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61.
This paper deals with the bond between steel reinforcement and recycled aggregate concrete, including Electric arc furnace (EAF) slag as full replacement of natural coarse aggregates. Pull-out tests were carried out according to RILEM standard on specimens made with six concrete mixtures, characterized by different w/c ratios and types of aggregates. Plain and ribbed steel reinforcement bars were used to observe the influence of steel roughness. Experimental bond-slip relationships were analyzed, and results show similar bond mechanisms between the reference and EAF concrete specimens. Significant bond strength enhancement is observed in concretes with low w/c ratio, when EAF slag is used as recycled coarse aggregate. Experimental results in terms of bond strength were also compared to analytical predictions, obtained with empirical formulations.  相似文献   
62.
A challenge in vector graphics is to define primitives that offer flexible manipulation of colour gradients. We propose a new primitive, called a shading curve, that supports explicit and local gradient control. This is achieved by associating shading profiles to each side of the curve. These shading profiles, which can be manually manipulated, represent the colour gradient out from their associated curves. Such explicit and local gradient control is challenging to achieve via the diffusion curve process, introduced in 2008, because it offers only implicit control of the colour gradient. We resolve this problem by using subdivision surfaces that are constructed from shading curves and their shading profiles.  相似文献   
63.
Dynamic behavior of continuous processes was numerically investigated for the catalytic hydrogenation of nitrile butadiene rubber, based on developed models, which took into account the coupling between kinetics and mass transfer. The evolution of hydrogenation reaction trajectories in both cases were analyzed. It is proposed that the coupling behavior between the catalytic hydrogenation and mass transfer was completely determined by the ability of the catalyst in activating hydrogen, carbon‐carbon double bond loading level and the relative capacity of reaction to mass transfer as well as the residence time in the reactor. Four dimensionless parameters were derived to characterize these aspects. The effects of operation conditions on the hydrogenation processes were investigated. The application of the ideal flow models to non‐ideal flows was in addition discussed. It is suggested that the optimal reactor for such a hydrogenation system would be a plug flow reactor with an instantaneous well‐mixing component in the inlet of it, and a reasonable approach to the proposed optimal reactor should be with the flow behavior of at least three continuous stirred tank reactors in series. Further research directions are suggested.  相似文献   
64.
In this study, the authors report on high‐quality amorphous indium–gallium–zinc oxide thin‐film transistors (TFTs) based on a single‐source dual‐layer concept processed at temperatures down to 150°C. The dual‐layer concept allows the precise control of local charge carrier densities by varying the O2/Ar gas ratio during sputtering for the bottom and top layers. Therefore, extensive annealing steps after the deposition can be avoided. In addition, the dual‐layer concept is more robust against variation of the oxygen flow in the deposition chamber. The charge carrier density in the TFT channel is namely adjusted by varying the thickness of the two layers whereby the oxygen concentration during deposition is switched only between no oxygen for the bottom layer and very high concentration for the top layer. The dual‐layer TFTs are more stable under bias conditions in comparison with single‐layer TFTs processed at low temperatures. Finally, the applicability of this dual‐layer concept in logic circuitry such as 19‐stage ring oscillators and a TFT backplane on polyethylene naphthalate foil containing a quarter video graphics array active‐matrix organic light‐emitting diode display demonstrator is proven.  相似文献   
65.
A lithium fluoride (LiF) crystal has been utilized as a new soft X-ray detector to image different biological samples at a high spatial resolution. This new type of image detector for X-ray microscopy has many interesting properties: high resolution (nanometer scale), permanent storage of images, the ability to clear the image and reuse the LiF crystal, and high contrast with greater dynamic range. Cells of the unicellular green algae Chlamydomonas dysosmos and Chlorella sorokiniana, and pollen grains of Olea europea have been used as biological materials for imaging. The biological samples were imaged on LiF crystals by using the soft X-ray contact microscopy and contact micro-radiography techniques. The laser plasma soft X-ray source was generated using a Nd:YAG/Glass laser focused on a solid target. The X-ray energy range for image acquisition was in the water-window spectral range for single shot contact microscopy of very thin biological samples (single cells) and around 1 keV for multishots microradiography. The main aim of this article is to highlight the possibility of using a LiF crystal as a detector for the biological imaging using soft X-ray radiation and to demonstrate its ability to visualize the microstructure within living cells.  相似文献   
66.
High contrast imaging of in vivo Chlorella sorokiniana cells with submicron spatial resolution was obtained with a contact water window X-ray microscopy technique using a point-like, laser-plasma produced, water-window X-ray radiation source, and LiF crystals as detectors. This novel type of X-ray imaging detectors is based on photoluminescence of stable electronic point defects, characterized by high intrinsic resolution. The fluorescence images obtained on LiF crystals exposed in single-shot experiments demonstrate the high sensitivity and dynamic range of this new detector. The powerful performances of LiF crystals allowed us to detect the exudates of Chlorella cells in their living medium and their spatial distribution in situ, without any special sample preparation.  相似文献   
67.
The modern low-pressure methanol synthesis catalysts are based on copper-containing systems such as Cu/ZnO/Al2O3 and Cu/ZnO/Cr2O3 with various compositions. These catalysts are also highly active for the low-temperature CO shift reaction. For both reactions the nature of the active sites is still an open question.  相似文献   
68.
ERCC1 is a key regulator of nucleotide excision repair (NER) pathway that repairs bulky DNA adducts, including intrastrand DNA adducts and interstrand crosslinks (ICLs). Overexpression of ERCC1 has been linked to increased DNA repair capacity and platinum resistance in solid tumors. Multiple single nucleotide polymorphisms (SNPs) have been detected in ERCC1 gene that may affect ERCC1 protein expression. Platinum-based treatment remains the cornerstone of urothelial cancer treatment. Given the expanding application of neoadjuvant and adjuvant chemotherapy in locally advanced bladder cancer, there is an emerging need for biomarkers that could distinguish potential responders to cisplatin treatment. Extensive research has been done regarding the prognostic and predictive role of ERCC1 gene expression and polymorphisms in bladder cancer. Moreover, novel compounds have been recently developed to target ERCC1 protein function in order to maximize sensitivity to cisplatin. We aim to review all the existing literature regarding the role of the ERCC1 gene in bladder cancer and address future perspectives for its clinical application.  相似文献   
69.
Circular RNAs (circRNAs) constitute a large class of non-coding RNAs characterized by a covalently closed circular structure. They originate during mRNA maturation through a modification of the splicing process and, according to the included sequences, are classified as Exonic, Intronic, or Exonic-Intronic. CircRNAs can act by sequestering microRNAs, by regulating the activity of specific proteins, and/or by being translated in functional peptides. There is emerging evidence indicating that dysregulation of circRNA expression is associated with pathological conditions, including cancer, neurological disorders, cardiovascular diseases, and diabetes. The aim of this review is to provide a comprehensive and updated view of the most abundant circRNAs expressed in pancreatic islet cells, some of which originating from key genes controlling the differentiation and the activity of insulin-secreting cells or from diabetes susceptibility genes. We will particularly focus on the role of a group of circRNAs that contribute to the regulation of β-cell functions and that display altered expression in the islets of rodent diabetes models and of type 2 diabetic patients. We will also provide an outlook of the unanswered questions regarding circRNA biology and discuss the potential role of circRNAs as biomarkers for β-cell demise and diabetes development.  相似文献   
70.
INTRODUCTION

The dynamic aspects of molecular structures at atomic resolution have become of increasing importance. The analysis of molecular motions of individual residues and structural domains of biomolecules is essential for an understanding of the functional aspects of biopolymers at the molecular level.  相似文献   
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