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Sample records for multiple-instance learning mil

  1. Multiple-instance learning as a classifier combining problem

    Li, Yan; Tax, David M. J.; Duin, Robert P. W.

    2013-01-01

    In multiple-instance learning (MIL), an object is represented as a bag consisting of a set of feature vectors called instances. In the training set, the labels of bags are given, while the uncertainty comes from the unknown labels of instances in the bags. In this paper, we study MIL with the ass...

  2. Dissimilarity-based multiple instance learning

    Sørensen, Lauge; Loog, Marco; Tax, David M. J.

    2010-01-01

    In this paper, we propose to solve multiple instance learning problems using a dissimilarity representation of the objects. Once the dissimilarity space has been constructed, the problem is turned into a standard supervised learning problem that can be solved with a general purpose supervised cla...... between distributions of within- and between set point distances, thereby taking relations within and between sets into account. Experiments on five publicly available data sets show competitive performance in terms of classification accuracy compared to previously published results....

  3. Multiple instance learning tracking method with local sparse representation

    Xie, Chengjun

    2013-10-01

    When objects undergo large pose change, illumination variation or partial occlusion, most existed visual tracking algorithms tend to drift away from targets and even fail in tracking them. To address this issue, in this study, the authors propose an online algorithm by combining multiple instance learning (MIL) and local sparse representation for tracking an object in a video system. The key idea in our method is to model the appearance of an object by local sparse codes that can be formed as training data for the MIL framework. First, local image patches of a target object are represented as sparse codes with an overcomplete dictionary, where the adaptive representation can be helpful in overcoming partial occlusion in object tracking. Then MIL learns the sparse codes by a classifier to discriminate the target from the background. Finally, results from the trained classifier are input into a particle filter framework to sequentially estimate the target state over time in visual tracking. In addition, to decrease the visual drift because of the accumulative errors when updating the dictionary and classifier, a two-step object tracking method combining a static MIL classifier with a dynamical MIL classifier is proposed. Experiments on some publicly available benchmarks of video sequences show that our proposed tracker is more robust and effective than others. © The Institution of Engineering and Technology 2013.

  4. On Combining Multiple-Instance Learning and Active Learning for Computer-Aided Detection of Tuberculosis

    Melendez Rodriguez, J.C.; Ginneken, B. van; Maduskar, P.; Philipsen, R.H.H.M.; Ayles, H.; Sanchez, C.I.

    2016-01-01

    The major advantage of multiple-instance learning (MIL) applied to a computer-aided detection (CAD) system is that it allows optimizing the latter with case-level labels instead of accurate lesion outlines as traditionally required for a supervised approach. As shown in previous work, a MIL-based

  5. Parallel multiple instance learning for extremely large histopathology image analysis.

    Xu, Yan; Li, Yeshu; Shen, Zhengyang; Wu, Ziwei; Gao, Teng; Fan, Yubo; Lai, Maode; Chang, Eric I-Chao

    2017-08-03

    Histopathology images are critical for medical diagnosis, e.g., cancer and its treatment. A standard histopathology slice can be easily scanned at a high resolution of, say, 200,000×200,000 pixels. These high resolution images can make most existing imaging processing tools infeasible or less effective when operated on a single machine with limited memory, disk space and computing power. In this paper, we propose an algorithm tackling this new emerging "big data" problem utilizing parallel computing on High-Performance-Computing (HPC) clusters. Experimental results on a large-scale data set (1318 images at a scale of 10 billion pixels each) demonstrate the efficiency and effectiveness of the proposed algorithm for low-latency real-time applications. The framework proposed an effective and efficient system for extremely large histopathology image analysis. It is based on the multiple instance learning formulation for weakly-supervised learning for image classification, segmentation and clustering. When a max-margin concept is adopted for different clusters, we obtain further improvement in clustering performance.

  6. Multiple instance learning tracking method with local sparse representation

    Xie, Chengjun; Tan, Jieqing; Chen, Peng; Zhang, Jie; Helg, Lei

    2013-01-01

    as training data for the MIL framework. First, local image patches of a target object are represented as sparse codes with an overcomplete dictionary, where the adaptive representation can be helpful in overcoming partial occlusion in object tracking. Then MIL

  7. Prediction of Ionizing Radiation Resistance in Bacteria Using a Multiple Instance Learning Model.

    Aridhi, Sabeur; Sghaier, Haïtham; Zoghlami, Manel; Maddouri, Mondher; Nguifo, Engelbert Mephu

    2016-01-01

    Ionizing-radiation-resistant bacteria (IRRB) are important in biotechnology. In this context, in silico methods of phenotypic prediction and genotype-phenotype relationship discovery are limited. In this work, we analyzed basal DNA repair proteins of most known proteome sequences of IRRB and ionizing-radiation-sensitive bacteria (IRSB) in order to learn a classifier that correctly predicts this bacterial phenotype. We formulated the problem of predicting bacterial ionizing radiation resistance (IRR) as a multiple-instance learning (MIL) problem, and we proposed a novel approach for this purpose. We provide a MIL-based prediction system that classifies a bacterium to either IRRB or IRSB. The experimental results of the proposed system are satisfactory with 91.5% of successful predictions.

  8. Automated detection of age-related macular degeneration in OCT images using multiple instance learning

    Sun, Weiwei; Liu, Xiaoming; Yang, Zhou

    2017-07-01

    Age-related Macular Degeneration (AMD) is a kind of macular disease which mostly occurs in old people,and it may cause decreased vision or even lead to permanent blindness. Drusen is an important clinical indicator for AMD which can help doctor diagnose disease and decide the strategy of treatment. Optical Coherence Tomography (OCT) is widely used in the diagnosis of ophthalmic diseases, include AMD. In this paper, we propose a classification method based on Multiple Instance Learning (MIL) to detect AMD. Drusen can exist in a few slices of OCT images, and MIL is utilized in our method. We divided the method into two phases: training phase and testing phase. We train the initial features and clustered to create a codebook, and employ the trained classifier in the test set. Experiment results show that our method achieved high accuracy and effectiveness.

  9. Seeing is believing: video classification for computed tomographic colonography using multiple-instance learning.

    Wang, Shijun; McKenna, Matthew T; Nguyen, Tan B; Burns, Joseph E; Petrick, Nicholas; Sahiner, Berkman; Summers, Ronald M

    2012-05-01

    In this paper, we present development and testing results for a novel colonic polyp classification method for use as part of a computed tomographic colonography (CTC) computer-aided detection (CAD) system. Inspired by the interpretative methodology of radiologists using 3-D fly-through mode in CTC reading, we have developed an algorithm which utilizes sequences of images (referred to here as videos) for classification of CAD marks. For each CAD mark, we created a video composed of a series of intraluminal, volume-rendered images visualizing the detection from multiple viewpoints. We then framed the video classification question as a multiple-instance learning (MIL) problem. Since a positive (negative) bag may contain negative (positive) instances, which in our case depends on the viewing angles and camera distance to the target, we developed a novel MIL paradigm to accommodate this class of problems. We solved the new MIL problem by maximizing a L2-norm soft margin using semidefinite programming, which can optimize relevant parameters automatically. We tested our method by analyzing a CTC data set obtained from 50 patients from three medical centers. Our proposed method showed significantly better performance compared with several traditional MIL methods.

  10. Event recognition in personal photo collections via multiple instance learning-based classification of multiple images

    Ahmad, Kashif; Conci, Nicola; Boato, Giulia; De Natale, Francesco G. B.

    2017-11-01

    Over the last few years, a rapid growth has been witnessed in the number of digital photos produced per year. This rapid process poses challenges in the organization and management of multimedia collections, and one viable solution consists of arranging the media on the basis of the underlying events. However, album-level annotation and the presence of irrelevant pictures in photo collections make event-based organization of personal photo albums a more challenging task. To tackle these challenges, in contrast to conventional approaches relying on supervised learning, we propose a pipeline for event recognition in personal photo collections relying on a multiple instance-learning (MIL) strategy. MIL is a modified form of supervised learning and fits well for such applications with weakly labeled data. The experimental evaluation of the proposed approach is carried out on two large-scale datasets including a self-collected and a benchmark dataset. On both, our approach significantly outperforms the existing state-of-the-art.

  11. Multiple-instance learning for computer-aided detection of tuberculosis

    Melendez, J.; Sánchez, C. I.; Philipsen, R. H. H. M.; Maduskar, P.; van Ginneken, B.

    2014-03-01

    Detection of tuberculosis (TB) on chest radiographs (CXRs) is a hard problem. Therefore, to help radiologists or even take their place when they are not available, computer-aided detection (CAD) systems are being developed. In order to reach a performance comparable to that of human experts, the pattern recognition algorithms of these systems are typically trained on large CXR databases that have been manually annotated to indicate the abnormal lung regions. However, manually outlining those regions constitutes a time-consuming process that, besides, is prone to inconsistencies and errors introduced by interobserver variability and the absence of an external reference standard. In this paper, we investigate an alternative pattern classi cation method, namely multiple-instance learning (MIL), that does not require such detailed information for a CAD system to be trained. We have applied this alternative approach to a CAD system aimed at detecting textural lesions associated with TB. Only the case (or image) condition (normal or abnormal) was provided in the training stage. We compared the resulting performance with those achieved by several variations of a conventional system trained with detailed annotations. A database of 917 CXRs was constructed for experimentation. It was divided into two roughly equal parts that were used as training and test sets. The area under the receiver operating characteristic curve was utilized as a performance measure. Our experiments show that, by applying the investigated MIL approach, comparable results as with the aforementioned conventional systems are obtained in most cases, without requiring condition information at the lesion level.

  12. Mass detection in digital breast tomosynthesis data using convolutional neural networks and multiple instance learning.

