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Shan-Shan Cui,1 Li-Jun Duan,1 Jun-Feng Li,1 Yong-Zhang Qin,2 Su-Qing Bao,1 Xia Jiang1 1Department of Endocrinology and Metabolism, Tianjin First Central Hospital, Tianjin, People’s Republic of China; 2Department of Endocrinology, First Affiliated Hospital of Gannan Medical University, Ganzhou, People’s Republic of ChinaCorrespondence: Shan-Shan CuiDepartment of Endocrinology and Metabolism, Tianjin First Central Hospital, No. 24 of Fukang Road, Nankai District, Tianjin, People’s Republic of ChinaTel +86 15022353629Email shanshan87@tom.comObjective: This study aims to explore the factors influencing the renal glucose threshold (RTG) in patients with newly diagnosed type 2 diabetes mellitus (T2DM).Methods: A cross-sectional study was conducted on 1009 hospitalized patients with T2DM using stratified random sampling. Blood glucose was monitored using a dynamic blood glucose monitor to obtain the mean blood glucose (MBG), which is used to calculate the RTG. The factors influencing the RTG were then analyzed.Results: The mean RTG in patients with newly diagnosed T2DM was 203.58 ± 55.22 mg/dl. The correlation between the RTG and the various variables was analyzed, and the results demonstrated that the RTG was correlated with the patient’s age (r = − 0.14539, P = 0.0001); MBG (r = − 0.35009, P = 0.0001); renal long neck (r = 0.16762, P = 0.0001); homeostatic model assessment for insulin resistance (r = − 0.38322, P = 0.0001); homeostatic model assessment for beta-cell function (r = − 0.22770, P = 0.0001); and the levels of glycated hemoglobin (HbA1c; r = 0.98994, P = 0.0001), blood urea nitrogen (r = − 0.11093, P = 0.0004), creatinine (r = − 0.26414, P = 0.0001), uric acid (r = − 0.20149, P = 0.0001), total cholesterol (r = 0.13192, P = 0.0001), low-density lipoprotein (r = 0.12466, P = 0.0001), thyroid-stimulating hormone (r = − 0.06346, P = 0.0460), beta-2 microglobulin (r = − 0.08884, P = 0.0056), and 24-hour urine glucose (r = 0.32115, P = 0.0001). Multiple linear stepwise regression analysis revealed that the HbA1c, 24-hour urine glucose, estimated glomerular filtration rate (eGFR), D-dimer, and body mass index (BMI) should be included in the final model, and HbA1c had the greatest impact on the RTG followed in descending order by the 24-hour urine glucose, eGFR, D-dimer, and BMI (P < 0.05).Conclusion: The RTG increases in most patients with newly diagnosed diabetes. The risk factors for the RTG are HbA1c, 24-hour urine glucose, eGFR, D-dimer, and BMI.Keywords: newly diagnosed, type 2 diabetes mellitus, renal glucose threshold, continuous glucose monitoring

A fluorescent light-up ligand for an i-motif structure has been reported in this study. Chelerythrine (CHE) could bind to i-motif and show a significant increase in the fluorescence intensity, while exhibiting weak response towards single-stranded (ssDNA), double-stranded (dsDNA), and G-quadruplexes. This feature makes CHE advantageous in the label-free fluorescence sensing systems.

SO3 in the copper smelting flue gas not only causes serious corrosion in heat exchange and dust collection equipment but also increases the amount of sewage acid (waste acid or polluted acid from copper smelting). In this study, we attempted to reduce the damage by ejecting pyrite into the flue to suppress SO3 formation in the flue. First, the Gibbs free energy for the chemical reactions between the substances was obtained after ejecting pyrite. Subsequently, the thermodynamic study of SO2-O2-H2O-N2-CO2-CO system was performed. Then, a kinetic study on the decomposition and oxidation behaviour of pyrite in the flue system was performed through thermogravimetric experiments. Results show that pyrite decomposition and oxidation in the flue system have a very strong oxygen consumption capacity. The SO3 formation in the copper smelting flue gas is suppressed by the consumption of oxygen in the flue to control the reaction direction of 2SO2 + O2 ⇋ 2SO3 and the partial pressure of SO3.

