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1.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

2.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

3.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

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This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.  相似文献   

7.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the  相似文献   

8.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

9.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

10.
《印刷工业》2014,(12):102-103
Sponsored by Printing and Printing Equipment Industries Association of China (PEIAC) and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference (INFOPRINT 2014) was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.  相似文献   

11.
正In September 2013,OJI(Qingdao)Bag Manufacture Co.Ltd.and Wuhan South OJI Packing Co.Ltd.invested by OJI Group in China have put into operation in succession,and the opening ceremony was held on September 4th and 5th respectively.  相似文献   

12.
《造纸信息》2014,(8):106-106
On April 25th, 2014, Guangdong Guanhao High -Tech Co., Ltd. held the trial production ceremony of the specialty paper and coated paper industry base project (first phase) at the base paper production plant of Donghai Island m  相似文献   

13.
《造纸信息》2014,(8):76-77
On December 25th, 2013, the Ministry of Industry and Information Technology published "Directory of Process Technology and Equipment for Industrial Water Saving Encouraged by the State (First Edition)" (Draft) on its website.  相似文献   

14.
Zusammenfassung Der Wanderfalke war als Baumbrüter mit über 1000 Brutpaaren über das europäische Tiefland von Deutschland bis Russland verbreitet. In Nord - und Ostdeutschland existierte eine ca. 500 Brutpaare starke reine Baumbrüterpopulation, in der nur ganz wenige Fels- und Gebäudebruten vorkamen und die an den Folgen chemischer Schädlingsbekämpfungsmittel in der Nahrungskette nach 1972 vollständig ausstarb wie im gesamten Baumbrütergebiet. Die Gewohnheit auf Bäumen zu nisten beruht beim Wanderfalken offensichtlich auf Prägung und Traditionsbildung. Unter dieser Voraussetzung wurde 1990 ein Wiederansiedlungsprogramm mit Prägung gezüchteter Jungvögel auf Baumbruthabitat während ihrer Auswilderung begonnen, und es wird bis zum Erreichen von 20 Baumbrutansiedlungen im deutschen Baumbrüterareal forgesetzt. Bisher wurden 201 Falken erfolgreich ausgewildert; zusätzliche 29 flogen von 3 Wildparren aus, die seit 1996 in Kiefernalthölzern angesiedelt gefunden wurden. Alle Vögel der seit 1981 neu entstandenen ostdeutschen Wanderfalkenpopulation sind durch Ringkombinationen individuell gekennzeichnet nach ihrer Herkunft aus Baum-, Fels- oder Gebäudebruten sowie aus Auswilderungen oder Wildbruten. Auch Jahrgang und Herkunftsrevier lassen sich fernoptisch bei den angesiedelten Brutpaaren ablesen. Zur Erfolgskontrolle wurde eine Überlebenstafel berechnet (Tabelle), die für das Jahr 2000 insgesamt 22 brutreife Wanderfalken aus der Auswilderung und aus den Wildbruten zusammen erwarten ließ. 9 Falken an den drei bisher gefundenen Baumbrutansiedlungen stammen alle aus dem Projekt, womit die Wirksamkeit der Prägung erwiesen ist. Weitere 11 Individuen aus dem Projekt wurden als Partner von Gebäude-und Felsbruten gefunden. Das entspricht ca. 50 % Rückkehr zur angeborenen Nistweise, aber bisher gab es keinen einzigen Wechsel von Gebäude- oder Felsbrütern zur Baumbrut. Der Austausch zwischen den Bruttypen entspricht also einer Einbahnstraße mit Sperrrichtung zur Baumbrut. Nach diesem neuen Befund kann sich eine Baumbrüterpopulation nur dort entwickeln und behaupten, wo Nistmöglichkeiten an Felsen oder Gebäuden nicht oder sehr spärlich vorhanden sind. Deshalb keine Nisthilfen an Gebäuden im Baumbrüterareal anbringen! Der erreichte Anfangserfolg ist erst dann gesichert, wenn im Baumbrüterareal mehr auf Baumbrut geprägte Wanderfalken ausfliegen als aus Gebäudebruten. Rechtzeitiger Schutz vor Artenschwund sollte in jedem Fall Vorrang vor aufwendiger und nicht immer durchführbarer Wiedereinbürgerung haben.  相似文献   