    Yousefi, Mina; Krzyżak, Adam; Suen, Ching Y

    2018-05-01

    Digital breast tomosynthesis (DBT) was developed in the field of breast cancer screening as a new tomographic technique to minimize the limitations of conventional digital mammography breast screening methods. A computer-aided detection (CAD) framework for mass detection in DBT has been developed and is described in this paper. The proposed framework operates on a set of two-dimensional (2D) slices. With plane-to-plane analysis on corresponding 2D slices from each DBT, it automatically learns complex patterns of 2D slices through a deep convolutional neural network (DCNN). It then applies multiple instance learning (MIL) with a randomized trees approach to classify DBT images based on extracted information from 2D slices. This CAD framework was developed and evaluated using 5040 2D image slices derived from 87 DBT volumes. The empirical results demonstrate that this proposed CAD framework achieves much better performance than CAD systems that use hand-crafted features and deep cardinality-restricted Bolzmann machines to detect masses in DBTs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Gaussian Multiple Instance Learning Approach for Mapping the Slums of the World Using Very High Resolution Imagery

    Vatsavai, Raju [ORNL

    2013-01-01

    In this paper, we present a computationally efficient algo- rithm based on multiple instance learning for mapping infor- mal settlements (slums) using very high-resolution remote sensing imagery. From remote sensing perspective, infor- mal settlements share unique spatial characteristics that dis- tinguish them from other urban structures like industrial, commercial, and formal residential settlements. However, regular pattern recognition and machine learning methods, which are predominantly single-instance or per-pixel classi- fiers, often fail to accurately map the informal settlements as they do not capture the complex spatial patterns. To overcome these limitations we employed a multiple instance based machine learning approach, where groups of contigu- ous pixels (image patches) are modeled as generated by a Gaussian distribution. We have conducted several experi- ments on very high-resolution satellite imagery, represent- ing four unique geographic regions across the world. Our method showed consistent improvement in accurately iden- tifying informal settlements.

  14. HyDR-MI : A hybrid algorithm to reduce dimensionality in multiple instance learning

    Zafra, A.; Pechenizkiy, M.; Ventura, S.

    2013-01-01

    Feature selection techniques have been successfully applied in many applications for making supervised learning more effective and efficient. These techniques have been widely used and studied in traditional supervised learning settings, where each instance is expected to have a label. In multiple

  15. Feature selection is the ReliefF for multiple instance learning

    Zafra, A.; Pechenizkiy, M.; Ventura, S.

    2010-01-01

    Dimensionality reduction and feature selection in particular are known to be of a great help for making supervised learning more effective and efficient. Many different feature selection techniques have been proposed for the traditional settings, where each instance is expected to have a label. In

  16. Automated gastric cancer diagnosis on H&E-stained sections; ltraining a classifier on a large scale with multiple instance machine learning

    Cosatto, Eric; Laquerre, Pierre-Francois; Malon, Christopher; Graf, Hans-Peter; Saito, Akira; Kiyuna, Tomoharu; Marugame, Atsushi; Kamijo, Ken'ichi

    2013-03-01

    We present a system that detects cancer on slides of gastric tissue sections stained with hematoxylin and eosin (H&E). At its heart is a classi er trained using the semi-supervised multi-instance learning framework (MIL) where each tissue is represented by a set of regions-of-interest (ROI) and a single label. Such labels are readily obtained because pathologists diagnose each tissue independently as part of the normal clinical work ow. From a large dataset of over 26K gastric tissue sections from over 12K patients obtained from a clinical load spanning several months, we train a MIL classi er on a patient-level partition of the dataset (2/3 of the patients) and obtain a very high performance of 96% (AUC), tested on the remaining 1/3 never-seen before patients (over 8K tissues). We show this level of performance to match the more costly supervised approach where individual ROIs need to be labeled manually. The large amount of data used to train this system gives us con dence in its robustness and that it can be safely used in a clinical setting. We demonstrate how it can improve the clinical work ow when used for pre-screening or quality control. For pre-screening, the system can diagnose 47% of the tissues with a very low likelihood (cancers, thus halving the clinicians' caseload. For quality control, compared to random rechecking of 33% of the cases, the system achieves a three-fold increase in the likelihood of catching cancers missed by pathologists. The system is currently in regular use at independent pathology labs in Japan where it is used to double-check clinician's diagnoses. At the end of 2012 it will have analyzed over 80,000 slides of gastric and colorectal samples (200,000 tissues).

  17. A Fisher Kernel Approach for Multiple Instance Based Object Retrieval in Video Surveillance

    MIRONICA, I.

    2015-11-01

    Full Text Available This paper presents an automated surveillance system that exploits the Fisher Kernel representation in the context of multiple-instance object retrieval task. The proposed algorithm has the main purpose of tracking a list of persons in several video sources, using only few training examples. In the first step, the Fisher Kernel representation describes a set of features as the derivative with respect to the log-likelihood of the generative probability distribution that models the feature distribution. Then, we learn the generative probability distribution over all features extracted from a reduced set of relevant frames. The proposed approach shows significant improvements and we demonstrate that Fisher kernels are well suited for this task. We demonstrate the generality of our approach in terms of features by conducting an extensive evaluation with a broad range of keypoints features. Also, we evaluate our method on two standard video surveillance datasets attaining superior results comparing to state-of-the-art object recognition algorithms.

  18. Salience Assignment for Multiple-Instance Data and Its Application to Crop Yield Prediction

    Wagstaff, Kiri L.; Lane, Terran

    2010-01-01

    An algorithm was developed to generate crop yield predictions from orbital remote sensing observations, by analyzing thousands of pixels per county and the associated historical crop yield data for those counties. The algorithm determines which pixels contain which crop. Since each known yield value is associated with thousands of individual pixels, this is a multiple instance learning problem. Because individual crop growth is related to the resulting yield, this relationship has been leveraged to identify pixels that are individually related to corn, wheat, cotton, and soybean yield. Those that have the strongest relationship to a given crop s yield values are most likely to contain fields with that crop. Remote sensing time series data (a new observation every 8 days) was examined for each pixel, which contains information for that pixel s growth curve, peak greenness, and other relevant features. An alternating-projection (AP) technique was used to first estimate the "salience" of each pixel, with respect to the given target (crop yield), and then those estimates were used to build a regression model that relates input data (remote sensing observations) to the target. This is achieved by constructing an exemplar for each crop in each county that is a weighted average of all the pixels within the county; the pixels are weighted according to the salience values. The new regression model estimate then informs the next estimate of the salience values. By iterating between these two steps, the algorithm converges to a stable estimate of both the salience of each pixel and the regression model. The salience values indicate which pixels are most relevant to each crop under consideration.

  19. Retrieving clinically relevant diabetic retinopathy images using a multi-class multiple-instance framework

    Chandakkar, Parag S.; Venkatesan, Ragav; Li, Baoxin

    2013-02-01

    Diabetic retinopathy (DR) is a vision-threatening complication from diabetes mellitus, a medical condition that is rising globally. Unfortunately, many patients are unaware of this complication because of absence of symptoms. Regular screening of DR is necessary to detect the condition for timely treatment. Content-based image retrieval, using archived and diagnosed fundus (retinal) camera DR images can improve screening efficiency of DR. This content-based image retrieval study focuses on two DR clinical findings, microaneurysm and neovascularization, which are clinical signs of non-proliferative and proliferative diabetic retinopathy. The authors propose a multi-class multiple-instance image retrieval framework which deploys a modified color correlogram and statistics of steerable Gaussian Filter responses, for retrieving clinically relevant images from a database of DR fundus image database.

  20. Media and Information Literacy (MIL) in journalistic learning: strategies for accurately engaging with information and reporting news

    Inayatillah, F.

    2018-01-01

    In the era of digital technology, there is abundant information from various sources. This ease of access needs to be accompanied by the ability to engage with the information wisely. Thus, information and media literacy is required. From the results of preliminary observations, it was found that the students of Universitas Negeri Surabaya, whose major is Indonesian Literature, and they take journalistic course lack of the skill of media and information literacy (MIL). Therefore, they need to be equipped with MIL. The method used is descriptive qualitative, which includes data collection, data analysis, and presentation of data analysis. Observation and documentation techniques were used to obtain data of MIL’s impact on journalistic learning for students. This study aims at describing the important role of MIL for students of journalistic and its impact on journalistic learning for students of Indonesian literature batch 2014. The results of this research indicate that journalistic is a science that is essential for students because it affects how a person perceives news report. Through the reinforcement of the course, students can avoid a hoax. MIL-based journalistic learning makes students will be more skillful at absorbing, processing, and presenting information accurately. The subject influences students in engaging with information so that they can report news credibly.

  1. Chi-squared: A simpler evaluation function for multiple-instance learning

    McGovern, Amy; Jensen, David

    2003-01-01

    ...) but finds the best concept using the chi-square statistic. This approach is simpler than diverse density and allows us to search more extensively by using properties of the contingency table to prune in a guaranteed manner...

  2. Petits mils

    cinq fois moins d'eau que le riz ? Note d'analyse ... dont une teneur élevée en micronutriments et en fibres alimentaires et un indice glycémique faible. ... Malgré les qualités nutritionnelles supérieures et la résilience au climat des petits mils, ...

  3. Multiple Instance Fuzzy Inference

    2015-12-02

    Fashion models 5.19 14 Sunset scenes 3.52 15 Cars 4.93 16 Waterfalls 2.56 17 Antique furniture 2.30 18 Battle ships 4.32 19 Skiing 3.34 20 Desserts ...1000, in addition 10% of the Desserts category images were confused with Beach and 20.9% of Mountains and glaciers images were misclassified as

  4. Multi-instance learning based on instance consistency for image retrieval

    Zhang, Miao; Wu, Zhize; Wan, Shouhong; Yue, Lihua; Yin, Bangjie

    2017-07-01

    Multiple-instance learning (MIL) has been successfully utilized in image retrieval. Existing approaches cannot select positive instances correctly from positive bags which may result in a low accuracy. In this paper, we propose a new image retrieval approach called multiple instance learning based on instance-consistency (MILIC) to mitigate such issue. First, we select potential positive instances effectively in each positive bag by ranking instance-consistency (IC) values of instances. Then, we design a feature representation scheme, which can represent the relationship among bags and instances, based on potential positive instances to convert a bag into a single instance. Finally, we can use a standard single-instance learning strategy, such as the support vector machine, for performing object-based image retrieval. Experimental results on two challenging data sets show the effectiveness of our proposal in terms of accuracy and run time.

  5. Por mil devaluados pesos

    Annie Rodríguez Collázos

    2013-03-01

    Full Text Available El estudio de lo popular y lo urbano hasta ahora se ha centrado en el comportamiento y en algunas relaciones de los habitantes con su entorno. “Por mil devaluados pesos. Publicidad popular y urbana”, pretende explorar las formas de publicidad, dispersas en diferentes espacios populares y urbanos en Bogotá, identificando esquemas y formas características de sus propios códigos comunicativos; se centran en un objeto de estudio consistente en las estrategias publicitarias y los códigos comunicativos en los mensajes publicitarios populares en las subculturas de San Victorino, 7 de Agosto y Sanandresito de San José.

