Synthesis of azo-linked covalent organic polymers for pipette tip solid-phase extraction of sedative residues from animal tissues samples.

Azo-linked covalent organic polymers (ACOPs) were synthesized by a simple azo reaction, with 2,2'-bis(trifluoromethyl)benzidine and 1,3,5-trihydroxybenzene as the monomers. The preparation process was mild, green, and environmental-friendly, avoiding the use of high temperature, metal catalysis, and harmful organic reagent. The obtained ACOPs were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and Brunauer-Emmett-Teller.

Pipette-tip solid-phase extraction using cetyltrimethylammonium bromide enhanced molybdenum disulfide nanosheets as an efficient adsorbent for the extraction of sulfonamides in environmental water samples.

Surfactant cetyltrimethylammonium bromide enhanced molybdenum disulfide was used as an adsorbent in pipette-tip solid-phase extraction for the pretreatment of sulfonamides in environmental water samples. The factors affecting the extraction recoveries of the analytes, including the sample pH value, amount of sorbent, type and volume of eluent solution, and salt concentration were optimized. This pipette-tip solid-phase extraction method demonstrated good linearity (0.

Prevalence and Antimicrobial Resistance of in Pork, Chicken, and Duck from Retail Markets of China.

is one of the most important foodborne pathogens associated with animal and human diseases. In this study, 672 samples of fresh meat (pork, 347; chicken, 196; and duck, 129) were collected from retail markets in different provinces of China from 2010 to 2014. We identified 10 different serotypes among 80 isolates, whereas 12 isolates were nonmotile precluding conventional identification of complete serotype.

[Seasonal and Spatial Variations of Microcystins and Their Relationships with Physiochemical and Biological Factors in Poyang Lake].

Poyang Lake is the largest freshwater lake in China and an important drinking water source for Jiangxi Province. Since the year 2000, toxic cyanobacteria have been observed frequently in Poyang Lake. In this study, water samples were collected in the lake quarterly (April 2012, August 2012, October 2012, and January 2013) to examine the spatial and seasonal variations in the concentrations of microcystins (MCs; MC-RR, -YR, and -LR) and their relationships with physiochemical and biological factors.

Chitosan-poly(m-phenylenediamine)@Fe₃O₄ nanocomposite for magnetic solid-phase extraction of polychlorinated biphenyls from water samples.

A extraction medium based on chitosan-poly(m-phenylenediamine) (CS-PPD) @Fe3O4 nanocomposite was synthesized by chemical polymerization of m-phenylenediamine in the presence of chitosan coated magnetic nanocomposite, and for the first time, used as the sorbent for the magnetic solid-phase extraction (MSPE) of seven polychlorinated biphenyls (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, and PCB180) at trace levels in water samples. Gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was used for PCBs quantification and detection. Several factors related to MSPE efficiencies, such as type and amount of sorbent, extraction time, sample pH, and desorption conditions were investigated.

Simultaneous determination of Se, trace elements and major elements in Se-rich rice by dynamic reaction cell inductively coupled plasma mass spectrometry (DRC-ICP-MS) after microwave digestion.

A quick and accurate method was devised to determine Se, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr and Zn in Se-rich rice samples by microwave digestion and inductively coupled plasma-mass spectrometry (ICP-MS). Spectral interferences on Se were eliminated using methane as a reaction gas in the dynamic reaction cell (DRC). Rhodium was used as an internal standard to compensate for sample matrix effects.

Metal concentrations in various fish organs of different fish species from Poyang Lake, China.

Concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the muscle of eleven fish species (bighead carp, bream, catfish, carp, crucian, Culter alburnus, grass carp, mandarin fish, white semiknife carp, silver carp, and yellow catfish) from Poyang Lake were analysed using inductive coupling plasma mass spectrometry. Metal levels in other organs (e.g.

Ultrasound-assisted emulsification-microextraction for the sensitive determination of ethyl carbamate in alcoholic beverages.

A method based on ultrasound-assisted emulsification-microextraction (USAEME) was proposed in this contribution for the determination of ethyl carbamate (EC) in alcoholic beverages using gas chromatography coupled to triple quadrupole mass spectrometry. To achieve the determination of EC in alcoholic beverages, the influences on the extraction efficiency of type and volume of extraction solvent, temperature, ionic strength, alcohol content, and extraction time were studied, once the extraction solvent had been selected. The optimized conditions were 200.

Applicability of accelerated solvent extraction for synthetic colorants analysis in meat products with ultrahigh performance liquid chromatography-photodiode array detection.

Accelerated solvent extraction (ASE) coupled with ultrahigh performance liquid chromatography (UHPLC) with photodiode array detection (PDA) has been used for the quantitative determination of synthetic colorants in meat products. Samples were extracted with ethanol-water-ammonia with a ratio of 75:24:1 (v/v/v) using ASE instrument at 85°C. As a result, all the colorants in meat products were separated using an optimized gradient elution within 3.

[Analysis of heading time genotype for a rice photoperiod and thermo--sensitive male sterile line PeiAi64S].

PeiAi64S, a photoperiod and thermo-sensitive genic male sterile, has been wildly applied to hybrid rice seed production in China, but its photoperiod-sensitivity gene for heading date in this sterile line was still unknown. This definitely limited the further use of this sterile line in breeding practice and re-production of hybrid seeds. To solve this problem, using heading time nearly isogenic lines EGO - EG7, ER - LR, T65 - T65m and six heading date QTL-isogenic lines, NIL (Hd1) - NIL (Hd6) with the genes of Nipponbare but Hd1 - Hd6 genes from Kasalath respectively, we performed a genetic analysis of PeiAi64S with special reference to photoperiod-sensitivity loci, in natural long days at Nanjing (32 degrees N) where the average day-length is about 14 h and in natural short days at Linshui county, Hainan province(18 degrees 29'N), where the average day-length is about 11.

[Analysis of photoperiod-sensitivity genes in Minghui63, an restorer line of indica rice(Oryza sativa L.)].

Hybrid rice is very important in agriculture production in China. Its selecting property makes it significant to study the genetic performance of F1's date to heading (DH). Minghui63, an indica rice restorer line, has been widdly applied to hybrid rice seed production in China, but the photoperiod-sensitivity gene of heading date in this restorer line is still unknown.