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Determination of resveratrol in red wine by solid phase extraction-flow injection chemiluminescence method

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Chinese Chemical letters 2007年第8期18卷 985-988页

作者： juan juan Ren Hai Yan liu Yu Hong Hao Pin Gang He Yu Zhi Fang Department of Chemistry East China Normal University Shanghai 200062 China School of Chemistry and Molecular Engineering East China University of Science and Technology Shanghai 200237 China

A sensitive flow injection chemiluminescence method has been developed for the detection of resveratrol in red wine based on the fact that resveratrol can greatly enhance chemiluminescence reaction between KMnO4 and HCHO in sulfuric acid medium. Analytes were pre-concentrated on solid sorbents （C18 solid-phase extraction cartridges）. Under the optimum conditions, the proposed method allows the measurement of resveratrol over the range of 1.32 × 10^-8 to 1.32 × 10^-5 mol/l with a detection limit of 3.30 ×10^-9 mol/l, and the relative standard deviation for 1.32 ×10^-5 mol/l resveratrol （n = 11） is 3.8%. This method has been successfully applied for the determination of the resveratrol in red wine. Furthermore, the possible reaction mechanism was also discussed.

关键词： Resveratrol Solid phase extraction How-injection chemiluminescence Potassium permanganate Formaldehyde

Estimating distribution of water uptake with depth of winter wheat by hydrogen and oxygen stable isotopes under different irrigation depths

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Journal of Integrative Agriculture 2016年第4期15卷 891-906页

作者： GUO Fei MA juan-juan ZHENG li-jian SUN Xi-huan GUO Xiang-hong ZHANG Xue-lan College of Water Resource Science and Engineering Taiyuan University of TechnologyTaiyuan 030024P.R.China Shanxi Conservancy Technical College Yuncheng 044004P.R.China

Crop root system plays an important role in the water cycle of the soil-plant-atmosphere continuum. In this study, com- bined isotope techniques, root length density and root cell activity analysis were used to investigate the root water uptake mechanisms of winter wheat （Triticum aesfivum l.） under different irrigation depths in the North China Plain. Both direct inference approach and multisource linear mixing model were applied to estimate the distribution of water uptake with depth in six growing stages. Results showed that winter wheat under land surface irrigation treatment （Ts） mainly absorbed water from 10-20 cm soil layers in the wintering and green stages （66.9 and 72.0%, respectively）; 0-20 cm （57.0%） in the jointing stage; 0-40 （15.3%） and 80-180 cm （58.1%） in the heading stage; 60-80 （13.2%） and 180-220 cm （35.5%） in the filling stage; and 0-40 （46.8%） and 80-100 cm （31.0%） in the ripening stage. Winter wheat under whole soil layers irrigation treatment （Tw） absorbed more water from deep soil layer than Ts in heading, filling and ripening stages. Moreover, root cell activity and root length density of winter wheat under TW were significantly greater than that of Ts in the three stages. We concluded that distribution of water uptake with depth was affected by the availability of water sources, the root length density and root cell activity. Implementation of the whole soil layers irrigation method can affect root system distribution and thereby increase water use from deeper soil and enhance water use efficiency.

关键词： hydrogen and oxygen stable isotopes multisource linear mixing model winter wheat distribution of wateruptake with depth

The global climate monitor system:from climate data-handling to knowledge dissemination

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International Journal of Digital Earth 2019年第4期12卷 394-414页

作者： juan Mariano Camarillo-Naranjo José Ignacio Álvarez-Francoso Natalia limones-Rodríguez María Fernanda Pita-lópez Mónica Aguilar-Alba Department of Physical Geography and Regional Analysis University of SevilleSevilleSpain Department of Human Geography University of SevilleSevilleSpain

This paper summarizes our work on building a data model and a geovisualization tool that provides access to global climate data:the Global Climate Monitor Web *** to this viewer,a complete set of climate-environmental indicators capable of displaying climate patterns on a global scale that is accessible to any potential user(scientists and laypeople)will be built and published using the same online *** data currently available correspond to the CRU TS3.21 version of the Climate Research Unit(University of East Anglia)database–a product that provides data at a spatial resolution of half of a degree in latitude and longitude,spanning January 1901 to December 2012,on a monthly *** January 2013,the datasets feeding the system have been the GHCN-CAMS temperature dataset and the Global Precipitation Climatology Centre(GPCC)First Guess precipitation ***,hydrologists,planners and non-experts users such as media workers,policymakers,non-profit organizations,teachers or students,can access useful climatological information through the Global Climate Monitor system.