A series of adjustable long chain branching poly(L-lactide)s (b-PLAs) was prepared by reactive processing of linear PLA using pyromellitic dianhydride (PMDA) and polyfunctional epoxy ether (PFE) as the branching agent and their vascular stents were fabricated via 3D-printing. Fourier-transform infrared (FTIR) spectroscopy and gel permeation chromatography (GPC) results indicated that the chain branching reaction occurs and the average molecular weight increases obviously after the chain branching reaction. Rheological tests on the b-PLAs demonstrated that they are composed of a symmetric- or asymmetric-star, or tree-like chain configuration. The volume fraction of the branching structure of the chains increased from 0.03 to 0.3 with increasing branching agent content. The effects of the branching structure on the melt crystallization behavior of b-PLAs were investigated by means of differential scanning calorimetry (DSC). The isothermal crystallization results showed that the half-time of crystallization (t1/2) of the samples decreased from 16.8 min for linear PLA to 2.3 min when the branching agent content was 2 wt% at 106 °C. Also, as observed from polarized optical microscopy experiments, the nucleation density of the b-PLAs significantly increased with increasing volume fraction of the branching structure because the enrichment of segments around the branching structure facilitated nucleation, thus the b-PLA samples have a higher probability to form a primary nucleus than linear PLA. Moreover, mechanical testing demonstrated that forming the branching structure enabled the effective modification of the mechanical properties of PLA. The microstructures with a smaller spherulite size and higher crystallinity of the b-PLAs improved their tensile strength and modulus from 45.7 MPa and 1.63 GPa to 77.2 MPa and 3.41 GPa, respectively. Furthermore, the radial force performance of the 3D printed b-PLA vascular stents was enhanced from 4.8 to 13.7 N by the branching structure of the chains. The CCK-8 assay results indicated that the osteoblast activity of b-PLA is higher than that of linear PLA, and the scanning electron microscopy (SEM) results also indicated that b-PLA was covered and flattened with a better attachment morphology for the osteoblasts than PLA. Therefore, the b-PLAs with a long chain branching structure could effectively facilitate cell growth, proliferation, and differentiation.

A rapid and efficient methodology for the synthesis of polysubstituted para-quinone methides (p-QMs) from aldehyde and 2,6-di-tert-butylphenol has been achieved in solvent-free and microwave irradiation condition within 33 min. This strategy displays the advantages including high atom economy, good functional group tolerance, and environmentally friendly operation. Keywords: Para-Quinone methides (p-QMs), Green chemistry, Microwave irradiation, Environment friendly synthesis

A highly efficient arylation of para-quinone methides (p-QMs) with N,N-dimethylaniline under solvent free condition has been developed, which proceeded via a para-toluenesulfonic acid (TsOH)-promoted 1,6-conjugated addition pathway. This methodology provided a green and sustainable methodology to construct various novel unsymmetrical triarylmethanes (TAMs) with the advantages of good functional group tolerance, scalability, and regioselectivity.

The purpose of this study was to investigate the effects of metal oxides and smelting dust on the formation of sulfur trioxide during copper, lead, zinc smelting process and flue. Focusing on the effects of SO2 concentration, O2 concentration, and temperature on SO2 oxidation conversion rate under homogeneous test conditions, and under various metal oxide oxidation conditions, further in dust (mainly electric dust removal ash in copper, lead, zinc smelting process), which were studied by single factor experiment test. The results showed that the effect of heterogeneous catalytic oxidation on SO2 conversion rate is much greater than that of pure gas phase oxidation. The addition of five pure metal oxides such as Fe2O3, CuO, Al2O3, ZnO, and CaO obviously promoted the SO2 conversion rate under different conditions. At different temperatures, the ability of metal oxides to promote SO2 conversion is ranked: Fe2O3 &gt, CuO &gt, CaO &gt, ZnO &gt, Al2O3. The catalytic oxidation of copper, lead, and zinc smelting dust to SO2 conversion rate was studied, and the conclusion was drawn that the metal oxides that promoted SO2 conversion rate in copper smelting dust were Fe2O3, Al2O3, ZnO, CaO, and the main substance was Fe2O3, the metal oxides that promoted SO2 conversion in zinc smelting dust were Fe2O3, Al2O3, ZnO, CaO, CuO, and the main substances were Fe2O3 and ZnO, the metal oxides that promoted SO2 conversion rate in lead smelting dust were Fe2O3. Whether metal oxides or copper, zinc, lead smelting dust in the experiment, Fe2O3 displayed the strongest catalytic oxidation capacity.

An efficient chemoenzymatic route has been developed for the synthesis of optically active pregabalin (PGB) from isobutylsuccinonitrile (IBSN). (S)-3-cyano-5-methylhexanoic acid ((S)-CMHA), a criti...