  6. Navy.mil - Photo Galleries

    Personnel Command (NPC) Navy SAPR Navy EEO Inclusion And Diversity Navy Standard Integrated Personnel System (OPSEC) Navy Trademarks Military One Source USA.gov U.S. Office of Special Counsel Social Media Directory Links Navy Reserve Navy.mil Underway Navy Personnel Command (NPC) Navy SAPR Navy EEO Inclusion And

  7. Synthesis and Characterization Studies of MIL-101

    Emine Kaya EKİNCİ

    2017-12-01

    Full Text Available MIL-101 is a kind of Metal Organic Frameworks (MOFs, which have attracted much attention in the past decade due to its promising application in chemical industries. MIL-101 is also known as “Porous Chromium Terephthalate”. It has very high surface area and pore volume. MIL-101 exhibits exceptional stability against moisture and other chemicals and is composed of coordinately unsaturated Cr- sites with high concentration available for catalysis and adsorption. MIL-101 was synthesized by hydrothermal method and characterized by XRD, nitrogen adsorption and desorption analyses and SEM. XRD patterns show the presence of MIL-101’s crystal structure with high surface area (~2400 m2/g. Nitrogen adsorption-desorption analyzes showed that the material exhibited mesoporous material behavior.

  8. As milícias nacionais

    Jeanne Berrance de Castro

    1968-03-01

    Full Text Available As milícias nacionais — herança ideológica do século XVIII —tiveram na milícia norte-americana e nas Guardas Nacionais francesa e também brasileira expressivos exemplos dessas fôrças paramilitares. O conceito da "nação em armas", institucionalizado, possibilitou ao poder civil o contrôle militar, auxilado de outro lado pela descen-tralização dessas milícias nacionais que, com isso, suplantaram as fôrças militares regulares.

  9. Highly efficient capture of iodine by Cu/MIL-101

    Qi, Bingbing; Liu, Ying; Zheng, Tao; Gao, Qianhong; Yan, Xuewu; Jiao, Yan; Yang, Yi

    2018-02-01

    In order to improve the uptake capacity of MIL-101 for iodine, Cu nanoparticles doped MIL-101 were successfully synthesized through a facile method. The obtained Cu/MIL-101 was characterized by SEM, XRD, EDS, TEM, IR, TGA and BET to examine the chemical and thermal stabilities. The capture experiments for the adsorbents showed that the capture capacity of Cu/MIL-101 for volatile iodine is 342 wt%, which is higher than that of pure MIL-101. An I2 uptake of 342 wt% is the highest value reported among metal-organic frameworks. Furthermore, Cu/MIL-101 has a cycle ratio of 95% after three cycles and exhibits a better cyclicity than pure MIL-101. Meanwhile, Cu/MIL-101 shows an excellent reversible adsorption of iodine in solution.

  10. Metal organic framework MIL-101(Cr) for dehydration reactions

    Porous chromium terephthalate MIL-101 (Cr-MIL-101) has been prepared by direct method under hydrothermal conditions and characterized using X-ray diffraction, N2 sorption, TGA and FT-IR. The nitrogen adsorption-desorption isotherm shows that the Cr-MIL-101 possesses BET specific surface area of 2563 m2/g.

  11. 1 mil gold bond wire study.

    Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W.; Rutherford, Brian Milne

    2013-05-01

    In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, the gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.

  12. MIL-53(Fe), MIL-101, and SBA-15 porous materials: potential platforms for drug delivery.

    Gordon, Jeff; Kazemian, Hossein; Rohani, Sohrab

    2015-02-01

    Conventional drug administration suffers from several drawbacks, including a lack of specificity for diseased tissue, the necessity of large and frequent doses, and adverse side effects. Great effort is currently being devoted to developing nanoparticle-based therapeutics capable of prolonging drug administration and providing better control. Here we demonstrate the use of flexible microporous MIL-53(Fe) and mesoporous MIL-101 and SBA-15 as matrices for the adsorption and in vitro drug delivery of acetaminophen, progesterone, and stavudine. A drug loading of 20 wt.% was achieved for each of the nanomaterials using an incipient wetness impregnation procedure. BET, DSC, and XRPD analyses indicated that the entire loaded amount of each of the model drugs had successfully been incorporated within the mesoporous channels of both MIL-101 and SBA-15. DSC analysis evidenced that a portion of each of the model drugs had deposited onto the outer surface of MIL-53(Fe) particles; however, the portion of each drug that had incorporated within the microporous channels was slowly delivered in a diffusion-controlled process, which occurred over a period of up to six days for acetaminophen. These results demonstrate the unique ability of MIL-53(Fe) to adapt its porosity and optimize drug-matrix interactions. Owing to its larger pore diameters and weaker host-guest interactions, MIL-101 release times were shorter, yet still prolonged, as evidenced by the complete release of stavudine after five days. Complete release of each of the drugs from SBA-15 occurred very quickly as a result of rapid drug dissolution and diffusion out of the mesopores. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Late Bombardment of the Lunar Highlands Recorded in MIL 090034, MIL 090036 and MIL 090070 Lunar Meteorites

    Park, J.; Nyquist, L. E.; Shih, C.-Y.; Herzog, G. F.; Yamaguchi, A.; Shirai, N.; Ebihara, M.; Lindsay, F. N.; Delaney, J.; Turrin, B.; hide

    2013-01-01

    The Kaguya mission detected small but widespread outcrops of nearly pure ferroan anorthosite in and around large impact basins on the Moon. Along with certain lunar rocks, highly feldspathic lunar meteorites such as MIL 090034 (M34), 090036 (M36), and 090070 (M70) may provide samples of this material. We have measured the Ar-40/Ar-39 release patterns and cosmogenic Ar-38 concentrations of several small (<200 microg) samples separated from M34,36, and 70. From petrographic observations concluded that "some of the clasts and grains experienced generations of modifications," a conclusion that we examine in light of our data.

  14. The removal of bisphenol A from aqueous solutions by MIL-53(Al) and mesostructured MIL-53(Al).

    Zhou, Meimei; Wu, Yi-Nan; Qiao, Junlian; Zhang, Jing; McDonald, Amanda; Li, Guangtao; Li, Fengting

    2013-09-01

    In this work, metal-organic framework MIL-53(Al){Al(OH)[O2C-C6H4-CO2]} and MIL-53(Al)-F127{Al(OH)[O2C-C6H4-CO2]} were synthesized and used as sorbents to remove bisphenol A (BPA) from aqueous system. The sorption kinetics data of BPA were found to be in agreement with the pseudo-second-order model. The equilibrium sorption amounts of BPA on MIL-53(Al) and MIL-53(Al)-F127 reached 329.2±16.5 and 472.7±23.6 mg g(-1), respectively, far more than that of commercial activated carbons (ranging from 129.6 to 263.1 mg g(-1)). Both MIL-53(Al) and MIL-53(Al)-F127 could remove BPA fast from aqueous solutions, and the required contact time to reach equilibrium was approximately 90 min for MIL-53(Al) and 30 min for MIL-53(Al)-F127, respectively. The optimum pH levels for the removal of BPA using MIL-53 (Al) and MIL-53(Al)-F127 were 4 and 6 separately. The optimum temperature for the sorption behavior of BPA on the two sorbents was 20 °C. The results performed show that the resulting products, as one kind of MOFs, can be regarded as a new class of sorbents for water treatment and could find great applications in the fields of environmental water pollution control and resources reuse. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Una imatge val per mil paraules

    Jaume Cabré

    1999-11-01

    Full Text Available Una vegada hi havia un videoclub ple de pel·lícules i a l'entrada hi havia un rètol lluminós molt bonic que deia el lema d'aquesta casa, que és una imatge val per mil paraules. I vet aquí un dia que la clientela ja se n'havia anat, però encara no havien tancat els llums, van entrar al videoclub dues rates, l'Amàlia i l'Amèlia. I van dir: "Què fem avui?" Aleshores l'Amèlia se'n va anar de seguida cap al racó de la sèrie B i va agafar una pel·lícula poc coneguda, mentre que l'Amàlia va agafar Mort a Venècia. Llavors la va començar a rosegar i l'Amèlia li va dir: "Què, què te'n sembla?", i l'Amàlia li va contestar: "Mmm... Em va agradar més la novel·la."

  16. MEMS and mil/aero: technology push and market pull

    Clifford, Thomas H.

    2001-04-01

    MEMS offers attractive solutions to high-density fluidics, inertial, optical, switching and other demanding military/aerospace (mil/aero) challenges. However, full acceptance must confront the realities of production-scale producibility, verifiability, testability, survivability, as well as long-term reliability. Data on these `..ilities' are crucial, and are central in funding and deployment decisions. Similarly, mil/aero users must highlight specific missions, environmental exposures, and procurement issues, as well as the quirks of its designers. These issues are particularly challenging in MEMS, because of the laws of physics and business economics, as well as the risks of deploying leading-edge technology into no-fail applications. This paper highlights mil/aero requirements, and suggests reliability/qualification protocols, to guide development effort and to reassure mil/aero users that MEMS labs are mindful of the necessary realities.

  17. NATO Pallet with Javelin Missiles, MIL-STD-1660 Tests

    2004-01-01

    The U.S. Army Defense Ammunition Center (DAC), Validation Engineering Division (SJMAC-DEV) conducted tests in accordance with MIL-STD-1660, "Design Criteria for Ammunition Unit Loads" on the NATO pallet with Javelin missiles...

  18. Another Look at the Draft Mil-Std-1540E Unit Random Vibration Test Requirements

    Perl, E.; Peterson, A. J..; Davis, D.

    2012-07-01

    The draft Mil-Std-1540E has been updated to reflect lessons learned since its publication as an SMC Standard in 2008, [1], and an earlier Aerospace Corporation Technical Report released in 2006, [2]. This paper discusses the technical rationale supporting some of the unit random vibration test requirements to provide better insight into their derivation and application to programs. It is intended that these requirements be tailored for each program to reflect the customer risk profile. Several tailoring options are provided and a two phase test strategy is discussed to highlight its applicability to utilizing heritage hardware in new applications.

  19. Feldspathic Meteorites MIL 090034 and 090070: Late Additions to the Lunar Crust

    Nyquist, L. E.; Shirai, N.; Yamaguchi, A.; Shih, C.-Y.; Park, J.; Ebihara, M.

