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991.
992.
The Impact of Zeta Potential and Physicochemical Properties of TiO2‐Based Nanocomposites on Their Biological Activity 下载免费PDF全文
Agnieszka Maria Jastrzębska Patrycja Kurtycz Andrzej Olszyna Ewa Karwowska Ewa Miaśkiewicz‐Pęska Monika Załęska‐Radziwiłł Nina Doskocz Dariusz Basiak 《International Journal of Applied Ceramic Technology》2015,12(6):1157-1173
The aim of this research was to observe the relationship between zeta potential, morphology, surface area, porosity, chemical composition, and ecotoxicity of nanocomposite powders such as Au/TiO2, Ag2O/TiO2, PdO/TiO2, Ag/TiO2/SiO2, Ag/N(C)TiO2, and SiO2/TiO2 from which Ag2O/TiO2, Ag/N(C)/TiO2, and Ag/TiO2/SiO2 were exhibiting good antimicrobial properties. It was observed, that nanomaterials characterized by similar morphology and zeta potential revealed the similar toxic behavior. The samples of higher agglomeration and higher zeta potential, especially Ag/TiO2/SiO2 xerogel and TiO2/SiO2 aerogel were generally less ecotoxic to water organisms and plants. They were also not genotoxic in concentrations up to 500 and 250 mg/L, respectively. 相似文献
993.
Different bacterial models for in vitro induction of non‐cavitated enamel caries‐like lesions: Microhardness and polarized light miscroscopy analyses 下载免费PDF全文
Priscila Hernández De Campos Mariane Emi Sanabe Jonas Almeida Rodrigues Danilo Antonio Duarte Maria Teresa Botti Rodrigues Santos Renata Oliveira Guaré cristiane Duque Adrian Lussi Michele Baffi Diniz 《Microscopy research and technique》2015,78(6):444-451
The aim of this study was to compare different bacterial models for in vitro induction of non‐cavitated enamel caries‐like lesions by microhardness and polarized light microscopy analyses. One hundred blocks of bovine enamel were randomly divided into four groups (n = 25) according to the bacterial model for caries induction: (A) Streptococcus mutans, (B) S. mutans and Lactobacillus acidophilus, (C) S. mutans and L. casei, and (D) S. mutans, L. acidophilus, and L. casei. Within each group, the blocks were randomly divided into five subgroups according to the duration of the period of caries induction (4–20 days). The enamel blocks were immersed in cariogenic solution containing the microorganisms, which was changed every 48 h. Groups C and D presented lower surface hardness values (SMH) and higher area of hardness loss (ΔS) after the cariogenic challenge than groups A and B (P < 0.05). As regards lesion depth, under polarized light microscopy, group A presented significantly lower values, and groups C and D the highest values. Group B showed a higher value than group A (P < 0.05). Groups A and B exhibited subsurface caries lesions after all treatment durations, while groups C and D presented erosion‐type lesions with surface softening. The model using S. mutans, whether or not it was associated with L. acidophilus, was less aggressive and may be used for the induction of non‐cavitated enamel caries‐like lesions. The optimal period for inducing caries‐like lesions was 8 days. Microsc. Res. Tech. 78:444–451, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
994.
Tract‐tracing study of the extrabulbar Olfactory projections in the brain of some teleosts 下载免费PDF全文
Biagio D'aniello Luciano Luongo Rakesh K. Rastogi Maria Di Meglio Claudia Pinelli 《Microscopy research and technique》2015,78(4):268-276
The extrabulbar olfactory projections (EBOP) is a collection of nerve fibers that originate from primary olfactory receptor neurons. These fibers penetrate into the brain, bypassing the olfactory bulbs (OBs). While the presence of an EBOP has been well established in teleosts, here we morphologically characterize the EBOP structure in four species each with a different morphological relationship of OB with the ventral telencephalic area. Tract‐tracing methods (carbocyanine DiI/DIA and biocytin) were used. FMRFamide immunoreactive nervus terminalis (NT) components were also visualized to define any neuroanatomical relationship between the NT and EBOP. Unilateral DiI/DiA application to the olfactory chamber stained the entire olfactory epithelium, olfactory nerve fibers, and ipsilateral olfactory bulb. Labeled primary olfactory fibers running ventromedially as extrabulbar primary olfactory projections reached various regions of the secondary prosencephalon. Only in Moenkhausia sanctaefilomenae (no olfactory peduncle) did lipophilic tracer‐labeled fibers reach the ipsilateral mesencephalon. The combination of tracing techniques and FMRFamide immunohistochemistry revealed a substantial overlap of the label along the olfactory pathways as well as in the anterior secondary prosencephalon. However, FMRFamide immunoreactivity was never colocalized in the same cellular or fiber component as visualized using tracer molecules. Our results showed a certain uniformity in the neuroanatomy and extension of EBOP in all four species, independent of the pedunculate feature of the OBs. The present study also provided additional evidence to support the view that EBOP and FMRFamide immunoreactive components of the NT are separate anatomical entities. Microsc. Res. Tech. 78:268–276, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
995.
High concentration of phosphorus is a distinctive feature of myelin. An X‐Ray elemental microanalysis study using freeze‐fracture scanning electron microscopy of rat sciatic nerve 下载免费PDF全文
We have used rat sciatic nerves submitted to freezing and freeze‐fracture to determine the elemental composition of small domains of the peripheral nerve studied at high resolution by scanning electron microscopy. We found that myelin of Schwann cells is unique in its high content in phosphorus (P) that was more than 10 times higher than P measured in any other cells. This high concentration in P makes myelin chemistry suitable of monitoring at the subcellular level using the herein described methodology. Microsc. Res. Tech. 78:537–539, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
996.
