180 results match your criteria: "Beijing Center For Physical and Chemical Analysis[Affiliation]"

Eight polyphenols were separated from grape seed by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent system composed of 1-butanol-ethyl-water (1:14:15, v/v/v) and -hexane-ethyl-water (1:10:10, v/v/v). The upper and lower phases were used as the stationary and mobile phases, respectively.

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Effective adsorption of diclofenac sodium from neutral aqueous solution by low-cost lignite activated cokes.

J Hazard Mater

February 2020

Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Beijing Advanced Innovation Center For Future Urban Design, Beijing 100044, China. Electronic address:

Activated cokes have attracted great interest inwater treatment to remove organic pollutants due to their low cost and specific textural properties. In this study, adsorptive removal of diclofenac sodium (DCF) from neutral aqueous solution by available lignite activated cokes (LACs) was reported for the first time. Diclofenac sodium could be quickly removed from aqueous solution by LAC-2, with the maximum Langmuir adsorption capacity q of 224 mg/g at pH 6.

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A pyridine-Fe gel with an ultralow-loading Pt derivative as ORR catalyst in microbial fuel cells with long-term stability and high output voltage.

Bioelectrochemistry

February 2020

Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun North First Street 2, Beijing 100190, China. Electronic address:

A low-cost and high-efficiency oxygen reduction reaction (ORR) catalyst was fabricated using a pyridine-Fe gel with ultralow-loading of Pt nanoparticles and subsequently applied to air-cathode microbial fuel cells (MFCs). This novel catalyst (N/Fe/C-Pt) exhibited excellent electrocatalytic activity with a positive onset potential of 0.19 V (vs Ag/AgCl) and half-wave potential of 0.

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Six new compounds, including a new compound with an unusual 2, 4, 6-cycloheptatrien ketone skeleton (1), two new diphenylpropanoid ethers (2, 3), a new protostane-type triterpenoid (4), two new norsesquiterpene (5a, 5b), and two new natural products (6, 7), together with eleven known compounds (8-18) were isolated from the aqueous extract of Alismatis Rhizoma (AR). Their structures were elucidated by a combination of 1D and 2D NMR (H and C NMR, COSY, HSQC, HMBC, and NOESY), HRESIMS spectroscopic data, experimental and calculated electronic circular dichroism (ECD) spectra. Some of the compounds were evaluated for their inhibitory effects on nitric oxide (NO) production in LPS-induced RAW 264.

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Identifying the key chemical compounds and source contributions in ambient particles associated with the burden of cardiopulmonary disease is important to develop cost-effective air pollution mitigating strategies that maximize the protection of public health. To help address this need, we examined 109 daily ambient fine particulate matter samples (PM) that were collected in Beijing in one year. The samples were analyzed for chemical composition including organic and elemental carbons, metals, ions, as well as organic molecular markers.

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Rapid detection of trace Salmonella in milk and chicken by immunomagnetic separation in combination with a chemiluminescence microparticle immunoassay.

Anal Bioanal Chem

September 2019

Beijing Engineering Research Center of Food Safety Analysis, Beijing Engineering Technology Research Centre of Gene Sequencing and Gene Function Analysis, Beijing Center for Physical and Chemical Analysis, Beijing, 100089, China.

Rapid detection of trace Salmonella is urgently needed to ensure food safety. We present an innovative pretreatment strategy, based on a two-step enrichment culture and immunomagnetic separation, combined with a chemiluminescence microparticle immunoassay to detect at least one proliferative Salmonella cell in 25 mL (25 g) food. The capture performance of immunomagnetic beads (IMBs) of sizes for Salmonella was investigated, and the IMBs of size 2.

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Effect of microwave irradiation-retrogradation treatment on the digestive and physicochemical properties of starches with different crystallinity.