A novel tandem intermolecular ammonium ylide formation/intramolecular Mannich-type [5+1] cyclization reaction of aryl diazoacetates and ortho-aminophenyl imine derivatives was developed. The reaction provides an efficient methodology for direct synthesis of diverse trisubstituted tetrahydroquinoxalines bearing a quaternary stereogenic carbon center in moderate to good yields with excellent diastereoselectivity. This process features high efficiency, mild reaction conditions, and high stereoselectivity.

A novel sulfonylation of para-quinone methides with sodium arylsulfinates has been developed via acetic acid promoted sulfa-Michael addition. This reaction provides an inexpensive and efficient method to synthesize various unsymmetrical diarylmethyl sulfones, displaying the advantages of high atom economy, good functional group tolerance, scalability, and environmentally friendly operation. Derivations of target products are also demonstrated.

Background In recent years, adding nanoparticles to fermentative hydrogen production system has become an effective way to increase the biohydrogen yield, however, the application of green synthesized nanoparticles to hydrogen production system is rarely studied, even to the interpretation of the regulatory mechanism, there are few reports on the regulation of hydrogen production pathway and related gene expression by addition of nanoparticles. Thus, we herein reported the green synthesis of nickel oxide nanoparticles (NiO-NPs) from Eichhornia crassipes (Ec) extract for the first time, and evaluated the regulatory effect of these NPs on fermentative hydrogen production. Results Characterization of the Ec-NiO-NPs revealed their spherical shape, small diameter (9.1 ± 2.6 nm) and high purity. The maximum cumulative hydrogen production and hydrogen yield Y(H2/S) reached 4842.19 ± 23.43 mL/L and 101.45 ± 3.32 mL/gsubstrate, respectively, in the presence of 20 mg/L Ec-NiO-NP, which were 47.29% and 37.78% higher than the control without NPs addition. Evaluation of glucose and xylose utilization efficiency as well as key node metabolites further established the potential of Ec-NiO-NP to improve the reducing sugar utilization and metabolic flux distribution in hydrogen synthesis pathway. Furthermore, addition of 20 mg/L Ec-NiO-NP resulted in enhanced hydrogenase activity with a maximum increase of 623% comparing to the control, and led to changes in the gene expression of both hydrogenase and formate-hydrogen lyase, which play important roles in promoting hydrogen production at different stages of fermentation. Conclusions The results prove that supplementation with green-synthesized Ec-NiO-NP effectively improves fermentative hydrogen production and regulates key node metabolites alteration and functional gene expression. This study provides a cheap and eco-friendly method to enhance fermentative hydrogen production and new insights to reveal the regulatory mechanism underlying NP mediated increases in biohydrogen synthesis.

A highly efficient sulfonylation of para-quinone methides with sulfonyl hydrazines in water has been developed on the basis of the mode involving a tetrabutyl ammonium bromide (TBAB)-promoted sulfa-1,6-conjugated addition pathway. This reaction provides a green and sustainable method to synthesize various unsymmetrical diarylmethyl sulfones, showing good functional group tolerance, scalability, and regioselectivity. Further transformation of the resulting diarylmethyl sulfones provides an efficient route to some functionalized molecules.

We report a new approach to create metal-binding site in a series of metal-organic frameworks (MOFs), where tetratopic carboxylate linker, 4',4'',4''',4''''-methanetetrayltetrabiphenyl-4-carboxylic acid, is partially replaced by a tritopic carboxylate linker, tris(4-carboxybiphenyl)amine, in combination with monotopic linkers, formic acid, trifluoroacetic acid, benzoic acid, isonicotinic acid, 4-chlorobenzoic acid, and 4-nitrobenzoic acid, respectively. The distance between these paired-up linkers can be precisely controlled, ranging from 5.4 to 10.8 A, where a variety of metals, Mg2+ , Al3+ , Cr3+ , Mn2+ , Fe3+ , Co2+ , Ni2+ , Cu2+ , Zn2+ , Ag+ , Cd2+ and Pb2+ , can be placed in. The distribution of these metal-binding sites across a single crystal is visualized by 3D tomography of laser scanning confocal microscopy with a resolution of 10 nm. The binding affinity between the metal and its binding-site in MOF can be varied in a large range (observed binding constants, Kobs from 1.56×102 to 1.70×104 L mol-1 ), in aqueous solution. The fluorescence of these crystals can be used to detect biomarkers, such as cysteine, homocysteine and glutathione, with ultrahigh sensitivity and without the interference of urine, through the dissociation of metal ions from their binding sites.