15.
Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented.  相似文献   

16.
ABSTRACT

Honey samples from Switzerland were investigated with regard to their microplastic particle burden. Five representative honey samples of different origin were processed following a standardized protocol to separate plastic-based microparticles from particles of natural origin, such as pollen, propolis, wax, and bee-related debris. The procedure was optimized to minimize post-sampling microplastic cross-contamination in the laboratory. The isolated microplastic particles were characterized and grouped by means of light microscopy as well as chemically characterized by microscopically coupled Raman and Fourier transform infrared spectroscopy. Five particle classes with an abundance significantly above blank levels were identified: black particles (particle count between 1760/kg and 8680/kg), white transparent fibres (particle count between 132/kg and 728/kg), white transparent particles (particle count between 60/kg and 172/kg), coloured fibres (particle count between 32/kg and 108/kg), and coloured particles (particle count between 8/kg and 64/kg). The black particles, which represented the majority of particles, were identified as char or soot and most probably originated from the use of smokers, a widespread practice in beekeeping. The majority of fibres were identified as cellulose or polyethylene terephthalate and were most likely of textile origin. In addition to these particle and fibre groups lower numbers of fragments were detected that were related to glass, polysaccharides or chitin, and few bluish particles contained copper phthalocyanine pigment. We found no indications that the honey samples were significantly contaminated with microplastic particles.  相似文献   

17.
倪士敏 《纺织器材》2013,40(3):44-51
阐述棉纺牵伸胶辊、胶圈的应用技术和牵伸原理,重点探讨了胶辊、胶圈的牵伸工艺特性及其合理配置、胶辊制作、周期管理、质量管理、使用管理、产品缺陷与其机械波分析、纺纱环境和挡车工操作水平对纺纱性能的影响,提出胶辊、胶圈有关机件的质量要求等。  相似文献   

18.
The concept of toxic equivalency factors (TEFs) has been developed to facilitate risk assessment and regulatory control of exposure to complex PCDD, PCDF and PCB mixtures. Recently the European Centre for Environment and Health of the World Health Organization (WHO-ECEH) and the International Programme on Chemical Safety (IPCS) jointly reevaluated the TEFs of PCDDs, PCDFs and dioxin-like PCBs for mammals and derived consensus TEFs for birds and fish (Stockholm, 1997). From a mechanistic point of view it can be concluded that, although the quantitative response will vary depending on the congener involved, the occurrence of a common mechanism (binding to the Ah receptor) legitimates the use of the TEF concept across species. But there also is criticism regarding the TEF concept. Pharmacokinetic differences between species can significantly influence the TEF value, and uncertainties due to additive or nonadditive interactions, to differences in species responsiveness and to differences in the shape of the dose response curve might hamper the derivation of consensus TEF values. In this context it should be noted, however, that using TCDD alone, as the only measure of exposure to dioxin-like PCDDs, PCDFs and PCBs, would severely underestimate the risk from exposure to these compounds. Therefore, it can be concluded that, for pragmatic reasons, the TEF concept remains the most feasible approach for risk assessment purposes, in spite of the uncertainties associated with its use.  相似文献   

19.
This monograph traces the various means by which flax fibre is transformed into linen yarns and fabrics. The principal innovations and developments of the past fifty years are identified. An extensive range of relevant literature is reviewed. Details are given of how the fibre is extracted from the stem of the flax plant and of the stages of yarn and fabric production. An explanation is given of how yarns are produced from short fibres (known as tow) using carding, drafting and dry spinning, and from long fibres (known as line) using hackling, drafting, doubling, roving and wet spinning in warm water. Further areas covered include yarn winding, linen weaving, dyeing and finishing. New applications for flax fibre, beyond traditional uses in apparel or furnishing fabrics, are also identified.  相似文献   

20.
动态称量过程的计算机控制   总被引:3,自引:3,他引:0  
针对面粉等加工自动控制中存在的不足 ,设计了一套机电一体化的动态称量过程计算机控制系统 ,采用单片计算机配以测控接口和应用软件 ,实现对机械下料过程的动态检测和定量控制 ,解决了面粉加工等过程中动态称量过程计量精度与可靠性问题  相似文献   

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