    2016-01-01

    Our studies of the Miller Range lunar meteorites MIL 090034, 090036, and 090070 show them to be a diverse suite of rocks from the lunar highlands hereafter referred to as MIL 34, MIL 36, and MIL 70, resp. MIL34 and MIL70, the focus of this work, are crystalline melt breccias. Plagioclase compositions in both peak sharply around An96-97. Mg numbers of olivine vary from 58-65 with a few higher values. MIL36 is a regolith breccia. MIL 34 and MIL 70 have some of the highest Al2O3 abundances of lunar highland meteorites, indicating that they have among the largest modal abundances of plagioclase for lunar meteorites. They have lower Sc and Cr abundances than nearly all lunar highland meteorites except Dho 081, Dho 489 and Dho 733. MIL34 and MIL70 also have similar cosmic ray exposure (CRE) ages of approximately 1-2 Ma indicating they are launch paired. (MIL36 has a larger CRE age approximately greater than 70 Ma). Park et al. found a variation in Ar-Ar ages among subsamples of MIL 34 and MIL70, but preferred ages of 3500+/-110 Ma for the "Dark" phase of MIL 34 anorthite and 3520+/-30 Ma for the "Light" phase of MIL70. Bouvier et al. reported a Pb-Pb age of 3894+/-39 Ma for a feldspathic clast of MIL 34 and a similar age for a melt lithology. Here we reexamine the Rb-Sr and Sm-Nd isotopic data, which show complexities qualitatively consistent with those of the Ar-Ar and Pb-Pb data. The Sm-Nd data in particular suggest that the feldspathic compositions of MIL 34 and MIL 70 formed during initial lunar geochemical differentiation, and REE modeling suggests a relatively late-stage formation.

  20. Curation and Allocation of the New Antarctic Nakhlite, MIL03346

    McBride, K. M.; Righter, K.; Satterwhite, C. E.; Schwarz, C.; Robinson, P.

    2005-01-01

    In January 2004, the ANSMET reconnaissance field team (Fig. 1) working in the Miller Range of the Transantarctic Mountains discovered a 715 g achondrite that was instantly recognized as unique. Named MIL03346, initial processing (NASA Johnson Space Center or JSC) and classification (Smithsonian Institution or SI) revealed this achondrite to be a nakhlite (Fig. 2). MIL03346 is the seventh nakhlite recognized in world collections [2], the third nakhlite returned from Antartica, and the first nakhlite in the US Antarctic collection (Table 1). The following is a summary of the steps taken in the processing and allocating of MIL 03346 and some comparisons to some other lunar and martian meteorites processed and allocated at JSC.

  1. The flexibility of modified-linker MIL-53 materials.

    Munn, Alexis S; Pillai, Renjith S; Biswas, Shyam; Stock, Norbert; Maurin, Guillaume; Walton, Richard I

    2016-03-14

    The flexibility of eight aluminium hydroxo terephthalates [Al(OH)(BDC-X)]·n(guest) (BDC = 1,4-benzene-dicarboxylate; X = -H, -CH3, -Cl, -Br, -NH2, -NO2, -(OH)2, -CO2H) crystallising in the MIL-53-type structure was investigated upon thermal dehydration of as-made samples, superhydration and methanol adsorption/desorption using in situ powder X-ray diffraction (PXRD). Profile fitting was used to determine lattice parameters as a function of time and/or temperature to describe their structural evolution. It has thus been shown that while methanol vapour adsorption induces an opening of all the modified frameworks, except the -NH2 material, superhydration only leads to open structures for Al-MIL-53-NO2, -Br and -(OH)2. All the MIL-53 solids, except Al-MIL-53-(OH)2 are present in the open structures upon thermal dehydration. In addition to the exploration of the breathing behavior of this MIL-53 series, the issue of disorder in the distribution of the functional groups between the organic linkers was explored. As a typical illustration, density functional theory calculations were carried out on different structures of Al-MIL-53-Cl, in which the distribution of -Cl within two adjacent BDC linkers is varied. The results show that the most energetically stable configuration leads to the best agreement with the experimental PXRD pattern. This observation supports that the distribution of the selected linker substituent in the functionalised solid is governed by energetics and that there is a preference for an ordering of this arrangement.

  2. Augmentation du rendement des producteurs de petits mils par leur ...

    29 avr. 2016 ... Image. Cultivateurs du petit mils en Inde. Une plus grande diversité de variétés de petit mil contribue à réduire la vulnérabilité à l'égard des mauvaises conditions météorologiques. En dépit du fait qu'ils ont une teneur élevée en micronutriments et en fibres alimentaires, présentent un indice glycémique ...

  3. Metal organic framework MIL-101(Cr) for dehydration reactions

    under vapour phase conditions in the temperature range of 513–533 K and time on stream (TOS) at 513 K. Cr-MIL-101 ... gies and potential applications in gas storage, sep- aration ... these materials have not been explored much. Recently .... The products were collected in ice cold trap and ... There is no change in the crys-.

  4. Compact, Low-Overhead, MIL-STD-1553B Controller

    Katz, Richard; Barto, Rod

    2009-01-01

    A compact and flexible controller has been developed to provide MIL-STD- 1553B Remote Terminal (RT) communications and supporting and related functions with minimal demand on the resources of the system in which the controller is to be installed. (MIL-STD-1553B is a military standard that encompasses a method of communication and electrical-interface requirements for digital electronic subsystems connected to a data bus. MIL-STD-1553B is commonly used in defense and space applications.) Many other MIL-STD-1553B RT controllers are complicated, and to enable them to function, it is necessary to provide software and to use such ancillary separate hardware devices as microprocessors and dual-port memories. The present controller functions without need for software and any ancillary hardware. In addition, it contains a flexible system interface and extensive support hardware while including on-chip error-checking and diagnostic support circuitry. This controller is implemented within part of a modern field-programmable gate array.

  5. Mil rosas roubadas, Work of Silviano Santiago a Bakhitinian Analysis

    Renata Coelho Marchezan

    2017-10-01

    Full Text Available This article analyzes Mil rosas roubadas, written by Silviano Santiago in 2014, dealing with the notions of (autobiography, (autobiographical novel, metafiction and autofiction. Although the creation of this last word may indicate the existence of a new genre – it is even adopted by the writer himself to name his work –, the article shows the pertinence of placing Mil rosas roubadas in the route of the transformations and stylisations of the (autobiographical novel, such as examined by M. Bakhtin. The novel is, for Bakhtin, a genre without rigid forms, an unfinished genre, as it always follows the inflections of social life. In this way the ressemantization of the self, proposed by Silviano Santiago, is analyzed.

  6. Metal organic framework MIL-101 for radioiodine capture and storage

    Assaad, Thaer; Assfour, Bassem

    2017-09-01

    we report on the use of metal organic frameworks(MOFs) for radioiodine recovery and storage. One MOF (namely MIL-101) was prepared and investigated in detail to demonstrate the iodine removal efficiency and capacity of MOFs. The typical sorption kinetics and uptake isotherms were measured using radioactive iodine (123 I) for the first time. Our measurements indicate that MOFs can capture and store radioiodine in very high efficiency and fast kinetics.

  7. MIL-HDBK-338: Environmental Conversion Table Correction

    Hark, Frank; Novack, Steven

    2017-01-01

    In reliability analysis, especially for launch vehicles, limited data is frequently a problem. Component data from other environments must be used. MIL-HBK-338 has a matrix showing the conversation between environments. Due to round off the conversions are not commutative, converting from A to B will not equal converting from B to A. Agenda: Introduction to environment conversions; Original table; Original table with edits; How big is the problem?; First attempt at correction; Proposed solution.

  8. Coordination polymer nanobamboos of {Fe(x)In(1-x)}-MIL-88B: induced formation of a virtual In-MIL-88B.

    Park, Shin Ae; Lee, Hee Jung; Cho, Yea Jin; Choi, Sora; Oh, Moonhyun

    2014-05-05

    A precise fabrication of nanobamboo structures made from hybrid coordination polymers of the type {Fex In1-x }-MIL-88B is demonstrated. The compositions of the hybrid coordination polymer nanobamboos of {Fex In1-x }-MIL-88B (x=0.06, 0.19, or 0.75) are regulated by altering the amount of metal ions used in the reactions. Interestingly, the formation of a virtual In-MIL-88B (precise structure, {Fe0.06 In0.94 }-MIL-88B), which cannot be created in a typical reaction, is induced by the assistance of a Fe-MIL-88B structure. The a and c cell parameters of {Fe0.06 In0.94 }-MIL-88B are calculated at 10.95 and 19.86 Å, respectively. These values of {Fe0.06 In0.94 }-MIL-88B are larger than those of pure Fe-MIL-88B owing to the large ionic size of In(3+) within the framework. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Multifunctional polyoxometalates encapsulated in MIL-100(Fe): highly efficient photocatalysts for selective transformation under visible light.

    Liang, Ruowen; Chen, Rui; Jing, Fenfen; Qin, Na; Wu, Ling

    2015-11-07

    H3PMo12O40 molecules have been successfully encapsulated in the cavities of MIL-100(Fe) via a facile hydrothermal method (denoted as HPMo@MIL-100(Fe)). A series of characterization has corroborated the insertion of H3PMo12O40 within the cavities of MIL-100(Fe). The resulting HPMo@MIL-100(Fe) nanocomposites have exhibited much higher photoactivity than the original-MIL-100(Fe) toward the photocatalytic selective oxidation of benzylic alcohols and the reduction of Cr(vi) under visible light irradiation (λ≥ 420 nm). The higher photoactivity of HPMo@MIL-100(Fe) can be attributed to the integrative effect of enhanced light absorption intensity and more efficient separation of photogenerated electron-hole pairs. The host porous structure of MIL-100(Fe) can achieve a uniform composition with H3PMo12O40, which is significantly important for producing highly reactive dispersed H3PMo12O40 molecules and enhancing the photocatalytic activity of HPMo@MIL-100(Fe) nanocomposites. And the immobilized H3PMo12O40 molecules are more convenient for recycling. Importantly, almost no Fe and Mo ions leach from the MIL-100(Fe) during the reaction, which verifies the photostability of the HPMo@MIL-100(Fe). In addition, possible photocatalytic redox reaction mechanisms have been investigated.

  10. Iron metal-organic frameworks MIL-88B and NH2-MIL-88B for the loading and delivery of the gasotransmitter carbon monoxide.