关键词： Geovisualization climate indicators global climate databases open-source software

Plasma-induced, nitrogen-doped graphene-based aerogels for high-performance supercapacitors

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light(Science & Applications) 2016年第1期5卷 583-589页

作者： Xue-Yu Zhang Shi-Han Sun Xiao-juan Sun Yan-Rong Zhao li Chen Yue Yang Wei lü Da-Bing li Key laboratory of Advanced Structural Materials Ministry of Education&Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China State Key laboratory of luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Basic Sciences&Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China

Commonly used energy storage devices include stacked layers of active materials on two-dimensional sheets,and the limited specific surface area restricts the further development of energy ***-dimensional(3D)structures with high specific surface areas would improve device ***,we present a novel procedure to fabricate macroscopic,high-quality,nitrogen-doped,3D graphene/nanoparticle *** procedure includes vacuum filtration,freeze-drying,and plasma treatment,which can be further expanded for large-scale production of nitrogen-doped,graphene-based *** behavior of the supercapacitor is investigated using a typical nitrogen-doped graphene/Fe_(3)O_(4) nanoparticle 3D structure(NG/Fe_(3)O_(4)).Compared with 3D graphene/Fe_(3)O_(4) structures prepared by the traditional hydrothermal method,the NG/Fe_(3)O_(4) supercapacitor prepared by the present method has a 153%improvement in specific capacitance,and there is no obvious decrease in specific capacitance after 1000 *** present work provides a new and facile method to produce large-scale,3D,graphene-based materials with high specific capacitance for energy storage.

关键词： energy storage N-doping plasma three-dimension

Nonlocal and strain gradient effects on nonlinear forced vibration of axially moving nanobeams under internal resonance conditions

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Applied Mathematics and Mechanics(English Edition) 2020年第2期41卷 261-278页

作者： Jing WANG Yilin ZHU Bo ZHANG Huoming SHEN juan lIU School of Mechanical and Electrical Engineering Southwest Petroleum UniversityChengdu 610500China School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500China School of Mechanics and Engineering Southwest Jiaotong UniversityChengdu 611756China Applied Mechanics and Structure Safety Key laboratory of Sichuan Province Chengdu 611756China

Based on the nonlocal strain gradient theory(NSGT), a model is proposed for an axially moving nanobeam with two kinds of scale effects. The internal resonanceaccompanied fundamental harmonic response of the external excitation frequency in the vicinities of the first and second natural frequencies is studied by adopting the multivariate lindstedt-Poincaré(l-P) method. Based on the root discriminant of the frequencyamplitude equation under internal resonance conditions, theoretical analyses are performed to investigate the scale effects of the resonance region and the critical external excitation amplitude. Numerical results show that the region of internal resonance is related to the amplitude of the external excitation. Particularly, the internal resonance disappears after a certain critical value of the external excitation amplitude is *** is also shown that the scale parameters, i.e., the nonlocal parameters and the material characteristic length parameters, respectively, reduce and increase the critical amplitude,leading to a promotion or suppression of the occurrence of internal resonance. In addition,the scale parameters affect the size of the enclosed loop of the bifurcated solution curves as well by changing their intersection, divergence, or tangency.

关键词： scale effect axially moving nanobeam internal resonance critical amplitude

Microstructure, tensile properties and mechanical anisotropy of selective laser melted 304l stainless steel

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Journal of Materials Science & Technology 2020年第13期47卷 63-71页

作者： juan Hou Wei Chen Zhuoer Chen Kai Zhang Aijun Huang School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Monash Center for Additive Manufacturing(MCAM) Monash UniversityNotting HillVIC 3168Australia

The microstructure and mechanical properties of 304 l stainless steel fabricated by selective laser melting are investigated in this *** the optimized laser processing parameters,a relative density of 99.9%is achieved with fine austenite grains and nanoscale cellular subgrains in size of approximately 0.5μ*** presence ofδ-ferrite andσphase precipitates is identified by the x-ray diffraction and transmission electron ***,the microstructure is identified as an austenite matrix with about 4%δ-ferrite and a trace amount ofσphase by using electron backscattered diffraction *** smallσphase particles are mainly distributed along austenite grain ***,the presence of nanoscale cellular subgrains contributes to the good tensile strength and ductility of the selective laser melted 304 l,along with precipitate strengthening and strain *** property anisotropy is also identified in this 304 l,which is attributed to the microstructure difference on vertical and horizontal planes.

关键词： Selective laser melting Microstructure Tensile property anisotropy 304l stainless steel

Chemical composition and larvicidal effects of essential oil of Blumea martiniana against Anopheles anthropophagus

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 371-374页

作者： liang Zhu Ying-juan Tian College of Food and Bioengineering South China University of TechnologyGuangzhouGuangdong ProvinceChina

Objective:To determine chemical composition of the hydrodistilled essential oil of Blumea martiniana,and to evaluate its larvicidal activity against Anopheles anthropophagus,the natural vector of ***:Chemical composition of essential oils extracted by steam distillation was investigated by gas chromatography and mass spectroscopy（GC-MS）.larvicidal activity of essential oil and its four main compounds was carried out by WHO *** larvae of early fourth-instar stage were used in the larvicidal assay and five replicates were maintained for each *** 24 h lC50 and lC90 values were determined following probit ***:Totally 68 compounds corresponding to 98.55%of the total oil were identified and the major constituents of essential oil were:linalool（10.36%）,germacrene D（9.09%）, borneol（6.24%）,γ-terpinene（5.38%）.The oil and linalool,germacrene D,bomeol,γ-terpinene exerted significant larvicidal activity with lC50 values of 46.86,35.87,44.61,35.89,and 29.21 mg/l, *** also showed a dose dependent effect on ***:The essential oil of Blumea martiniana and its four major compounds may have potential for use in control of Anopheles anthropophagus larvae and could be useful in search of newer,safer and more effective natural compounds as larvicides.