To address the problem of food security, China produced potatoes as a staple food in 2015.However, there are increasing problems with continuous cropping production methods, potato continuous cropping has been inevitable.So it is necessary to research under the different potato continuous cropping ways, potato rhizosphere soil nutrients and enzyme activities which can direct potato fertilizer and ease potato continuous cropping obstacle. A two-growing season investigation was carried out during the spring and autumn of 2014 and 2015 to determine the different ways of potato continuous cropping on the overall growth of potatoes, soil nutrients, and enzyme activities. During continuous cropping nitrogen (N) content of rhizosphere soil was reduced; available potassium (Kav) was significantly reduced(p≤5%), especially in spring and autumn continuous cropping; and total phosphorus (Ptot) was reduced during the growth stage. However, the total potassium (Ktot), available phosphorus(Pav), and organic carbon (Ctot) increased before they decreased. For rhizosphere soil enzyme activities, urease initially increased and then decreased, and was lower in continuous cropping than multiple continuous cropping; in spring of 2015, invertase was the highest with continuous cropping. Catalase and polyphenol oxidase decreased initially before increasing. Continuous cropping in spring and autumn consumed more nutrients, especially potassium (K) than in spring. Therefore, potatoes planted in both spring and autumn enhanced the problems of continuous cropping. However, multiple continuous cropping that eased rhizosphere soil nutrient absorption and effectively improves soil nutrients and enzyme activities could provide an effective method for managing the negative impacts associated with continuous cropping.

C23H33O4P, monoclinic, P21/c (no. 14), a = 10.4629(3) Å, b = 11.4909(5) Å, c = 19.3341(9) Å, β = 98.201(4)°, V = 2300.73(16) Å3, Z = 4, R gt(F) = 0.0550, wR ref(F 2) = 0.1109, T = 298 K.

C27H32O3S, triclinic, P1̄, a = 12.2441(2) Å, b = 14.9350(2) Å, c = 15.2081(3) Å, α = 73.6710(16)°, β = 70.1267(17)°, γ = 70.7828(15)°, V = 2424.41(8) Å3, Z = 4, R gt(F) = 0.0442, wR ref(F 2) = 0.1319, T = 297.1(2) K.

The occurrence, distribution and bioaccumulation of six endocrine disrupting compounds (EDCs) were investigated in water, sediment and biota samples from Luoma Lake, a shallow Chinese freshwater lake. Total concentrations of ∑phenolic EDCs were much higher than ∑estrogens EDCs in both waters and sediments. There were not obvious differences on the concentrations of target compounds [except nonylphenol (NP)] in upstream, lake and downstream locations, these may be suggested that they were mainly affected by non-point discharges in this area. However, the high concentration of NP in water may be associated with the discharge of rural domestic wastewater without thorough treatment. Furthermore, concentrations of NP were about 2–3 order magnitude higher than those of OP in both water and sediment compartments. Relatively higher bioaccumulation factors (BAF) were obtained for DES and EE2. Ecological risk assessment revealed greater risk of NP in surface water, which may pose a serious threat to aquatic ecosystems. The estrogen equivalent concentration (EEQ) of male were higher than those in female, and occurred in the order of city >rural-urban>countryside.

BACKGROUND Acid-sensing ion channels (ASICs) are ligand-gated cation channels activated by extracellular protons. However, the role of ASICs in kidney diseases remains uncertain. This study investigated ASICs expression in kidney tissues and their role in the development of Henoch-Schönlein purpura nephritis (HSPN). MATERIAL AND METHODS The expression of ASIC subunits was examined by immunochemical techniques in the kidney tissue from HSPN patients. Acid-induced ASICs expression in cultured renal tubular epithelial cells was determined by quantitative RT-PCR analysis. The expression of K7 and K18 protein in renal tubular epithelial cells was used to evaluate acid-induced cell injury. In addition, we observed the effect of blocking ASICs on acid-induced cell injury to assess the role of ASICs in renal tubular epithelial cell injury. RESULTS The results showed that ASIC1, ASIC2, and ASIC3 proteins were obviously expressed in renal tubular cells from HSPN patients. ASIC1 expression and 24-h urine protein level were higher in the pathological grade ISKD III group than in the ISKD II group. ASIC1, ASIC2, and ASIC3 mRNA, and K7 and K18 protein expression in cultured renal tubular epithelial cells were increased when exposed to pH 6.5. K7 and K18 protein expression was closely related to ASIC1 expression, and ASICs blockers reduced K7 and K18 protein expression in tubular epithelial cells. CONCLUSIONS These findings suggest ASICs are most highly expressed in renal tubular cells of HSPN patients, which is closely related to renal tubular injury. ASICs might be involved in the development of HSPN.

Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides (SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60°C, solid-liquid ratio 1:6 g mL−1, duration 5 h, and alkali (NaOH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant.

C28H35NO3S, triclinic, P1̄ (no. 2), a = 10.3965(4) Å, b = 10.7525(5) Å, c = 12.2772(6) Å, α = 86.651(4)°, β = 86.653(4)°, γ = 75.323(4)°, V = 1324.05(11) Å3, Z = 2, R gt(F) = 0.0472, wR ref(F 2) = 0.1298, T = 291 K.

Protein engineering is a powerful tool for improving the properties of enzymes. However, large changes in enzyme properties are still challenging for traditional evolution strategies because they usually require multiple amino acid substitutions. In this study, a feasible evolution approach by a combination of fragment swapping and semi-rational design was developed for the engineering of nitrilase. A chimera BaNIT harboring 12 amino acid substitutions was obtained using nitrilase from Arabis alpine (AaNIT) and Brassica rapa (BrNIT) as parent enzymes, which exhibited higher enantioselectivity and activity toward isobutylsuccinonitrile for the biosynthesis of pregabalin precursor. The semi-rational design was executed on BaNIT to further generate variant BaNIT/L223Q/H263D/Q279E with the concurrent improvement of activity, enantioselectivity, and solubility. The robust nitrilase displayed a 5.4-fold increase in whole-cell activity and the enantiomeric ratio (E) increased from 180 to higher than 300. Molecular dynamics simulation and molecular docking demonstrated that the substitution of residues on the A and C surface contributed to the conformation alteration of nitrilase, leading to the simultaneous enhancement of enzyme properties. The results obtained not only successfully engineered the nitrilase with great industrial potential for the production of pregabalin precursor, but also provided a new perspective for the development of novel industrially important enzymes.

Nitrilase-mediated hydrolysis of isobutylsuccinonitrile (IBSN) is a highly attractive approach for (S)-3-cyano-5-methylhexanoic acid ((S)-CMHA), the critical chiral intermediate of pregabalin. In this study, a robust nitrilase from Arabis alpina (AaNIT) was screened and engineered. The N258D mutant was obtained with high catalytic activity and excellent enantioselectivity (E > 300) towards IBSN at a high substrate concentration of 100 g L-1. Byproduct (S)-3-cyano-5-methyl hexanoic amide ((S)-CMHM) was detected and identified for the first time during the catalytic process. By employing a feasible one-pot bienzymatic cascade of mutant N258D and amidase from Pantoea sp. (Pa-Ami) expressed separately in recombinant Escherichia coli cells, the byproduct (S)-CMHM was eliminated and (S)-CMHA was obtained with a conversion of 45.0% and eep of 99.3%. These results provided the novel plant-derived nitrilase as a promising biocatalyst for (S)-CMHA biosynthesis and demonstrated the feasibility of one-pot bienzymatic cascade reaction for large-scale production of the pregabalin precursor.

Due to the extensive use in consumer products, the bisphenols (BPs) pollution in the environments has aggravated and people are frequently exposed to BPs. In this research, four BPs, i.e., bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS) and bisphenol AF (BPAF), were determined in urine samples collected from Gaochun District preschool-age children and the concentrations, distribution profiles, potential sources and cumulative risk assessment of the target compounds were studied. Total concentrations of 4 BPs ranged from 2 to 3113.1 ng/L, with the average concentration of 648.6 ng/L. BPA was the predominant congener (accounting for 94%), followed by BPS. Correlation analysis indicated a negative relationship between BPA and BPAF (R = -0.273, p 0.05). The estimated daily intakes suggested that young females were more sensitive to BPs. Moreover, the cumulative risk for hazard quotient (HQ) of BPA has been evaluated and the results showed that no high risk had occurred. It provided basic information on the occurrence and human exposure to urinary BPs of preschool aged children from Gaochun District.

Taking the bisphenol A epoxy resin system as the research object, the thermal curing and microwave curing experiments were carried out. The relationship between the curing degree and the hardness of the product after thermal curing and microwave curing was analyzed. The thermally cured product and microwave cured product were tested for tensile properties and infrared spectroscopy respectively. The results show that there is a positive correlation between the degree of curing of the product and the surface hardness. Compared with thermal curing, microwave curing can save 50% of the time, and the microwave cured product does not generate a new structure. The tensile strength of the microwave cured product is about that of thermal curing. 88% of the tensile strength of the product.