    Ma, Mingyan; Noei, Heshmat; Mienert, Bernd; Niesel, Johanna; Bill, Eckhard; Muhler, Martin; Fischer, Roland A; Wang, Yuemin; Schatzschneider, Ulrich; Metzler-Nolte, Nils

    2013-05-17

    Crystals of MIL-88B-Fe and NH2-MIL-88B-Fe were prepared by a new rapid microwave-assisted solvothermal method. High-purity, spindle-shaped crystals of MIL-88B-Fe with a length of about 2 μm and a diameter of 1 μm and needle-shaped crystals of NH2-MIL-88B-Fe with a length of about 1.5 μm and a diameter of 300 nm were produced with uniform size and excellent crystallinity. The possibility to reduce the as-prepared frameworks and the chemical capture of carbon monoxide in these materials was studied by in situ ultrahigh vacuum Fourier-transform infrared (UHV-FTIR) spectroscopy and Mössbauer spectroscopy. CO binding occurs to unsaturated coordination sites (CUS). The release of CO from the as-prepared materials was studied by a myoglobin assay in physiological buffer. The release of CO from crystals of MIL-88B-Fe with t(1/2) = 38 min and from crystals of NH2-MIL-88B-Fe with t(1/2) = 76 min were found to be controlled by the degradation of the MIL materials under physiological conditions. These MIL-88B-Fe and NH2-MIL-88B-Fe materials show good biocompatibility and have the potential to be used in pharmacological and therapeutic applications as carriers and delivery vehicles for the gasotransmitter carbon monoxide. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Barrio residencial de Gratosoglio, Milán

    Giannini, Sandro

    1967-04-01

    Full Text Available The group of 23 buildings in the residential zone of Gratosoglio, which provide space for 1,000 dwellings, has been built by the firm «Fintech Italcamus». This Italian firms applies in Italy the «Raymond Camus» system, which is a positive aid to heavy prefabrication in housing projects. The above group of buildings constitute part of the General Building Scheme so successfully initiated by the Autonomous Building Institute of the Province of Milan, with the purpose of helping to overcome the extensive lack of housing in the Milan region.El grupo de edificios levantado en el Barrio Residencial de Gratosoglio, Milán (23, con un total de 1.000 viviendas, ha sido construido por la firma «Fintech Italcamus», Sociedad italiana que aplica en Italia el sistema «Raymond Camus» y constituye una aportación positiva de la prefabricación pesada a la edificación residencial. Este conjunto forma parte del Plan General de edificación, emprendido con tanto éxito como acierto por el Instituto Autónomo de la Vivienda de la Provincia de Milán, para solucionar los problemas que la gigantesca presión demográfica planteaba en dicha provincia.

  12. Geochemistry of Lunar Highland Meteorites Mil, 090034, 090036 AND 090070

    Shirai, N.aoki; Ebihara, M.; Sekimoto, S.; Yamaguchi, A.; Nyquist, L.; Shih, C.-Y.; Park, J.; Nagao, K.

    2012-01-01

    Apollo and Luna samples were collected from a restricted area on the near side of the Moon, while the source craters of the lunar meteorites are randomly distributed. For example, Takeda et al. [1] and Yamaguchi et al. [2] found a variety of lithic clasts in Dho 489 and Y 86032 which were not represented by Apollo samples, and some of these clasts have lower rare earth elements (REE) and FeO abundances than Apollo anorthosites, respectively. Takeda et al. [1] and Yamaguchi et al. [2] concluded that Dho 489 and Y 86032 originated from the lunar farside. Therefore, lunar meteorites provide an opportunity to study lunar surface rocks from areas not sampled by Apollo and Luna missions. Three lunar anorthitic breccias (MIL 090034, 090036 and 090070) were found on the Miller Range Ice Field in Antarctica during the 2009-2010 ANSMET season [3]. In this study, we determined elemental abudnances for MIL 090034, 090036 and 090070 by using INAA and aimed to characterize these meteorites in chemical compositions in comparison with those for other lunar meteorites and Apollo samples.

  13. Synergy of mIL-21 and mIL-15 in enhancing DNA vaccine efficacy against acute and chronic Toxoplasma gondii infection in mice.

    Li, Zhong-Yuan; Chen, Jia; Petersen, Eskild; Zhou, Dong-Hui; Huang, Si-Yang; Song, Hui-Qun; Zhu, Xing-Quan

    2014-05-23

    The synergistic protective efficacy of murine interleukin 21 (mIL-21) and mIL-15 administrated with DNA vaccine against acute and chronic Toxoplasma gondii infection in mice was investigated using T. gondii MIC8 (TgMIC8) as a model. We cloned mIL-21 and mIL-15 from splenic tissues of Kunming mice, and constructed eukaryotic plasmid pVAX/mIL-15, pVAX/mIL-21, and pVAX/mIL-21/mIL-15, respectively. After immunizing with pVAX/TgMIC8 in the presence or absence of these cytokines, immune responses were analyzed using lymphoproliferative assay, cytokine and serum antibody measurements, flow cytometric surface markers on lymphocytes and protection against acute and chronic T. gondii infection. Mice receiving pVAX/TgMIC8 alone developed a strong humoral responses and Th1 type cellular immune responses, and showed an increase of CD4+ and CD8+ T cells compared with all the controls. Adding pVAX/mIL-21 to pVAX/TgMIC8 compared to pVAX/TgMIC8 resulted in only a slight increase in humoral and cellular immune responses, and this immune response was lower than that induced by the pVAX/mIL-15 combined with pVAX/TgMIC8. Co-administration of pVAX/mIL-21/mIL-15 combined with pVAX/TgMIC8 elicited the strongest humoral and cellular immune responses among all the groups, leading to significantly increased survival time against acute infection and the significant reduction of tissue cysts, compared to all the controls. Synergy of mIL-21 and mIL-15 can facilitate specific humoral as well as cellular immune responses elicited by DNA vaccine against acute and chronic T. gondii infection in mice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Experimentally determined coordinates for three MILS hydrophones near Ascension Island

    Harben, P.E.; Hollfelder, J.R.; Rodgers, A.J.

    1999-01-01

    We conducted an airgun survey in the waters of Ascension Island in May 1999 to determine new locations and depths for three Missile Impact Location System (MILS) hydrophones (ASC23, ASC24, and ASC26) currently in use by the Prototype International Data Center (PIDC) and the National Data Center (NDC). The nominal and new locations are summarized. Although not rigorous, errors in the new locations and depths are conservatively estimated to be less than 100 m. The hydrophones are either on or near the ocean bottom in all three cases. The new depths are consistent with the following: Direct-phase airgun arrivals; Bathymetry determined along the track of the ship used for this airgun survey; Reflected phases from the airgun data; Depths given in the original hydrophone installation report. (author)

  15. MIL-HDBK-338-Environmental Conversion Table Correction

    Hark, Frank; Novack, Steve

    2017-01-01

    In reliability analysis for space launch vehicles, limited data is frequently a challenge due to the pure number of launches. A common solution is to use surrogate historical data of similar components from other industries (military data). The operating environment of the common data may be different from that of the necessary target analysis. The military electronic design handbook (MIL-HDBK-338) has a table for converting Mean Time Between Failure (MTBF) data from one environment to another. However, the table has some discrepancies and rounding of complementary conversions; namely going from environment A to B does not given the same result as going from B to A. This presentation will show the discrepancies in the original conversation table, the greater than expected magnitude, the problem with the updated published table and a suggested corrected table to reference when doing MTBF data environment conversion.

  16. Nanometric MIL-125-NH2 metal–organic framework as a potential nerve agent antidote carrier

    Vilela, S.M.F.; Salcedo-Abraira, P; Colinet, I.; Salles, F.; Koning, M.C. de; Joosen, M.J.A.; Serre, C.; Horcajada, P.

    2017-01-01

    The three-dimensional (3D) microporous titanium aminoterephthalate MIL-125-NH_2 (MIL: Material of Institut Lavoisier) was successfully isolated as monodispersed nanoparticles, which are compatible with intravenous administration, by using a simple, safe and low-cost synthetic approach (100 °C/32 h

  17. MIL-68 (In) nano-rods for the removal of Congo red dye from aqueous solution.

    Jin, Li-Na; Qian, Xin-Ye; Wang, Jian-Guo; Aslan, Hüsnü; Dong, Mingdong

    2015-09-01

    MIL-68 (In) nano-rods were prepared by a facile solvothermal synthesis using NaOAc as modulator agent at 100°C for 30 min. The BET test showed that the specific surface area and pore volume of MIL-68 (In) nanorods were 1252 m(2) g(-1) and 0.80 cm(3) g(-1), respectively. The as-prepared MIL-68 (In) nanorods showed excellent adsorption capacity and rapid adsorption rate for removal of Congo red (CR) dye from water. The maximum adsorption capacity of MIL-68 (In) nanorods toward CR reached 1204 mg g(-1), much higher than MIL-68 (In) microrods and most of the previously reported adsorbents. The adsorption process of CR by MIL-68 (In) nano-rods was investigated and found to be obeying the Langmuir adsorption model in addition to pseudo-second-order rate equation. Moreover, the MIL-68 (In) nanorods showed an acceptable reusability after regeneration with ethanol. All information gives an indication that the as-prepared MIL-68 (In) nanorods show their potential as the adsorbent for highly efficient removal of CR in wastewater. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Modulated synthesis of chromium-based metal-organic framework (MIL-101) with enhanced hydrogen uptake

    Ren, Jianwei

    2014-08-01

    Full Text Available Modulated synthesis of MIL-101(Cr) in high yield and with good reproducibility using formic acid as a modulator is reported. Higher molar ratio of formic acid/CrCl(sub3) was found to form better shape-defined MIL-101(Cr) crystals with higher surface...

  19. Hydrogen storage behaviors of Ni-doped graphene Oxide/MIL-101 hybrid composites.

    Lee, Seul-Yi; Park, Soo-Jin

    2013-01-01

    In this work, Ni-doped graphene oxide/MIL-101 hybrid composites (Ni--GO/MIL) were prepared to investigate their hydrogen storage behaviors. Ni--GO/MIL was synthesized by adding Ni--GO in situ during the synthesis of MIL-101 using a hydrothermal process, which was conducted by conventional convection heating with Cr(III) ion as a metal center and telephthalic acid as organic ligands. The crystalline structures and morphologies were measured by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The specific surface area and micropore volume were investigated by N2/77 K adsorption isotherms using the Brunauer-Emmett-Teller (BET) method and Dubinin-Radushkevic (D-R) equation, respectively. The hydrogen storage capacity was investigated by BEL-HP at 77 K and 1 bar. The obtained results show that Ni--GO/MIL presents new directions for achieving novel hybrid materials with higher hydrogen storage capacity.