当代法国风景园林行业中的女性 总被引:1,自引:0,他引:1
女性一直在风景园林行业发展中占有一席之地。欧洲以及法国的主要风景园林协会、联盟,都有女性积极参与,虽然并未官居要职,但数量上占有较大比例。对法国风景园林教育研究、设计实践的发展,女性都起到了重要的推动作用。对具有代表性的法国女风景园林师做了梳理与介绍,总结法国当代风景园林行业内女性的发展状况特征。未来,女性将在风景园林领域内持续发挥重要作用。 相似文献
997.
Silvia Cammarano Valerio Roberto Maria Lo Verso Chiara Aghemo 《Building Research & Information》2015,43(2):222-237
Results are presented from a parametric study that assessed the amount of daylight in rooms with different architectural features: the orientation, window size and visible glazing transmittance, room depth, external obstruction angle and site. Annual lighting simulations were run in order to understand how the daylight availability within a space changes as a function of the architectural features. A sub-dataset of the full result database is examined in detail for north- and south-facing rooms in Turin, north-west Italy, with a visible glazing transmittance of 70%. Each feature is analysed for its influence on the daylighting conditions. A simple graphical tool is presented to promote an easier reading of the results. This was developed to provide a synthesis of information to the design team. It shows the influence of preliminary design solutions on the amount of indoor daylight. This allows a design team to assess indoor daylighting from the earliest design phases onwards and to determine which combinations of architectural features are able to provide high, acceptable or low daylight levels within a room. 相似文献
998.
Statistical Regularization for Identification of Structural Parameters and External Loadings Using State Space Models 下载免费PDF全文
Hao Sun Dongming Feng Yang Liu Maria Q. Feng 《Computer-Aided Civil and Infrastructure Engineering》2015,30(11):843-858
A novel numerical approach is presented, in the time domain, to simultaneously identify structural parameters and unmeasured input loadings using incomplete output measurement only. The identification problem is formulated as an optimization process, wherein the objective function is defined as the discrepancy between the measured and the predicted data, and is solved by a damped Gauss‐Newton method. Because the proposed algorithm is a time domain technique, forward analyses are required to obtain predicted system responses so as to compute the discrepancy. Therefore, we propose an input force estimation scheme in the identification process to complete the task of input‐output forward analyses, for the case of output‐only measurement. The relationship between the unknown input loadings and the output measurement is established through a state space model, which basically formulates an ill‐posed least squares problem. A statistical Bayesian inference‐based regularization technique is presented to solve such a least squares problem. Finally, the proposed approach is illustrated by both numerical and experimental examples using output‐only measurements of either acceleration or strain time histories. The results clearly show the robustness and the applicability of the proposed algorithm to simultaneously identify structural parameters and unmeasured input loadings with a high accuracy. 相似文献
999.
Giovanni Maria Montuori Monica Fadda Gianpaolo Perrella Elena Mele 《The Structural Design of Tall and Special Buildings》2015,24(15):912-940
This paper provides a first insight on tube configurations based on the hexagonal shape (hexagrid) for tall buildings. The idea is to investigate the mechanical properties of hexagrid to assess their applicability in tall buildings and to compare their potential efficiency to the more popular diagrid systems. For the above purposes, a general homogenization approach has been established for dealing with any structural patterns, and a methodology for characterizing the structural patterns from the mechanical point of view has been developed and specified for hexagrids and diagrids. Then on the basis of a simple stiffness criterion, a design procedure has been proposed and applied to a tall building case study, and several structural solutions (both hexagrids and diagrids) have been designed and assessed by varying the major geometrical parameters of the patterns. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Yolandi C. Montgomery Walter W. Focke Maria Atanasova Olinto DelFabbro Cheryl Kelly 《Propellants, Explosives, Pyrotechnics》2016,41(5):919-925
The binary Mn+Sb2O3 pyrotechnic composition was investigated for mining detonator time delay applications. EKVI thermodynamic modelling predicted two maxima in the adiabatic reaction temperature. The local maximum, at a manganese fuel content of ca. 36 wt‐%, corresponds to a pure thermite‐type redox reaction: 3 Mn+Sb2O3→3 MnO+2Sb. The overall maximum in the adiabatic reaction temperature (ca. 1640 K), at the fuel‐rich composition of 49 wt‐% Mn, is consistent with the reaction 5 Mn+Sb2O3→3 MnO+2 MnSb, i.e. a combination of the standard thermite with an additional exothermic intermetallic reaction. XRD analysis of combustion residues confirmed the formation of MnSb and Mn2Sb for fuel‐rich compositions. Burn rates were measured using delay elements assembled into commercial detonators. The d50 particle sizes were 23.4 and 0.92 μm for the Mn fuel and Sb2O3 oxidant powders, respectively. The delay elements comprised rolled lead tubes with a length of 44 mm and an outer diameter of 6.4 mm. The rolling action compacted the pyrotechnic compositions to 74 ± 2 % theoretical maximum density. The burning rate increased linearly from 4.2 to 9.4 mm s−1 over the composition range 25–50 wt‐% Mn. 相似文献