Organophosphate esters (OPEs) are ubiquitous in the environment and pose a potential threat to ecosystem and human health. This study investigated the concentrations, distributions and risk of 12 OPEs in surface water and sediment from Luoma Lake, Fangting River and Yi River. Solid-phase extraction (SPE) method were used to extract OPEs from water samples, ultrasonic process and SPE method were used to extract OPEs from sediment samples, and the extracts were finally analyzed using the HPLC-MS/MS. The results revealed that the median and maximum concentrations of ΣOPEs were 73.9 and 1066 ng/L in surface water, and were 28.7 and 35.9 ng/g in sediment, respectively. Tris(2-chloroethyl) phosphate (TCEP) and trimethyl phosphate (TMP) were the most abundant OPEs in the surface water with median concentrations of 24.3 and 16.4 ng/L in Luoma Lake, respectively. Triethyl phosphate (TEP) was the most abundant OPE in the sediment with a median concentrations of 28.9 ng/g. However, tricresyl phosphate (TCrP) and ethylhexyl diphenyl phosphate (EHDPP) predominantly contributed to the ecological risk with respective median risk quotients 0.07 and 0.01 for surface water in Luoma Lake. TEP and TCrP were the most significant contributors to the ecological risk with respective median risk quotients of 6.4 × 10−4 and 5.6 × 10−4 for sediment. It was also found that inflowing Fangting River could be the major pollution source to Luoma Lake. The no-cancer and carcinogenic risks of OPEs were lower than the theoretical threshold of risk. The study found that the ecological and human health risks due to the exposure to OPEs were currently acceptable. In other words, the Luoma Lake was relatively safer to use as a drinking water source in urban areas in the context of OPEs pollution.

There have been few studies of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in environmental water because of the large volume of water required for PCDD/Fs analysis. Water quality directly affects aquatic organisms, and little is known about how PCDD/Fs are transported in aquatic environments. PCDD/Fs were analyzed in eight water samples from Dongting Lake, China, which was contaminated with PCDD/Fs because of sodium pentachlorophenate use between the 1960s and the 1980s. The total PCDD/F concentrations in the samples were 36-345 pg L(-1), and the mean was 191 pg L(-1). Octachlorodibenzo-p-dioxin was the most abundant PCDD/F congener in every sample, contributing 67-95% of the total 2,3,7,8-chlorinated PCDD/F concentrations. The toxic equivalent (WHO-TEQ) concentrations in the samples were 0.17-0.37 pg L(-1), and the mean was 0.28 pg L(-1), which is higher than the Canadian environmental quality guideline (0.038 pg L(-1) WHO-TEQ for freshwater) and the United States Environmental Protection Agency water quality criterion (0.014 pg L(-1) WHO-TEQ). PCDD/Fs were also determined in six fish species collected from Dongting Lake, to assess the concentrations, accumulation patterns, and potential for toxic effects. The total 2,3,7,8-chlorinated PCDD/F concentrations in the fish samples were 2.2-17.9 pg g(-1) (wet weight), and the dominant congeners were octachlorodibenzo-p-dioxin, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 1,2,3,4,7,8-hexachlorodibenzo-p-dioxin, and 2,3,4,7,8-pentachlorodibenzofuran. The PCDD/F WHO-TEQs were 0.10-0.92 ww (3.3-65.3l w) pg g(-1) in different species of fish. PCDD/F congener patterns in fish may be affected by food chain biomagnification and the lipid content of the species.

Few studies have been conducted to investigate the polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in freshwater since the volume of water needed for dioxin analysis is large. In this study, 19 water samples from the middle reaches of the Yangtze River were analysed for the levels of PCDD/Fs and dioxin-like PCBs (dl-PCBs). The results showed that the concentration ranges of PCDD/Fs and dl-PCBs were 0.6-8.5 and 2.0-15.8 pg/L, respectively, which were relatively low compared with those reported in the literature. The WHO-TEQ concentration range of dioxins was 0.002-0.040 pg/L. The PCA results indicated that the main sources of PCDD/Fs may be the applications of pentachlorophenol or sodium pentachlorophenate and domestic wood and coal burning. For dl-PCBs, domestic wood burning and coal burning were the main sources.

C21H20N2O2S, monoclinic, P21/c (no. 14), a = 19.436(3) Å, b = 6.1396(6) Å, c = 16.362(3) Å, β = 108.100(16)°, V = 1855.8(5) Å3, Z = 4, R gt(F) = 0.0502, wR ref(F 2) = 0.1224, T = 100 K.