  20. Master in ICT and Learning

    Danielsen, Oluf

    2004-01-01

    The Master in ICT and Learning (MIL)was started in 2000, and it is owned in collaboration by five Danish universities. It is an accredited virtual part-time 2-year education. MIL is unique in that it builds on the pedagogical framework of project pedagogy and is based in virtual collaboration....... It is organized around ICT and Learning. This is illustrated through a presentation of the study program, the four modules, the projects and the master thesis....

  1. CO2/CH4 Separation by a Mixed Matrix Membrane of Polymethylpentyne/MIL-53 Particles

    Reza Abedini

    2014-10-01

    Full Text Available The effect of Materials Institute Lavoisier-53 (MIL-53 particles on gas transport properties of polymethylpentyne (PMP was investigated. MIL-53 was added to the polymer matrix with different loadings of 10, 20 and 30 wt%. The properties of MIL-53 and prepared membranes were analyzed through FTIR, SEM and TGA methods. The adsorption of CO2 and CH4 was conducted and analyzed accurately through Langmuir equation to investigate the gas transport properties of membranes. The results from TGA showed that degradation temperature (Td increases significantly with increasing MIL-53 loading. SEM images demonstrated that MIL-53 particles dispersed well in polymer matrix with no considerable agglomeration and no non-selective void formation at polymer/filler interface. In addition, CO2 and CH4 permeability measurement along with calculation of CO2/CH4 selectivity were performed. The results showed that the permeability of gases (especially for CO2 increased significantly by increasing the MIL-53 loading. Additionally, CO2/CH4 selectivity showed an increasing trend with increasing the MIL-53 weight percent. Unlike CH4, the CO2 solubility coefficient increased with increasing the MIL-53 loading because of high free volume of membrane and selective adsorption of CO2 with MIL-53. Despite CO2 solubility enhancement its diffusivity coefficient remained more or less unchanged. The enhancement in CH4 permeability has been mainly attributed to its slight incremental diffusivity due to the membrane's increasingly higher free volume. Finally, a comparison between membranes performance and CO2/CH4 Robeson upper bound showed that, the performance of membranes improved due to the presence of MIL-53 which was very close to the Robeson bound.

  2. Design of a Networked Learning Master Environment for Professionals

    Dirckinck-Holmfeld, Lone

    2010-01-01

    The paper is presenting the overall learning design of MIL (Master in ICT and Learning). The learning design is integrating a number of principles: 1. Principles of problem and project based learning 2. Networked learning / learning in communities of practice. The paper will discuss how these pri......The paper is presenting the overall learning design of MIL (Master in ICT and Learning). The learning design is integrating a number of principles: 1. Principles of problem and project based learning 2. Networked learning / learning in communities of practice. The paper will discuss how...

  3. Adsorptive removal of dibenzothiophene from model fuels over one-pot synthesized PTA@MIL-101(Cr) hybrid material

    Jia, Shao-Yi; Zhang, Yan-Fei [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China); Liu, Yong [School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin (China); Qin, Feng-Xiang; Ren, Hai-Tao [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China); Wu, Song-Hai, E-mail: songhaiwu@gmail.com [School of Chemical Engineering and Technology, Tianjin University, Tianjin (China)

    2013-11-15

    Highlights: • One-pot synthesized PTA@MIL-101(Cr) shows high capacity of benzothiophene. • PTA/MIL-101(Cr) obtained via post-modification performs poor in the adsorption. • PTA and MIL-101(Cr) exhibit synergetic effect on adsorption of benzothiophene. • In the presence of aromatics, PTA@MIL-101(Cr) and MIL-101(Cr) remain their capacity. • PTA-dispersed MOFs adsorb dibenzothiophene through acid–base interaction. -- Abstract: Hybrid nanomaterials comprising phosphotungstic acid (PTA) and MIL-101(Cr) were prepared through one-pot synthesis and post-modification methods and then were used as adsorbents of dibenzothiophene (DBT) from simulated diesel fuels. Samples obtained by different ways (encapsulation and impregnation) were characterized by nitrogen adsorption, transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectrum (FT-IR) and series of adsorption experiments. The equilibrium adsorption capacities of PTA@MIL-101(Cr) illustrated that the direct introduction of PTA into MIL-101(Cr) during synthesis resulted in a 10.7% increase compared with MIL-101(Cr). However, porous hybrid adsorbent PTA/MIL-101(Cr) prepared via post-modification method exhibited lower adsorption capacity than virgin MIL-101(Cr). The theoretical maximum adsorption capacity (Q{sub 0}) of PTA@MIL-101(Cr) is 136.5 mg S/g adsorbent, 4.2 times of MIL-101(Cr). Even in competitive adsorption between aromatic compounds, which possess strong affinity with MOFs, and DBT, PTA@MIL-101(Cr) and MIL-101(Cr) remained their effectiveness in removal of DBT in the system. Based on these results, it can be presumed that MIL-101(Cr), modified properly, can be used as a promising adsorbent for eliminating aromatics and S-compounds in commercial fuels simultaneously.

  4. Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

    Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

    2013-12-26

    A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) → Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) → V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) → Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine.

  5. The Oxygen Isotopic Composition of MIL 090001: A CR2 Chondrite with Abundant Refractory Inclusions

    Keller, Lindsay P.; McKeegan, K. D.; Sharp, Z. D.

    2012-01-01

    MIL 090001 is a large (>6 kg) carbonaceous chondrite that was classified as a member of the CV reduced subgroup (CVred) that was recovered during the 2009-2010 ANSMET field season [1]. Based on the abundance of refractory inclusions and the extent of aqueous alteration, Keller [2] suggested a CV2 classification. Here we report additional mineralogical and petrographic data for MIL 090001, its whole-rock oxygen isotopic composition and ion microprobe analyses of individual phases. The whole rock oxygen isotopic analyses show that MIL 090001 should be classified as a CR chondrite.

  6. Molecular simulations of a CO2/CO mixture in MIL-127

    Chokbunpiam, Tatiya; Fritzsche, Siegfried; Parasuk, Vudhichai; Caro, Jürgen; Assabumrungrat, Suttichai

    2018-03-01

    Adsorption and diffusion of an equimolar feed mixture of CO2 and CO in MIL-127 at three different temperatures and pressures up to 12 bar were investigated by molecular simulations. The adsorption was simulated using Gibbs-Ensemble Monte Carlo (GEMC). The structure of the adsorbed phase and the diffusion in the MIL were investigated using Molecular Dynamics (MD) simulations. The adsorption selectivity of MIL-127 for CO2 over CO at 233 K was about 15. When combining adsorption and diffusion selectivities, a membrane selectivity of about 12 is predicted. For higher temperatures, both adsorption and diffusion selectivity are found to be smaller.

  7. Ciberprens@. El medio de los ‘diez mil nombres’

    Dr. José Álvarez Marcos

    2000-01-01

    Full Text Available Los chinos han traducido el significado de World Wide Web como "la red de diez mil dimensiones en el cielo y la tierra". La telaraña cibernética no sólo se ha convertido en un gigantesco hipermercado de la información, donde confluyen medios tradicionales e innovadoras propuestas comunicativas, sino que aparece como el fenómeno de mayor impacto social de los últimos años. En un mundo donde la evolución tecnológica acorta cada vez más los ciclos de la innovación, como bien señala Díaz Nosty, Internet tiene visos de consolidarse como el embrión de la primera gran solución sostenible desde que apareció la televisión, al menos en una interpretación hecha desde el campo de análisis de los medios

  8. Adsorptive removal of dibenzothiophene from model fuels over one-pot synthesized PTA@MIL-101(Cr) hybrid material.

    Jia, Shao-Yi; Zhang, Yan-Fei; Liu, Yong; Qin, Feng-Xiang; Ren, Hai-Tao; Wu, Song-Hai

    2013-11-15

    Hybrid nanomaterials comprising phosphotungstic acid (PTA) and MIL-101(Cr) were prepared through one-pot synthesis and post-modification methods and then were used as adsorbents of dibenzothiophene (DBT) from simulated diesel fuels. Samples obtained by different ways (encapsulation and impregnation) were characterized by nitrogen adsorption, transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectrum (FT-IR) and series of adsorption experiments. The equilibrium adsorption capacities of PTA@MIL-101(Cr) illustrated that the direct introduction of PTA into MIL-101(Cr) during synthesis resulted in a 10.7% increase compared with MIL-101(Cr). However, porous hybrid adsorbent PTA/MIL-101(Cr) prepared via post-modification method exhibited lower adsorption capacity than virgin MIL-101(Cr). The theoretical maximum adsorption capacity (Q0) of PTA@MIL-101(Cr) is 136.5mg S/g adsorbent, 4.2 times of MIL-101(Cr). Even in competitive adsorption between aromatic compounds, which possess strong affinity with MOFs, and DBT, PTA@MIL-101(Cr) and MIL-101(Cr) remained their effectiveness in removal of DBT in the system. Based on these results, it can be presumed that MIL-101(Cr), modified properly, can be used as a promising adsorbent for eliminating aromatics and S-compounds in commercial fuels simultaneously. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Hydrothermal crystal growth and Vernier structures of the metal benzenedicarboxylates MIL-47 and MIL-53 containing guest molecules of benzenecarboxylic acid

