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11.
Effendy Corrado Di Nicola Brian W. Skelton Allan H. White 《Inorganica chimica acta》2005,358(3):763-795
Single crystal X-ray structural characterizations are recorded for a wide range of adducts of the form MX:dppx (1:1)(n), M = silver(I) (predominantly), copper(I), X = simple (pseudo-) halide or oxy-anion (the latter spanning, where accessible, perchlorate, nitrate, carboxylate - a range of increasing basicity), dppx=bis(diphenylphosphino)alkane, Ph2P(CH2)xPPh2, x = 3-6. Adducts are defined of two binuclear forms: (i) [LM(μ-X)2L], with each ligand chelating a single metal atom, and (ii) [M(μ-X)2(μ-(P-L-P′))2M′] where both ligands L and halides bridge the two metal atoms; a few adducts are defined as polymers, the ligands connecting M(μ-X)2M′ kernels, this motif persisting in all forms. Synthetic procedures for all adducts have been reported. All compounds have been characterized both in solution (1H, 13C, 31P NMR, ESI MS) and in the solid state (IR). 相似文献
12.
Effendy Claudio Pettinari Massimo Ricciutelli Allan H. White 《Inorganica chimica acta》2005,358(13):4009-4018
1:2, 1:1, 3:2 and 6:2 AgX:L adducts (where L is a tridentate phosphine, in detail: 1,1,1-tris(diphenylphosphinomethyl)ethane (Me-triphos) and bis(2-diphenylphosphinoethyl)phenylphosphine (Ph-triphos), X = O3SCF3, O3SCH3, BF4 or O2CCF3) have been synthesized and characterized by IR, NMR (1H, 31P and 19F) and ESI MS spectroscopy. The stoichiometry of the complexes is strongly dependent on the ligand to metal ratio employed and also on the nature of the counterion. 31P NMR (solution) data also show the complexes existing in solution, in some cases, however, disproportionating to adducts of different nuclearity. Oligonuclear species have been detected through ESI MS spectroscopy that has been demonstrated as a powerful tool for the identification of the solution species. AgBF4:Me-triphos (1:2) has been structurally characterized as [Ag(P,P′-Me-triphos)2](BF4) · H2O · 7/2 MeOH, while Ag(O3SCF3): Ph-triphos: H2O (6:2:4) is a spectacular two-dimensional polymer. 相似文献
13.
通过采用银染法鉴别短串联重复序列聚合酶链式反应(STR)位点的PCR产物来鉴别人二倍体细胞MRC-5株主细胞库、工作细胞库及限制代细胞。运用PCR方法对细胞库的9个STR位点(CSF1PO、TPOX、TH01、F13A01、FESFPS、vWA、D16S539、D7S820、D13S317)和性别鉴别位点Am elogen in进行扩增,变性聚丙烯酰胺凝胶电泳分离,银染法显影技术,检测MRC-5主细胞库、工作细胞库及限制代细胞的遗传标记。与ATCC公布的MRC-5的荧光STR图谱的8个STR位点和Am elogen in位点相比,MRC-5主细胞库、工作细胞库、限制代细胞的银染STR图谱的9个STR位点和Am elogen in位点,荧光法和银染法重叠的8个位点(CSF1PO、TPOX、TH01、FESFPS、vWA、D16S539、D7S820、D13S317和Am elogen in)数据完全吻合,说明细胞鉴别试验成立。STR图谱作为细胞鉴别的方法简单、易行、准确。 相似文献
14.
Horst Kunkely 《Inorganica chimica acta》2006,359(1):388-390
The complexes AgI(tripod)X with tripod = 1,1,1-tris(diphenylphosphinomethyl)ethane and X− = Cl− and I− are luminescent in solution at r.t. It is suggested that the emission is a phosphorescence which originates from a tripod intraligand state for X = Cl (λmax = 464 nm) and a X− → tripod ligand-to-ligand charge transfer state for X = I (λmax = 482 nm). 相似文献
15.
M. L. Merroun N. Ben Omar E. Alonso J. M. Arias M. T. GonzÁlez-MuÑoz 《Geomicrobiology journal》2013,30(2):183-192
This paper deals with silver sorption to Myxococcus xanthus biomass. The dry biomass of this microorganism is shown to be a good sorbent for the recovery of silver present at low solution concentrations. Between initial silver concentrations of 2 and 0.05 mM, the percentage of accumulation ranges from 8.12% to 75% of the total silver present in the solution. Transmission electron microscopy study of M. xanthus wet biomass after silver accumulation shows the sorption within the extracellular polysaccharide, on the cell wall, and in the cytoplasm. The presence of silver deposits in the cytoplasm indicates that at least two mechanisms are involved in silver sorption by this bacterium biomass. First, silver was bound to the cell surface and extracellular polysaccharide, and second, a silver intracellular deposition process took place. The higher amount of silver deposits in the extracellular polysaccharide, present abundantly in M. xanthus cells, explains the capacity of this bacterium to bind silver efficiently. The results obtained indicate that the removal of silver by M. xanthus from the diluted solutions could be used in recycling this valuable metal. One interesting observation of this investigation is the crystalline form, possibly as chlorargyrite, in which the silver deposits are found in the M. xanthus cells. 相似文献
16.