Food Chem

November 2019

Department of Food Science and Engineering, College of Biological Sciences and Technology, Beijing Key Laboratory of Forest Food Process and Safety, Beijing Forestry University, Beijing 100083, China. Electronic address:

The effect of microwave irradiation-retrogradation (MIR) treatment on the physicochemical properties and in vitro digestibility of corn starch (A-type crystallinity), potato starch (B-type) and chestnut starch (C-type) were evaluated. After MIR treatment, the amount of resistant starch (RS) increased and rapid digestible starch (RDS) decreased along with the retrogradation time in all three starches. The degree of retrogradation (DR) of starch was significantly positive correlated with amylose and RS content.

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Non-starch constituents influence the in vitro digestibility of naked oat (Avena nuda L.) starch.

Food Chem

November 2019

Department of Food Science and Engineering, College of Biological Sciences and Technology, Beijing Key Laboratory of Forest Food Process and Safety, Beijing Forestry University, Beijing 100083, China. Electronic address:

The present study investigated the effects of proteins, lipids and β-glucan in naked oat flour (NOF) on the in vitro digestibility of starch. The content of rapidly digested starch (RDS) increased, and the content of resistant starch (RS) decreased in NOF after removing the non-starch constituents. The estimated glycemic index (eGI) of starch in NOF increased after the removal of the non-starch constituents, with a decreasing order of naked oat starch (NOS) > de-β-glucan flour > de-proteins flour > de-lipids flour > NOF.

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Concentrations of migrated mineral oil/polyolefin oligomeric saturated hydrocarbons (MOSH/POSH) in Chinese commercial milk powder products.

Food Addit Contam Part A Chem Anal Control Expo Risk Assess

August 2019

b Beijing Center for Physical and Chemical Analysis, Beijing Food Safety Analysis and Testing Engineering Research Center, Beijing Academy of Science and Technology , Beijing , China.

Mineral oil contaminants migrated from food contact materials have raised much concern in the past few decades. However, survey data of the occurrence of mineral oils in foods are only available for a limited variety of foods, which do not include the contaminants in Chinese milk powders. Thus, to conduct an analysis of mineral oils migrated into milk powder products from different packaging materials, 50 Chinese commercial samples (including 38 infant formulas), which were packaged in metal cans, paper containers, paper boxes and aluminium foil-plastic bags, were analysed.

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Regioselectively substituted cellulose mixed esters synthesized by two-steps route to understand chiral recognition mechanism and fabricate high-performance chiral stationary phases.

Anal Chim Acta

September 2019

Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing, 100190, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address:

It is challenging to design and fabricate new and high-performance cellulose-based chiral stationary phases (CSPs), due to the indistinct chiral recognition mechanism and the inherent difficulty to control the structure of cellulose derivatives. Herein, taking advantage of the high regioselective benzoylation of cellulose in 1-allyl-3-methylimidazolium chloride, a series of regioselectively substituted cellulose mixed esters, cellulose 6-benzoate-2,3-phenylcarbamate, are directly obtained by a facile two-steps route without protecting and deprotecting process. The resultant cellulose mixed esters exhibit high chiral recognition capability.

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Rapid screening of mineral oil aromatic hydrocarbons (MOAH) in grains by fluorescence spectroscopy.

Food Chem

October 2019

Beijing Center for Physical and Chemical Analysis, Beijing Food Safety Analysis and Testing Engineering Research Center, Beijing Academy of Science and Technology, Beijing 100089, China. Electronic address:

On-line high-performance liquid chromatography coupled with gas chromatography with flame ionization detector (LC-GC) has become an important technique for the determination of mineral oil aromatic hydrocarbons (MOAH) in foods. However, the analysis is complicated and time-consuming. The present study aimed to develop a fluorescence spectrophotometry approach for the fast screening of MOAH in grains.

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Influence of amylose on the pasting and gel texture properties of chestnut starch during thermal processing.

Food Chem

October 2019

Department of Food Science and Engineering, College of Biological Sciences and Technology, Beijing Key Laboratory of Forest Food Process and Safety, Beijing Forestry University, Beijing 100083, China. Electronic address:

The quality of starchy foods is highly correlated with their amylose content. After boiling or roasting, the amylose content in cooked chestnut starch decreased to 16.6-26.