A method was developed for the determination of five categories of 40 antibiotics in surface water by using solid-phase extraction-high performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS). The water samples were enriched and cleaned-up by filtration and with SPE cartridges. All antibiotics were separated by gradient elution with the mobile phase of 0.2% (v/v) formic acid aqueous solution and acetonitrile, and then analyzed with an electrospray ionization source in the positive ion and multiple reaction monitoring (MRM) modes. The results showed that the 40 antibiotics achieved great linearity in the range of 1-200 μg/L, and the average recoveries ranged from 41.3% to 112.6%. Using the developed method, thirteen antibiotics were identified in surface water from Nanjing section of the Yangtze River. The total antibiotic contents in the real samples ranged from 13.4 ng/L to 780.5 ng/L. The established method is efficient, sensitive and reliable, and is suitable for the determination of different antibiotics in real water samples.

Supercritical carbon dioxide (scCO2) processing has been proven as a method for preparing polymer/montmorillonite (MMT) nanocomposites with improved platelet dispersion. The influence of scCO2 processing on the shape and size of the MMT tactoid/platelet, which is of great importance to the final platelet dispersion in the polymer matrix, is scarcely reported in the literature. In the present study, the pristine MMT was first surface modified with 3-glycidoxypropyltrimethoxysilane (the grafted MMT is labeled as GMMT), and then intercalated using three kinds of intercalating agents, myristyltrimethyl-ammonium bromide (MTAB), tetradecyltrihexylphosphonium chloride (TDTHP), and ethoxyltriphenyl-phosphonium chloride (ETPC), in water or scCO2, to study the effect of intercalating agent type and intercalation method on the morphology and thermal properties of GMMT, as a part of a program devoted to the synthesis of polymer/MMT nanocomposites. The structure of intercalated GMMT was characterized by thermogravimetric analysis, X-ray powder diffraction, and scanning electron microscopy (SEM). The optimum intercalation conditions in scCO2 were established by trying a range of reaction times and pressures. The structures of intercalated GMMT obtained under optimum scCO2 conditions and water were compared. The basal spacing of GMMT intercalated in scCO2 was almost the same as that in water, and both were obviously larger than that of GMMT. The GMMT exhibited a compact spherical morphology (examined using SEM), and the surface structures (including surface morphology, surface roughness, and surface compactness) of samples intercalated in water became ‘less compact’ and the degree of the ‘compactness’ of samples intercalated in scCO2 decreased further. Whether in water or scCO2, samples intercalated with TDTHP exhibited a larger basal spacing and the extent of disorder increased compared to that for samples intercalated with MTAB. The pristine MMT was also intercalated for comparison and silane grafting was proven to contribute to the increased basal spacing and ‘less compact’ surface structure.

Poly(ether ether ketone) with pendent sulfonimide groups (B-SPEEK) was prepared from poly(ether ether ketone), sulfuric acid, thionyl chloride, para-toluene sulfonate, and pyridine. The prepared B-SPEEK was characterized by Fourier transform infrared spectroscopy, 1H-NMR, and thermogravimetric analysis. The swelling of the gels was examined in N,N-dimethylacetamide (DMAC), N,N-dimethylformamide (DMF), 1-methyl-2-pyrrolidinone (NMP), dimethyl sulfoxide (DMSO), and a DMSO/water mixture. The gel showed extremely high swelling in DMSO, DMF, DMAC, and NMP. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1058-1063, 2013

To improve the industrial utilization of corn soaking water, the yeast protein powder was produced by microwave-assisted foam drying. Firstly, preparation experiments were carried out, which included the foaming characteristic experiments of fermentation broth and that about the effects of carbon and nitrogen ratio on solid content in the fermentation broth. Secondly, the drying characteristics experiment of corn soaking water was studied, which selected the microwave power, material amount and thickness as the influencing factors for the single experiment. The results showed that the final moisture content (d.b.) and drying rate were significantly affected by those factors.

The one of the important reason which lead to power line dropped is interface aging. According to the core fracture of composite insulator on the 500kV power line of CSPG and the temperature abnormal rise of composite insulators which number are 25, 38, and 42 on No. 5123 tower XuYang power line of Shanghai power company of SGCC, these composite insulators had been done test about each appearance. The results of test show that the hydrophobicity is well and the material of silicon shed isn't aging. But there are some humps on the surface of housing and erosion on the interface between whole housing and core of composite insulators. The penetrant (1%fushine) appear on the interface between housing and core. The erosion had extended from high voltage to the middle part of composite insulator. One of the reasons about erosion on the interface between Housing and core of composite insulators is mold releasing agent seeping from core. The crack between housing and core has been made by the mold releasing agent and the partial discharge has appeared. The water which were absorbed on the production of core has taken part in electrochemical reaction lead to erosion.

