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1.
This work reports the photoluminescence properties of Ca3Mg3(PO4)4:Sm3+ phosphors that were synthesized by the combustion method. The phase formation and morphology of the prepared phosphors were analysed by X‐ray diffraction studies and scanning electron microscopy. Ca3Mg3(PO4)4:Sm3+ phosphors give orange light emission when excited by near‐ultraviolet (NUV) and blue light. The photoluminescence characteristics of the as‐prepared phosphors were investigated and their emission spectra showed three peaks due to 4G5/2 → 6H5/2, 4G5/2 → 6H7/2 and 4G5/2 → 6H9/2 transitions. The mechanism responsible for the concentration quenching of luminescence was found to be an electric dipole–dipole interaction. The CIE chromaticity coordinates suggested that the prepared phosphors are potential candidates for orange light‐emitting diodes (LEDs). 相似文献
2.
Molecular mechanism of feedback regulation of 17β‐estradiol on two kiss genes in the protogynous orange‐spotted grouper (Epinephelus coioides) 下载免费PDF全文
3.
以生长一致的红肉脐橙成年植株为试材,研究了果实转色前外源GA3 和ABA 处理对果实品质的影响。结果表明,外源GA3处理提高了果皮亮度,但降低了果皮红色度、黄色度和单果重;ABA 处理提高了果皮红色度,但降低了果皮亮度;GA3 100mg/L 处理虽然极显著降低了果皮厚度, 极显著提高了果皮亮度、可溶性固形物和VitC 含量, 但同时极显著降低了果皮红色度、糖酸比,并极显著提高了果实含酸量; 外源ABA处理还极显著降低了果实可食率、出汁率和VitC 含量。因此,在果实转色前用外源GA3和ABA 处理红肉脐橙果实均不利于其综合品质的提高。 相似文献
4.
W. A. B. de Almeida F. de A. A. Mourao Filho B. M. J. Mendes A. P. M. Rodriguez 《Biologia Plantarum》2006,50(3):321-325
The adventitious bud development was induced in epicotyl segments of Valencia sweet orange (Citrus sinensis L. Osbeck). Seeds were cultured in vitro for three weeks in the dark, followed by one week at a 16-h photoperiod. Epicotyl segments were cultured horizontally for
the induction of organogenesis in Murashige and Tucker (1969, MT) culture medium supplemented with 1.0 mg dm−3 benzylaminopurine. Samples were observed by light and scanning electron microscopy from day zero to day 25, when buds were
well grown. It was shown that the adventitious buds originated directly from the cambial region on the cut ends of the explants. 相似文献
5.
Ana Lúcia Biggi de Souza Cléa dos Santos Ferreira Mariano Sílvia das Graças Pompolo José Eduardo Serrão 《法国昆虫学会纪事》2013,49(3-4):510-513
Wasmannia auropunctata is known as one of the worst invasive ants in the World. A cytogenetic study was conducted on two native populations from southeastern Bahia, Brazil. The analysis of the chromosomes observed in mitotic metaphases was made by a combination of methods: Giemsa conventional staining, chromomycin A3 (CMA3) and 4-6-diamidino-2-phenylindole (DAPI) fluorochrome staining, and acridine orange banding. The workers have all the karyotype 2n=32, with ten pairs of metacentric and six pairs of acrocentric chromosomes. One chromosome arm of the pair ten was positive for CMA3 and acridine orange, suggesting the occurrence of a nucleolar organizing region. This region is an interesting marker because is very conservative and seems to constitute an interesting specific taxonomic character. The pericentromeric region of many chromosomes was stained with DAPI, evidencing the occurrence of AT bases rich heterochromatin. 相似文献
6.
7.
C. J. Cooksey 《Biotechnic & histochemistry》2013,88(7):527-532
ABSTRACTThe identities of 18 dyes whose names begin with “Victoria” are described using their chemical structures, names and numerical identifiers. All are synthetic dyes originally synthesized in Germany during the late 19th century as colorants for textiles. Brief manufacturing details are included. All the colors of the rainbow are represented except indigo. Unusual properties including explosive tendency or toxicity are noted. Some of the applications as stains and for food coloring, anti-obesity medication and pigments for ball pen inks also are discussed 相似文献
8.
Neng-Guo Tao Juan Xu Yun-Jiang Cheng Xiu-Xin Deng 《植物学报(英文版)》2006,48(3):315-319
A cDNA library was constructed end characterized from the pulp of Cera Care navel orange (Citrus sinensis Osbeck) at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke (MT) gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng. 相似文献
9.
Ilona Fitos Júlia VisyFerenc Zsila György MádyMiklós Simonyi 《Biochimica et Biophysica Acta (BBA)/General Subjects》2006
Imatinib is a selective tyrosine kinase inhibitor, successfully used for the treatment of chronic myelogenous leukaemia. Its strong plasma protein binding referred to α1-acid glycoprotein (AGP) component was found to inhibit the pharmacological activity. AGP shows genetic polymorphism and the two main genetic variants have different drug binding properties. The binding characteristics of imatinib to AGP genetic variants and the possibility of its binding interactions were investigated by various methods. The results proved that binding of imatinib to the two main genetic variants is very different, the high affinity binding belongs dominantly to the F1-S variant. This interaction is accompanied with specific spectral changes (induced circular dichroism, UV change, intrinsic fluorescence quenching), suggesting that the bound ligand has chiral conformation that would largely overlap with other ligands inside the protein cavity. Binding parameters of Ka = 1.7(± 0.2) × 106 M− 1 and n = 0.94 could be determined for the binding on the F1-S variant at 37°. Imatinib binding on the A variant is weaker and less specific. The binding affinity of imatinib to human serum albumin (nKa ≈ 3 × 104 M− 1) is low. Pharmacologically relevant binding interactions with other drugs can be expected on the F1-S variant of AGP. 相似文献
10.
Nikos T. Papadopoulos Todd E. Shelly Nuri Niyazi Eric Jang 《Journal of Insect Behavior》2006,19(3):403-418
Males of the Mediterranean fruit fly, Ceratitis capitata, are strongly attracted to various plant odors, and previous work has demonstrated that male exposure to certain odors, including the scent of orange oil (OO) and ginger root oil (GRO), increases their mating success relative to non-exposed males. However, the mechanism(s) underlying this mating increase is not known. Here, we describe several experiments that further investigate the association between GRO- and OO-exposure and male signaling activity, pheromone attractiveness, and mating success in male medflies. Exposure to GRO or OO increased time spent pheromone calling but did not accelerate the rate of male sexual maturation. Using a wind tunnel, we compared female attraction to the pheromone of control, non-exposed males versus males previously exposed to OO or GRO. There was no evidence that GRO exposure enhanced the attractiveness of the male pheromone. The data for OO were inconclusive: females tended to spend more time on spheres emanating pheromone from OO-exposed males than on spheres emanating pheromone from non-exposed males, but the number of female landings did not differ between the two types of pheromone sources. Female choice tests confirmed that GRO- and OO-exposure boost male mating success relative to non-exposed males. Application of GRO directly to the abdomen reduced male mating success, whereas similar application of OO boosted male mating success. The potential role and mode of action of plant chemicals in the mating behavior of male medflies are evaluated in light of these findings. 相似文献