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Olive oil history,production and by-product management 总被引:1,自引:0,他引:1
Iosif Emmanouil Kapellakis Konstantinos P. Tsagarakis John C. Crowther 《Reviews in Environmental Science and Biotechnology》2008,7(1):1-26
In this review paper, the history of the olive tree and the development of the main olive oil extraction systems employed
in the past are presented. Furthermore, the management techniques employed from antiquity until today for the treatment of
olive mill wastewater (OMW), which constitutes the most important by-product of olive oil production, are addressed and compared.
Reference is also made to global olive oil production, the environmental impacts of the uncontrolled disposal of OMW, and
to the legal framework concerning its management in the main olive oil producing countries. Other by-products of olive processing
are also discussed. 相似文献
3.
Synthesis and luminescence characterization of Y2BaZnO5:RE (RE = Eu3+, Tb3+, Pr3+ and Sm3+) phosphors 下载免费PDF全文
Modified synthesis and luminescence of Y2BaZnO5 phosphors activated with the rare earths (RE) Eu3+, Tb3+, Pr3+ and Sm3+ are reported. RE2BaZnO5 phosphors have attracted attention because of their interesting magnetic and optical properties; and are usually prepared using a two‐step solid‐state reaction. In the first step, carbonates or similar precursors are thoroughly mixed and heated at 900°C to decompose them to oxides. To eliminate the unwanted phases like BaRE2O4, the resulting powders are reheated at 1100°C for a long time. We prepared Y2BaZnO5 phosphors activated with various activators by replacing the first step with combustion synthesis. The photoluminescence results are presented. The photoluminescence results for Eu3+, Tb3+ and Pr3+ are in good agreement with the literature. However, photoluminescence emission from Sm3+ has not been documented previously. The excitation spectrum of Eu3+ is dominated by a charge transfer band around 261 nm, and an additional band around 238 nm is always present, irrespective of the type of activator. The presence of this band for all these different types of activators was interpreted as host absorption. 相似文献
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COI序列:影响动物分类学与生态学的DNA barcode 总被引:3,自引:0,他引:3
DNA barcode是一段特殊的、可用于物种鉴定的DNA序列.目前在动物中最常用的DNA barcode是细胞色素C氧化酶1号基因(COI)的部分序列.随着标准数据库的建立,基于COI基因的DNA barcode在动物分类学和生态学中得到了广泛应用.但是,采用COI基因作为DNA barcode所隐含的涉及线粒体的进化历史、遗传特性和物种成种时间的默认前提,并非完全成立,由此引发了许多问题.本文阐述了基于COI基因的DNA barcode对分类学和生态学的影响,目前存在的问题,以及可能的研究方向. 相似文献
5.
Promotion of indole alkaloid production in Catharanthus roseus cell cultures by rare earth elements 总被引:3,自引:0,他引:3
Production of the indole alkaloids, ajmalicine or catharanthine, in cell suspension cultures of Catharanthus roseus was enhanced by cerium (CeO2 and CeCl3), yttrium (Y2O3) and neodymium (NdCl3). The yield of ajmalicine in these treated-cultures reached 51 mg l–1 (CeO2), 40 mg l–1 (CeCl3), 41 mg l–1 (Y2O3) and 49 mg l–1 (NdCl3) while catharanthine production reached to 36 mg l–1 (CeO2) and 31 mg l–1 (CeCl3). A major portion of increased alkaloids was released into medium in these treatments. But Sm2O3, SmCl3, La2O3, LaCl3, complex of chromium (III)-titanium (IV) and NaSeO4 treatments had little effect on alkaloid production of C. roseus cell cultures. 相似文献
6.
Cheng Qi Ao 《Journal of Plant Biology》2008,51(2):116-121
Platycrater arguta Sieb. et Zucc. is a rare and endangered species endemic to East Asia. It produces two floral morphs viz. bisexual and male
flowers. For bisexual flowers, simultaneous cytokinesis in the microsporocyte meiosis leads to a tetrahedral tetrad. The mature
pollen grain is shed at 2-cell stage. The young anther wall is composed of epidermis, endothecium that develops fibrous thickenings
at maturity, 1–2 middle layers and tapetum. The tapetum with uninucleate to binucleate cells, disintegrates in situ (glandular
tapetum), yet in a small percentage of the anthers (about 37.6%), the tapetum does not disintegrate, causing complete male
sterility. The ovules are anatropous, unitegmic, tenuinucellar and the formation of the embryo sac follows the monosporic,
Polygonum type. Antipodal cells are lacking in the mature embryo sacs. Before fertilization, two polar nuclei fuse into a
secondary nucleus. The formation of microsporangial wall, microsporogenesis and male gametogenesis in male flowers are analogous
to those in the bisexual. Prezygotic embryological characters ofP. arguta were reported for the first time, revealing that its endangerment is correlated with the abortion of pollen of a part but
not to the female development that is normal. 相似文献
7.
The synthesis and characterization of rare-earth (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y) thiocyanate adducts with tripiperidinophosphine oxide (tpppO) with general formula (RE)(SCN)3(tpppO)3 are reported. Conductance measurements in acetonitrile indicate the non-electrolytic nature of the complexes. Infrared absorption spectra evidence that the SCN− ion coordinates through the nitrogen atom (isothiocyanate form) and that tpppO coordinates through the phosphoryl oxygen. X-ray powder patterns suggest the existence of three different crystal forms: (1) La; (2) an isomorphous series including Ce, Nd and Pr; and (3) another isomorphous series, including Sm, Gd, Eu, Ho, Er, Tb, Lu and Y. The visible spectra of the Nd adduct and the calculated parameters β = 0.98, b1/2 = 0.072 and δ = 1.06 indicate that the metal-ligand bonds are essentially electrostactic. The emission spectra of the Eu compound showed 5D0 → 7FJ bands (J = 0, 1, 2), suggesting a C3v symmetry for the coordination polyhedron. The lifetime of the 5D0 state is 1.28 ms. The emission spectra of the Tb complex presented 5D4 → 7FJ bands (J = 4, 5, 6) and the Dy complex showed the 4F9/2 → 6H13/2 band. The structure of the Pr complex showed that the coordination polyhedron is a trigonal antiprism, with the isothiocyanate anions in one base and three tpppO ligands in the other. Thermal analyses (TG-DTG) were carried out for the Ce, Nd and Gd adducts. Mass losses start between 250 and 334 °C. The final residues at 1300 °C are the corresponding phosphates. 相似文献
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