During the last decade, there have been many exploration achievements in the Tibetan Gangdese metallogenic belt. The Sharang area of the Tibetan region is covered by a low-temperature mineralized alterable clay that is considered to be a low-grade ore. Although small intervals of rich molybdenum (Mo) mineralization have been discovered, the ore deposit scale is limited and the condition of deep ore is still unknown. To explore these deeper targets, a modified large-loop TEM system was used in the Sharang area. The TEM receiver configuration is redesigned and the late-time resistivity equation of large-loop TEM has also been defined. During data processing, two regions with low resistivity anomalies were discovered. The interpreted results indicate that the main ore deposit is buried 200 m beneath the surface, and extends 600 m vertically. The total anomalous area associated with the ore deposit is estimated at 3.77 km2. The interpretation results are consistent with drilling data acquired after the geophysical survey. The results show that it is the first ultra-large porphyry molybdenum deposit that has been found in Tibet.

Whole cells of Rhodotorula glutinis reduced N-methyl-3-oxo-3-(thiophen-2-yl) propanamide at 30 g/l to (S)-N-methyl-3-hydroxy-3-(2-thienyl) propionamide, an intermediate in the production of (S)-duloxetine, a blockbuster antidepressant drug, in 48 h. The reaction had excellent enantioselectivity (single enantiomer, >99.5% enantiomeric excess [ee]) with a >95% conversion.

以MnSO 4 H 2 O和(NH 4 ) 2 S 2 O 8 为原料通过控制水热反应条件合成了纯的四方相β-MnO 2 纳米氧化物, 进一步通过低温固相法制备了立方相Li 4 Mn 5 O 12 , 经酸浸脱锂后得到对Li + 具有特殊选择性的MnO 2 离子筛. 用XRD、HRTEM、SAED、吸附等温线、吸附动力学及共存金属离子的分配系数等手段对产物的晶相结构和Li+选择性吸附性能进行了研究. HRTEM和SAED图像表明氧化物MnO 2 、前驱体Li 4 Mn 5 O 12 和离子筛MnO 2 均为低维纳米棒. 离子筛的最大吸附量达到6.6 mmol/g, 且当Li + 初始浓度仅为5.0 mmol/L时, 离子筛的吸附量即可达到约5.0 mmol/g, 这对于在海水或锂离子浓度极低的盐湖卤水提锂具有重要的实用意义.

Chiral sulfoxides were prepared in excellent enantio-selectivitythrough α′,β-elimination of the TERT-butyl substituted sulf-oxoniumylide intermediates in situ generated from diazoacetates and ( R)- N- TERT-butylsulfinyl aldimines in the presenceof a copper(I) catalyst.

Using temperature distribution as an external parameter to change symmetry and measuring frequency spectrum of acoustic resonances in aluminium blocks, we investigate the statistics and dynamics of energy levels in the chaotic billiards. To extract the resonances accurately and eliminate the influence of noise, a filter-diagonalization method for harmonic inversion is used to overcome low resolution of conventional fast Fourier transform method for low quantity factor resonance systems. We present an improved and feasible simulation method to study chaotic characteristic of quantum systems experimentally.

OBJECTIVE Increasing of adhesion between leukemia cells and endothelial cells during all-trans retinoic acid (ATRA) treatment plays an important role in retinoic acid syndrome. This work observed the effects of tripterine on this ATRA-caused increasing in adhesion. METHODS The effects of tripterine on ATRA-induced expressions of adhesive molecules in acute promyelocytic leukemia cell line NB4 and human umbilical vascular endothelial cells (HUVEC) were detected by flow cytometry. The effects of tripterine on adhesion between ATRA-treated NB4 and HUVEC were determined by adhesive assays. RESULTS ATRA caused remarkable elevation of intercellular adhesion molecule-1 (ICAM-1) in NB4 cells, which could be significantly reduced by tripterine (P

The kinetics behavior of methane hydrate formation in the presence of tetrahydrofuran (THF) as promoter was studied. A set of experimental equipment was designed and constructed. A series of kinetics data for the formation of methane hydrate in the presence of THF were measured with the isochoric method. The influences of temperature, pressure and liquid flow rate on the methane consumption rate were studied respectively. Based on the Chen-Guo hydrate formation mechanism, a kinetics model for the formation of methane hydrate in the presence of THF by using the dimensionless Gibbs free energy difference of quasi-chemical reaction of basic hydrate formation, — δG/RT as the driving force was proposed. The model was used to calculate the rate of methane consumption and it was shown that the calculated results were in good agreement with the experimental results.