关键词： Blumea martiniana Essential oil Composition larvicidal Anopheles anthropophagus

Molecular Characterization and Functional Analysis of OsPHY1,a Purple Acid Phosphatase (PAP)-Type Phytase Gene in Rice (Oryza sativa l.)

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Journal of Integrative Agriculture 2012年第8期11卷 1217-1226页

作者： lI Rui-juan lU Wen-jing GUO Cheng-jin lI Xiao-juan GU Jtm-tao XIAO Kai College of life Sciences Agricultural University ofHebei Baoding 071001 P.R. China College of Agronomy Agricultural University of Hebei Baoding 071001 P.R. China

As a specific type of acid phosphatses, phytases play diverse roles in plants by catalazing the degradation of phytic acid and its derivatives. In this study, a rice phytase gene referred to OsPHY1 has been functionally characterized. OsPHY1 contains a 1 620 bp of open reading frame, encoding a 539-aa polypeptide. A conserve domain metallophosphatase （MPP）（MPP_PAPs）, generally harbored in phytase and purple acid phosphatases （PAP）, was identified in OsPHY1 （residue 194-398）. Phylogenetic analysis revealed that OsPHY1 shares high similarities with phytase genes and PAP-type genes that derived from diverse plant species. The OsPHY1 transcripts were detected to be abundant in germinating seeds, suggesting that this gene plays potential roles on degradation of seed phytic acid and its derivatives during the germination process. Biochemical analysis confirmed that OsPHY1 possesses strong catalytic activities on phytic acid-Na2, with optimal temperature of 57°C and suitable pH of 3.5. Based on transgene analysis, the putative role of OsPHY1 in plants on utilization of phytate was assessed. Under the condition that phytic acid-Na2 was used as sole P source, the OsPHY1-overexpressing tobacco plants behaved higher phytase activities, higher concentrations of Pi, more accumulative amount of total phosphorus, and much more improved growth traits than those of the control plants. Therefore, OsPHY1 is acted as an important component on degradation of the phytins during the seed germination process in rice. Also, OsPHY1 has a potential use on generation of elite crop germplasms with improved use efficiencies on phytate and its derivatives.

关键词： rice (Oryza sitava l.) phytase expression transgenic tobacco phosphorus utilization efficiency

Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex

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Asian Journal of Andrology 2016年第6期18卷 858-862页

作者： Pilar Santolaria Alfredo Pauciullo Miguel A Silvestre Sandra Vicente-Fiel leyre Villanova Alain Pinton juan Viruel Ester Sales Jesus l Yaniz TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Animal Production and Food Sciences Higher Polytechnic School University of Zaragoza Ctra. Cuarte SIN 22071 Huesca Spain Department of Agriculture Forest and Food Sciences University of Torino Largo Paolo Braccini 2 10095 Grugliasco TO Italy Department of Functional Biology and Physical Anthropology University of Valencia 469100 Burjassot Valencia Spain UMR 1388 INRA-ENVT INPT Animal Cytogenetis GenPhySE National veterinary school of Toulouse 23 Chemin des Capelles 31076 Toulouse Cedex 3 France Mediterranean Institute of marine and terrestrial Biodiversity and Ecology (IMBE) University of Aix Marseille Chemin de la Batterie des Lions 13007 Marseille France TECNOGAM research group Environmental Sciences Institute (IUCA) Department of Agricultural and Environmental Sciences Higher Polytechnic School University of Zaragoza Ctra. Cuarte S/N 22071 Huesca Spain

This study was designed to determine the ability of computer-assisted sperm morphometry analysis （CASA-Morph） with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa （SX and SY, respectively）. Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average （P 〈 0.001） although with important differences between bulls. A simultaneous evaluation of all the measured features by discriminant analysis revealed that nuclear area and average fluorescence intensity were the variables selected by stepwise discriminant function analysis as the best discriminators between SX and SY. In the second experiment, the sperm nuclear morphometric results from CASA-Morph in nonsexed （mixed SX and SY） and sexed （SX） semen samples from four bulls were compared. FISH allowed a successful classification of spermatozoa according to their sex chromosome content. X-sexed spermatozoa displayed a larger size and fluorescence intensity than nonsexed spermatozoa （P 〈 0.05）. We conclude that the CASA-Morph fluorescence-based method has the potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

关键词： bull computer-assisted sperm morphometry analysis sexing sperm morphometry