxybutyrate-co-hydroxyhexanoate) and poly(hydroxybutyrate-co-hydroxyvalerate). The carbonyl absorption band around 1730 cm−1 was sensitive to the degree of crystallinity. 2D correlation analysis demonstrated that the 3-hydroxyhexanoate units preferred to remain in the amorphous phase of the semicrystalline poly(hydroxybutyrate-co-hydroxyhexanoate) copolymer, resulting in decreases in the degree of crystallinity and the rate of the crystallization process. The poly(hydroxybutyrate-co-hydroxyvalerate) copolymer maintained a high degree of crystallinity when the 3-hydroxyvalerate fraction was increased from 0 to 25 mol % because of isodimorphism. The crystalline and amorphous absorption bands for the carbonyl bond for this copolymer, therefore, changed simultaneously. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 649–656, 2002; DOI 10.1002/polb.10126

On the basis of the results from Scanning Electron Microscopy (SEM) experiments on 76 samples, we present important evidence associated with the dextral strike-slip movement of the Liaohe Basin, China during the Dongying phase of late Eogene times. We propose that the dextral strike-slip movement of the Liaohe Basin occurred during the Dongying phase of Late Eogene. This post-rift movement reactivated older extensional faults and produced new faults. New studying results indicate that the dextral strike-slip movement is one of major events throughout the complex history of the structural evolution in the Liaohe Basin. It controlled effectively the pattern of the fault systems in the basin. This phase of the movement influenced and controlled oil-gas migration and accumulation in the basin.

The premelting behavior of bacterially synthesized polyester poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), abbreviated as P(HB-co-HHx), was investigated by two-dimensional Fourier-transform infrared (2D FTIR) correlation spectroscopy. The temperature-dependent dynamic spectra were measured over a temperature range of 25–300°C. We focused our study on the thermally induced intensity fluctuations of bands for CO (1700–1760 cm−1), CH (2910–3010 cm−1) and COC groups (1220–1310 cm−1) stretching vibrations. Changes of crystalline conformation due to the thermal perturbation could be detected by the intensity and location variations of those characteristic bands responding to the variations of dipole moments. 2D correlation analysis indicated that the appearance of fully amorphous component did not happen simultaneously with the disappearance of crystalline component, suggesting that there was an intermediate state between ordered crystalline and amorphous states in P(HB-co-HHx). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 934–940, 2001

The characteristics of the general atmospheric circulation during the catastrophic flood period over Yangtze River Valley in 1998 are discussed. There are two patterns of precipitation distribution: the pattern of floodwater over Yangtze and Precipitation more than normal in the whole country, and the pattern of floodwater over Yangtze and precipitation less than normal in its north and south. The 500hPa circulation characteristics of the two patterns are studied. The results show that there are obvious difference of the 500hPa circulation in the northern hemisphere. The establishment of Okhotsk Sea Blocking High is a major factor in causing the floodwater over Yangtze valley and the intensity of South China Sea High is a important factor of forming the pattern of floodwater over Yangtze and precipitation more than normal in the whole country. [

Members belonging to the siderophilin family are iron-binding and iron-transporting proteins, which includes transferrin and lactoferrin. They have only been found in animals previously. If siderophilin could be found in and isolated from a plant, its production and subsequent extensive application could be increased. The present study is the first to report the discovery of a homolog of siderophilin in a plant. In order to purify antifreeze proteins from Ammopiptanthus mongolicus (Maxim.) Cheng f., the authors processed the proteins from the leaves using techniques such as column chromatography using DEAE-Cellu-lose-52, gel filtration via Sephacryl S-100 HR medium, hydrophobic interaction chromatography, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mass spectroscopy was performed on the three proteins purified and the sequence of one of the proteins (containing 32 amino acids) was found to have 97% homology with the corresponding part of one type of human lactoferrin. Moreover, one of the two peptides belongs to an iron-binding domain. So, it is possible that siderophilin also exists in plants and plays a role as an antibacterial and antifungal, among other actions. (Managing editor: Wei WANG)