    Wang, Xiqu; Jacobson, Allan J., E-mail: ajjacob@uh.edu

    2016-04-15

    The nanoporous frameworks VO(bdc), MIL-47, and M(OH)(bdc), MIL-53; bdc=1,4-benzenedicarboxylate, can absorb various guest species in their channels. As synthesized, the channels are filled with H{sub 2}bdc molecules that have been reported to be disordered, except for [In(OH)bdc](H{sub 2}bdc){sub 3/4}, 1, which has a inorganic-organic hybrid Vernier structure with the H{sub 2}bdc molecules forming an ordered sublattice. Based on X-ray data from large single crystals grown by hydrothermal techniques, similar Vernier structures have been found for MIL-47, [VO(bdc)](H{sub 2}bdc){sub 5/7}, 2, MIL-53Al, [Al(OH)(bdc)](H{sub 2}bdc){sub 11/16}, 3, and MIL-53Ga, [Ga(OH)(bdc)](H{sub 2}bdc){sub 12/17}, 4. The Vernier structures of 2–4 at room temperature were determined based on superstructure unit cells that index both host and guest sublattices: 2, space group P2{sub 1}, a=23.903(2), b=17.191(2), c=25.722(2) Å, β=105.914(8)°; 3, P2{sub 1}/n, a=105.224(4), b=12.2441(5), c=17.0143(6) Å, β=89.99(1)°; 4, P2{sub 1}, a=114.562(5), b=12.1503(5), c=17.4275(7) Å, β=89.99(1)°. The number of guest H{sub 2}bdc molecules per framework metal ion is determined by the ratio of the repeat distances of the two sublattices which depends on the size of the metal ion in the octahedral chain. The octahedral chains are parallel to [201] in 2, and to [100] in 3 and 4. Remarkably, all atoms in 3 and 4 show significant sinusoidal modulations transverse to the chain axis. - Graphical abstract: The sinusoidal modulation along the channel axis direction involving all atoms in the structure of [Al(OH)(bdc)](H{sub 2}bdc){sub 11/16}. - Highlights: • Crystal growth of MIL-47, MIL-53Al, and MIL-53Ga. • The Vernier structures have corner-sharing MO6 octrahedral chains and chains of H2BDC molecules. • The stoichiometry is determined by the ratio of the host framework to the guest H2BDC column lengths. • A correlation is established between the stoichiometry and the radius of the metal ion

  10. Hydrothermal crystal growth and Vernier structures of the metal benzenedicarboxylates MIL-47 and MIL-53 containing guest molecules of benzenecarboxylic acid

    Wang, Xiqu; Jacobson, Allan J.

    2016-01-01

    The nanoporous frameworks VO(bdc), MIL-47, and M(OH)(bdc), MIL-53; bdc=1,4-benzenedicarboxylate, can absorb various guest species in their channels. As synthesized, the channels are filled with H 2 bdc molecules that have been reported to be disordered, except for [In(OH)bdc](H 2 bdc) 3/4 , 1, which has a inorganic-organic hybrid Vernier structure with the H 2 bdc molecules forming an ordered sublattice. Based on X-ray data from large single crystals grown by hydrothermal techniques, similar Vernier structures have been found for MIL-47, [VO(bdc)](H 2 bdc) 5/7 , 2, MIL-53Al, [Al(OH)(bdc)](H 2 bdc) 11/16 , 3, and MIL-53Ga, [Ga(OH)(bdc)](H 2 bdc) 12/17 , 4. The Vernier structures of 2–4 at room temperature were determined based on superstructure unit cells that index both host and guest sublattices: 2, space group P2 1 , a=23.903(2), b=17.191(2), c=25.722(2) Å, β=105.914(8)°; 3, P2 1 /n, a=105.224(4), b=12.2441(5), c=17.0143(6) Å, β=89.99(1)°; 4, P2 1 , a=114.562(5), b=12.1503(5), c=17.4275(7) Å, β=89.99(1)°. The number of guest H 2 bdc molecules per framework metal ion is determined by the ratio of the repeat distances of the two sublattices which depends on the size of the metal ion in the octahedral chain. The octahedral chains are parallel to [201] in 2, and to [100] in 3 and 4. Remarkably, all atoms in 3 and 4 show significant sinusoidal modulations transverse to the chain axis. - Graphical abstract: The sinusoidal modulation along the channel axis direction involving all atoms in the structure of [Al(OH)(bdc)](H 2 bdc) 11/16 . - Highlights: • Crystal growth of MIL-47, MIL-53Al, and MIL-53Ga. • The Vernier structures have corner-sharing MO6 octrahedral chains and chains of H2BDC molecules. • The stoichiometry is determined by the ratio of the host framework to the guest H2BDC column lengths. • A correlation is established between the stoichiometry and the radius of the metal ion. • All atoms in the Al and Ga compounds show sinusoidal

  11. Synthesis of MIL-100(Fe at Low Temperature and Atmospheric Pressure

    Jing Shi

    2013-01-01

    Full Text Available MIL-100(Fe, a mesoporous metal-organic framework (MOF, has a large BET specific surface area and pore volume with the presence of a significant amount of accessible Lewis acid metal sites upon dehydration. The structural characteristics of MIL-100(Fe make it a good candidate for potential applications in gas storage, separation, and heterogeneous catalysis. Mainly, this MOF is obtained by the hydrothermal synthesis in a Teflon-lined autoclave at high temperature (>150°C under static conditions. However, this method has several disadvantages such as high temperature, high (autogenous pressure, long time, and comparable low MOF yield. Therefore, development of a facile method for synthesis of MIL-100(Fe is vitally important for fundamental understanding and practical application. Herein, MIL-100(Fe is synthesized by a facile low-temperature (90% still could be achieved, suggesting that this simple and energy saving method has the potential to be used practically.

  12. Endurance Pump Tests With Fresh and Purified MIL-PRF-83282 Hydraulic Fluid

    Sharma, Shashi

    1999-01-01

    .... Two endurance pump tests were conducted with F-16 aircraft hydraulic pumps, using both fresh and purified MIL-PRF-83282 hydraulic fluid, to determine if fluid purification had any adverse effect on pump life...

  13. Synthesis of a hybrid MIL-101(Cr)/ZTC composite for hydrogen storage applications

    Musyoka, Nicholas M

    2016-06-01

    Full Text Available Metal–organic frameworks (MOFs) hybrid composites have recently attracted considerable attention in hydrogen storage applications. In this study a hybrid composite of zeolite templated carbon (ZTC) and Cr-based MOF (MIL-101) was synthesised...

  14. Small Explorer Data System MIL-STD-1773 fiber optic bus

    Flanegan, Mark; Label, Ken

    1992-01-01

    The MIL-STD-1773 Fiber Optic Data Bus as implemented in the GSFC Small Explorer Data System (SEDS) for the Small Explorer Program is described. It provides an overview of the SEDS MIL-STD-1773 bus components system design considerations, reliability figures, acceptance and qualification testing requirements, radiation requirements and tests, error handling considerations, and component heritage. The first mission using the bus will be launched in June of 1992.

  15. Bivalent metal-based MIL-53 analogues: Synthesis, properties and application

    Liu, Yongxin; Liu, Dan; Wang, Cheng

    2015-01-01

    Trivalent metal-based MIL-53 (Al 3+ , Cr 3+ , Fe 3+ , In 3+ ) compounds are interesting metal–organic frameworks (MOFs) with breathing effect and are promising gas sorption materials. Replacing bridging μ 2 -OH group by neutral ligands such as pyridine N-oxide and its derivatives (PNOs), the trivalent metal-based MIL-53 analogous structures could be extended to bivalent metal systems. The introduction of PNOs and bivalent metal elements endows the frameworks with new structural features and physical and chemical properties. This minireview summarizes the recent development of bivalent metal-based MIL-53 analogues (Mn 2+ , Co 2+ , Ni 2+ ), typically, focusing on the synthetic strategies and potential applications based on our own works and literatures. We present the synthetic strategy to achieve structures evolution from single-ligand-walled to double-ligand-walled channel. Properties and application of these new materials in a wide range of potential areas are discussed including thermal stability, gas adsorption, magnetism and liquid-phase separation. Promising directions of this research field are also highlighted. - Graphical abstract: The recent development of bivalent metal-based MIL-53 analogues (Mn 2+ , Co 2+ , Ni 2+ ) on their synthetic strategies, properties and potential applications was reviewed. - Highlights: • Structure features of bivalent metal-based MIL-53 analogues are illustrated. • Important properties and application are presented. • Host–guest interactions are main impetus for liquid-phase separation. • Promising directions of bivalent metal-based MIL-53 analogues are highlighted

  16. Study on adsorption refrigeration performance of MIL-101-isobutane working pair

    Ma, Liejun; Yang, Huan; Wu, Qi; Yin, Yu; Liu, Zongjian; Cui, Qun; Wang, Haiyan

    2015-01-01

    Rising concerns about pro-environment and energy conservation bring about the escalating interests in adsorption cooling systems using renewable energy. Adsorption chillers with common refrigerants (water, ethanol, methanol, etc.) face the problem that advanced technologies and intricate design considerations are required to maintain high vacuum. This paper aims at the parameters optimization of adsorption system being operated with the novel working pair, MIL-101-isobutane, under typical conditions of ice making and air-condition. Adsorption isotherms and dynamic of isobutane on MIL-101 are discussed simultaneously. When the hot water inlet temperature, cooling water temperature and desorption time are 95 °C, 30 °C and 30 min, respectively, the cooling capacity is 45.7 kJ/kg, which is 1.7 times as much as that of activated carbon–isobutane pair. Structural stability of MIL-101 subjected to 500 times adsorption/desorption cycles has been successfully verified by XRD (X-ray diffraction). - Highlights: • Adsorption isotherms and kinetic of isobutane on MIL-101 were studied. • A single bed adsorption chiller with MIL-101-isobutane pair was built. • System performed better than that using activated carbon–isobutane pair. • Stability of MIL-101 subjected to 500 ad/desorption cycles has been verified.

  17. Organic Linker Defines the Excited-State Decay of Photocatalytic MIL-125(Ti)-Type Materials.

    Santaclara, Jara G; Nasalevich, Maxim A; Castellanos, Sonia; Evers, Wiel H; Spoor, Frank C M; Rock, Kamila; Siebbeles, Laurens D A; Kapteijn, Freek; Grozema, Ferdinand; Houtepen, Arjan; Gascon, Jorge; Hunger, Johannes; van der Veen, Monique A

    2016-02-19

    Recently, MIL-125(Ti) and NH2 -MIL-125(Ti), two titanium-based metal-organic frameworks, have attracted significant research attention in the field of photocatalysis for solar fuel generation. This work reveals that the differences between these structures are not only based on their light absorption range but also on the decay profile and topography of their excited states. In contrast to MIL-125(Ti), NH2 -MIL-125(Ti) shows markedly longer lifetimes of the charge-separated state, which improves photoconversion by the suppression of competing decay mechanisms. We used spectroelectrochemistry and ultrafast spectroscopy to demonstrate that upon photoexcitation in NH2 -MIL-125(Ti) the electron is located in the Ti-oxo clusters and the hole resides on the aminoterephthalate unit, specifically on the amino group. The results highlight the role of the amino group in NH2 -MIL-125(Ti), the electron donation of which extends the lifetime of the photoexcited state substantially. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Application of Metal-Organic Framework Nano-MIL-100(Fe) for Sustainable Release of Doxycycline and Tetracycline.