Hyo Won Suh Sun-Hee Hyun So-Hyun Kim Seok-Young Lee Hyung-Kyoon Choi 《Process Biochemistry》2013,48(10):1581-1586
In this study, the effects of methyl jasmonate (MJ) and silver nitrate (SN) treatment on metabolic profiles and yields of phytosterols such as campesterol, stigmasterol, and β-sitosterol in whole plant cultures of Lemna paucicostata were investigated using gas chromatography–mass spectrometry coupled with multivariate statistical analysis. The MJ and SN treatments retarded the growth of L. paucicostata plants, while they enhanced the yields of three phytosterols, compared to control. Higher yields of phytosterols were attained at day 28 compared to day 42. Moreover, stigmasterol yield was the highest at 0.85 mg/g from day 28 plants grown under MJ + SN co-treated culture. Among the various metabolites, the levels of palmitic and stearic acids, which might participate in a defense mechanism, were higher in the MJ + SN condition than in control. To determine the optimal timing of MJ + SN addition, MJ + SN was added on days 21, 28, and 35 after inoculation. The total yield and productivity of phytosterol reached maximum levels when the MJ + SN was added at day 35. The highest productivity of stigmasterol (6.08 mg/L) was also achieved when MJ + SN was added on day 35. 相似文献
17.
A green, simple, and effective approach was performed to synthesize potent silver nanoparticles (SNPs) using bacterial exopolysaccharide as both a reducing and stabilizing agent. The synthesized SNPs were characterized using UV-vis spectroscopy, transmission electron microscopy, energy dispersive X-ray analysis, X-ray diffraction, and Fourier-transform-infrared spectra analyses. The SNPs varied in shape and were multidispersed with a mean diameter of 10 nm ranging from 2 to 15 nm and were stable up to 2 months at room temperature. The antimicrobial activity of the SNPs was analyzed against bacterial and fungal pathogens using the agar well diffusion method. Dose dependent inhibition was observed for all bacterial pathogens. The multidrug resistant pathogens P. aeruginosa and K. pneumonia were found to be more susceptible to the SNPs than the food borne pathogen L. monocytogenes. The fungi Aspergillus spp. exhibited a maximum zone of inhibition compared to that of Penicillum spp. These results suggest that exopolysaccharide-stabilized SNPs can be used as an antimicrobial agent for various biomedical applications. 相似文献
18.
Abstract Germination tests were carried out on seeds from three Italian populations of Abies alba. Seed germinability was up to 38%. HgCl2, NaClO and plant preservative mixture were used as seed‐sterilising agents. Despite chemical treatments, Papulaspora rubida and Chaetomium globosum were isolated. The possible role of these fungi in the physiology of silver fir seed germination process was discussed. 相似文献
19.
The present study focused on the evaluation of antibacterial property of silver nanoparticles (AgNPs) synthesized using mango flower extract. The morphology of the synthesized AgNPs was observed under transmission electron microscopy and the particles have shown spherical shape in the range of 10–20 nm. X-ray powder diffraction analysis confirmed the crystalline nature of the AgNPs. The atomic percentage of the Ag element in the nanoparticles was about 7.58% which is greater than the other elements present in the sample. The AgNPs showed extensive lethal effect on both Gram-positive (Staphylococcus sp.) and Gram-negative (Klebsiella sp., Pantoea agglomerans, and Rahnella sp.) bacteria. The extensive lethal effect of AgNPs against clinically important pathogens demonstrated that the mango flower mediated AgNPs could be applied as potential antibacterial agent to control the bacterial population in the respective industries. 相似文献
20.
哀牢山国家级自然保护区南华片三种雉类春季取食地利用比较 总被引:1,自引:0,他引:1
探讨亲缘关系密切、营养关系相似的物种间的共存机制,是群落生态学的研究热点之一。研究结果有助于了解同域物种的资源利用特点和分化方式,对于地区生物多样性的保育工作亦具有指导意义。黑颈长尾雉(Syrmaticushumiae)、白鹇(Lophuranycthemera)和红喉山鹧鸪(Arborophilarufogularis)为哀牢山国家自然保护区南华片区同域分布的3种雉类,它们亲缘关系较近,食性相似。比较三者春季取食地18个生态因子生态位宽度和重叠指数,结果显示,黑颈长尾雉广适性(生态位宽度值>0·8)的取食地因子最少(1个),专一性(生态位宽度<0·8)因子最多(4个);白鹇居中(3个和2个);红喉山鹧鸪与黑颈长尾雉恰好相反(6个和0个)。黑颈长尾雉与白鹇生态位重叠指数≥0·5的因子数(5个)多于黑颈长尾雉与红喉山鹧鸪的(2个)和白鹇与红喉山鹧鸪的(4个);灌木层盖度、草本层盖度和种子密度的生态位重叠指数在3种雉类间均较大。单因素方差分析结果表明,3种雉类在坡向、乔木密度、草本层盖度、种子密度和土壤动物等5个因子均无差异;在距空旷地距离、距道路距离和灌木层盖度等3个因子均有差异;而其余因子则是在不同的两个物种之间有差异。主成分分析结果显示,黑颈长尾雉取食地前7个主成分的累计信息量达85·6%,白鹇的前6个达86·0%,红喉山鹧鸪的前5个达79·0%。影响这三种雉类取食地选择的因子主要集中于前3个主成分。3种雉类间取食地因子差异状态呈镶嵌分布,意味着种间生态位呈分化状态。各物种优先选择的因子组合不同,各因子的重要程度亦不一。 相似文献