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Air pollution during the winter period and respiratory tract microbial imbalance in a healthy young population in Northeastern China.

Environ Pollut

March 2019

Key Laboratory of Environmental Pollution and Microecology of Liaoning Province, Shenyang Medical College, No.146, North Huanghe Street, Yuhong District, Shenyang, Liaoning, 110034, China. Electronic address:

In order to investigate the relationship between air pollution and the respiratory tract microbiota, 114 healthy volunteers aged 18-21 years were selected during the winter heating period in Northeast China; 35 from a lightly polluted region (group A), 40 from a moderately polluted region (group B) and 39 from a heavily polluted region (group C). Microbial genome DNA was extracted from throat swab samples to study the oral flora composition of the volunteers by amplifying and sequencing the V3 regions of prokaryotic 16S rRNA. Lung function tests were also performed.

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Recent Advances in Protein Kinase Activity Analysis Based on Nanomaterials.

Int J Mol Sci

March 2019

Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Key Lab of Bioorganic Phosphorus Chemistry and Chemical Biology of Ministry of Education, Tsinghua University, Beijing 100084, China.

Protein phosphorylation regulated by protein kinases, as well as their dephosphorylation, is one of the most common post-translational modifications, and plays important roles in physiological activities, such as intracellular signal communications, gene transcription, cell proliferation and apoptosis. Over-expression of protein kinases is closely associated with various diseases. Consequently, accurate detection of protein kinases activities and their relevant inhibitors screening is critically important, not only to the biochemical research, but also to the clinical diagnosis and therapy.

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Mechanical characterization of functionally graded soft materials with ultrasound elastography.

Philos Trans A Math Phys Eng Sci

May 2019

1 AML, Department of Engineering Mechanics, Institute of Biomechanics and Medical Engineering, Tsinghua University, Beijing 100084 , People's Republic of China.

Functionally graded soft materials (FGSMs) with microstructures and mechanical properties exhibiting gradients across a spatial volume to satisfy specific functions have received interests in recent years. How to characterize the mechanical properties of these FGSMs in vivo/in situ and/or in a non-destructive manner is a great challenge. This paper investigates the use of ultrasound elastography in the mechanical characterization of FGSMs.

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Purification, characterization and tyrosinase inhibition activity of polysaccharides from chestnut (Castanea mollissima Bl.) kernel.

Int J Biol Macromol

June 2019

Department of Food Science and Engineering, College of Biological Sciences and Technology, Beijing Key Laboratory of Forest Food Process and Safety, Beijing Forestry University, Beijing 100083, China. Electronic address:

The present paper aimed to obtain the polysaccharides with potent tyrosinase inhibitory activity from chestnut kernel. The ultrasound extracted polysaccharide fractions 1-1 (UEP1-1) and UEP2-1 were obtained by successive ultrasound-assisted-extraction, DEAE-52 and Sephadex G-100 chromatography. The Fourier transform infrared spectrum revealed that both UEP1-1 and UEP2-1 had the characteristic absorption peaks of polysaccharides.

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Apatinib exerts anti-tumour effects on ovarian cancer cells.

Gynecol Oncol

April 2019

Department of Gynecology, Harbin Medical University Cancer Hospital, No. 150 Haping Road, Nangang District, Harbin 150040, Heilongjiang Province, China. Electronic address:

Objective: Apatinib, a small molecule inhibitor of VEGFR-2 tyrosine kinase, shows strong anti-tumour activity against various tumours. The function of apatinib in ovarian cancer, however, remains unclear. This study was conducted to investigate the effects and potential mechanisms by which apatinib modulates the biological function of ovarian cancer cells in vitro and in vivo.

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The effects of five types of tea solutions on epiboly process, neural and cardiovascular development, and locomotor capacity of zebrafish.

Cell Biol Toxicol

June 2019

Tianjin Key Laboratory of Tumor Microenvironment and Neurovascular Regulation, Department of Histology and Embryology, School of Medicine, Nankai University, Tianjin, 300071, China.

The effects of teas on embryonic development are still known little. The objective of this study was to compare and analyze developmental effects of green tea, delicate flavor oolong tea, strong flavor oolong tea, black tea, and pu'er tea using zebrafish embryos. Embryos were exposed in tea solutions from one-cell stage; the morphology, locomotor capacity, and gene expression of embryos or larvae were analyzed.

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A method for the determination of cholesterol and its six metabolism markers (desmosterol, lathosterol, campesterol, stigmasterol, -sitosterol, squalene) in serum by high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry (HPLC-Q/Orbitrap HRMS) was developed. The sample was ultrasonically extracted with acetonitrile. The separation was performed by using 95%(v/v) methanol-acetonitrile (2:8, v/v)-5%(v/v) water as the mobile phase.

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The construction of defects on TiO surface has attracted great interest due to their prominent effect on photocatalytic activity. However, most synthesis methods often lead to unstable oxygen vacancies which limits their effect for improvement of visible light photoactivity. In this work, stable oxygen vacancies were successfully introduced in commercial TiO (P25) one-step molten salt (MS) method.

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Massively parallel sequencing of microRNA in bloodstains and evaluation of environmental influences on miRNA candidates using realtime polymerase chain reaction.

Forensic Sci Int Genet

January 2019

CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100010, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; School of Forensic Medicine, Shanxi Medical University, Taiyuan 030001, PR China. Electronic address:

MicroRNAs (miRNA) are small (22-24 nucleotides) non-coding RNAs with potential application in forensic science because of their anti-degradation property and tissue specificity. Recent studies on the use of miRNA in forensic applications have mainly focused on body fluid identification using realtime polymerase chain reaction or microarray analysis. However, the exploration of miRNA in bloodstains, which are the most valuable source of biological evidence during case investigations, is currently lacking, particularly for aged and environmentally compromised forensic samples.

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MicroRNA profile analysis for discrimination of monozygotic twins using massively parallel sequencing and real-time PCR.

Forensic Sci Int Genet

January 2019

CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100010, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; School of Forensic Medicine, Shanxi Medical University, Taiyuan 030001, PR China. Electronic address:

In general, it is extremely problematic to discriminate between monozygotic twins (MZTs), who share the same genomic DNA sequence, using traditional DNA-based identification methods such as short tandem repeat profiling. MicroRNAs (miRNAs) have shown potential in forensic applications owing to their low molecular weight, abundant and tissue-specific expression. In this study, we utilized massively parallel sequencing technology to perform genome-wide profiling of miRNAs in the blood from four pairs of healthy MZTs.

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An atmospheric pressure laserspray ionization mass spectrometry (AP-LSI mini MS) has been developed and employed in the fast analysis of bacteria. Without using surfactants or any extracting methods, 21 foodborne bacteria from 12 genera were directly analyzed. Typical fingerprints of small molecules and lipids were detected and recognized in the mass spectra with high reproducibility.

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Fischer-Tropsch (FT) wax is an important material produced from FT synthesis reactions. In this study, an improved separation and identification method for FT wax by high temperature gas chromatography (HTGC) coupled with cold-on-column (without pretreatment) was developed. In our improved separation procedure, the carrier gas was changed to helium and a long chromatographic column was adapted for use at high temperature.

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Insights into the crystallinity and in vitro digestibility of chestnut starch during thermal processing.

Food Chem

December 2018

Department of Food Science and Engineering, College of Biological Sciences and Technology, Beijing Key Laboratory of Forest Food Process and Safety, Beijing Forestry University, Beijing 100083, China. Electronic address:

The crystallinity is of importance for in vitro digestibility of starch. Six chestnut cultivars were selected to study the relationship between the crystallinity and in vitro digestibility of chestnut starch during thermal processing. After heat treatment, the total starch and amylose content remained unchanged or decreased, but the amount of damaged starch increased significantly (P < 0.

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