    Taherzade, Seyed Dariush; Soleimannejad, Janet; Tarlani, Aliakbar

    2017-08-06

    Nanostructures of MIL-100 were synthesized and used as a drug delivery platform for two members of the Tetracycline family. Doxycycline monohydrate (DOX) and Tetracycline hydrochloride (TC) were loaded separately on nano-MIL-100 (nanoparticles of drug@carrier were abbreviated as DOX@MIL-100 and TC@MIL-100). Characterizations were carried out using FT-IR, XRD, BET, DLS, and SEM. The FT-IR spectra revealed that the drugs were loaded into the framework of the carrier. The XRD patterns of DOX@MIL-100 and TC@MIL-100 indicated that no free DOX or TC were present. It could be concluded that the drugs are well dispersed into the pores of nano-MIL-100. The microporosity of the carrier was confirmed by BJH data. BET analysis showed a reduction in the free surface for both DOX@MIL-100 and TC@MIL-100. The release of TC and DOX was investigated, and it was revealed that MIL-100 mediated the drug solubility in water, which in turn resulted in a decrease in the release rate of TC (accelerating in DOX case) without lowering the total amount of released drug. After 48 h, 96 percent of the TC was sustain released, which is an unprecedented amount in comparison with other methods.

  19. Project Learning and Virtual Collaboration

    Fibiger, Bo; Nielsen, Janni; Sorensen, Elsebeth

    2005-01-01

    to the modularity and flexibility that characterize the study and allow admission of part-time students, full-time students and students who only sign up for one accredited module. The methodology will be illustrated through empirical snapshots from selected modules in the start-up phase, and the focus...... will be directed towards problems experienced by the students. From an analytical perspective, the paper will identify and discuss fundamental problems related to the organization, flexibility, and implementation of project pedagogy online. MIL is organized around ICT and Learning and the study theme focuses...... on ICT and Learning. In addition, MIL provides a learning space where practice is under constant negotiation and reconstruction as an inherent, integrated part of the learning process. Consequently, we argue that MIL may be seen as an example of best practice in blended learning....

  20. Fracture toughness of Ceramic-Fiber-Reinforced Metallic-Intermetallic-Laminate (CFR-MIL) composites

    Vecchio, Kenneth S.; Jiang, Fengchun

    2016-01-01

    Novel Ceramic-Fiber-Reinforced-Metal-Intermetallic-Laminate (CFR-MIL) composites, Ti–Al 3 Ti–Al 2 O 3 –Al, were synthesized by reactive foil sintering in air. Microstructure controlled material architectures were achieved with continuous Al 2 O 3 fibers oriented in 0° and 90° layers to form fully dense composites in which the volume fractions of all four component phases can be tailored. Bend fracture specimens were cut from the laminate plates in divider orientation, and bend tests were performed to study the fracture behavior of CFR-MIL composites under three-point and four-point bending loading conditions. The microstructures and fractured surfaces of the CFR-MIL composites were examined using optical microscopy and scanning electron microscopy to establish a correlation between the fracture toughness, fracture surface morphology and microstructures of CFR-MIL composites. The fracture and toughening mechanisms of the CFR-MIL composites are also addressed. The present experimental results indicate that the fracture toughness of CFR-MIL composites determined by three- and four-point bend loading configurations are quite similar, and increased significantly compared to MIL composites without ceramic fiber reinforcement. The interface cracking behavior is related to the volume fraction of the brittle Al 3 Ti phase and residual ductile Al, but the fracture toughness values appear to be insensitive to the ratio of these two phases. The toughness appears to be dominated by the ductility/strength of the Ti layers and the strength and crack bridging effect of the ceramic fibers.

  1. MIL-53(Fe) MOF-mediated catalytic chemiluminescence for sensitive detection of glucose.

    Yi, Xueling; Dong, Wenfei; Zhang, Xiaodan; Xie, Jianxin; Huang, Yuming

    2016-12-01

    Various analytical applications of metal-organic frameworks (MOFs) have been rapidly developed in the past few years. However, the employment of MOFs as catalysts in chemiluminescence (CL) analysis is rare. Here, for the first time, we found that MIL-53(Fe) MOFs could significantly enhance the CL of luminol in the presence of H 2 O 2 in an alkaline medium. The CL intensity in the luminol-H 2 O 2 -MIL-53(Fe) system was about 20 times higher than that in the luminol-H 2 O 2 system. Moreover, the XRD pattern of MIL-53(Fe) after CL reaction was almost the same as that of the original MIL-53(Fe), confirming the catalytic role of MIL-53(Fe) in the luminol-H 2 O 2 -MIL-53(Fe) system. The possible mechanism behind the enhancing phenomenon was discussed based on the results from the CL spectra, FL probe experiments, and active oxygen species measurements. By coupling with the glucose oxidase-based catalytic oxidation reaction, a sensitive and selective CL method was developed for the detection of glucose. There is a linear relationship between the logarithm of CL intensity and the logarithm of glucose concentration in the range from 0.1 to 10 μM, and a detection limit of 0.05 μM (S/N = 3) is obtained. The proposed method has been applied to the determination of glucose in human serum samples with satisfactory results. Graphical abstract MIL-53(Fe) MOFs are found to greatly enhance the chemiluminescence emission of the luminol-H 2 O 2 system, and this finding resulted in a new chemiluminescence method for biosensing of glucose when coupled with the glucose oxidase.

  2. Nanometric MIL-125-NH2 Metal–Organic Framework as a Potential Nerve Agent Antidote Carrier

    Sérgio M. F. Vilela

    2017-10-01

    Full Text Available The three-dimensional (3D microporous titanium aminoterephthalate MIL-125-NH2 (MIL: Material of Institut Lavoisier was successfully isolated as monodispersed nanoparticles, which are compatible with intravenous administration, by using a simple, safe and low-cost synthetic approach (100 °C/32 h under atmospheric pressure so that for the first time it could be considered for encapsulation and the release of drugs. The nerve agent antidote 2-[(hydroxyiminomethyl]-1-methyl-pyridinium chloride (2-PAM or pralidoxime was effectively encapsulated into the pores of MIL-125-NH2 as a result of the interactions between 2-PAM and the pore walls being mediated by π-stacking and hydrogen bonds, as deduced from infrared spectroscopy and Monte Carlo simulation studies. Finally, colloidal solutions of MIL-125-NH2 nanoparticles exhibited remarkable stability in different organic media, aqueous solutions at different pH and under relevant physiological conditions over time (24 h. 2-PAM was rapidly released from the pores of MIL-125-NH2 in vitro.

  3. Preparation of magnetic MIL-101 (Cr) for efficient removal of ciprofloxacin.

    Bayazit, Şahika Sena; Danalıoğlu, Selen Tuğba; Abdel Salam, Mohamed; Kerkez Kuyumcu, Özge

    2017-11-01

    Metal organic frameworks are widely used as adsorbent materials in recent years. In this study, the most prepared metal organic framework MIL-101 was prepared by hydrothermal method and featured magnetic property using co-precipitation method Fe 3 O 4 . Then, the prepared composite (MIL-101/Fe 3 O 4 ) was first characterized using XRD, FTIR, SEM-EDS, and surface area analysis, then was used for the adsorptive removal of the most used antibiotic, ciprofloxacin (CIP). The effect of different adsorption variables which may affect the removal of CIP by MIL-101/Fe 3 O 4 was investigated, as well as their adsorbent quantity, initial CIP concentration, pH, temperature, and contact time. The non-linear Langmuir and Freundlich isotherm were applied to experimental data. It was observed that rising solution temperature decreases adsorption efficiency, as the maximum adsorption uptake value was 63.28 mg g -1 at 298 K and 22.93 mg g -1 at 313 K, indicating the exothermic nature of the adsorption. The adsorption was studied kinetically and found to follow the pseudo-second-order kinetic model. The desorption of CIP from the MIL-101/Fe 3 O 4 was investigated using three different eluents, and the results showed that phosphate-buffered solution was the most effective desorption eluent. Graphical abstract Schematic diagram of the preparation steps of MIL-101/Fe3O4.

  4. Nanometric MIL-125-NH₂ Metal-Organic Framework as a Potential Nerve Agent Antidote Carrier.

    Vilela, Sérgio M F; Salcedo-Abraira, Pablo; Colinet, Isabelle; Salles, Fabrice; de Koning, Martijn C; Joosen, Marloes J A; Serre, Christian; Horcajada, Patricia

    2017-10-12

    The three-dimensional (3D) microporous titanium aminoterephthalate MIL-125-NH₂ (MIL: Material of Institut Lavoisier) was successfully isolated as monodispersed nanoparticles, which are compatible with intravenous administration, by using a simple, safe and low-cost synthetic approach (100 °C/32 h under atmospheric pressure) so that for the first time it could be considered for encapsulation and the release of drugs. The nerve agent antidote 2-[(hydroxyimino)methyl]-1-methyl-pyridinium chloride (2-PAM or pralidoxime) was effectively encapsulated into the pores of MIL-125-NH₂ as a result of the interactions between 2-PAM and the pore walls being mediated by π-stacking and hydrogen bonds, as deduced from infrared spectroscopy and Monte Carlo simulation studies. Finally, colloidal solutions of MIL-125-NH₂ nanoparticles exhibited remarkable stability in different organic media, aqueous solutions at different pH and under relevant physiological conditions over time (24 h). 2-PAM was rapidly released from the pores of MIL-125-NH₂ in vitro.

  5. Understanding and solving disorder in the substitution pattern of amino functionalized MIL-47(V).

    Heinen, Jurn; Dubbeldam, David

    2016-03-14

    Electronic energies and elastic constants of four amino functionalized MIL-47(V) supercells were computed using plane wave density functional theory to determine the influence of the substituent positions on the organic linker. An inverse relationship between the ab initio energies and the elastic constants was found, indicating that the high electronic stability correlates with high mechanical stability. Torsion in all supercells was induced upon substitution, which caused strain in the NH2-MIL-47(V) supercell. The combined effect of the substituent bulkiness and the induced torsion reduced the pore volume of the NH2-MIL-47(V) structures by >7% and the surface area by >14% with respect to MIL-47(V). This reduction was confirmed by lower saturation capacities of methane, CO2 and benzene. When unfavourable substituent positions are chosen, large torsions caused a further reduction of the saturation capacity. Differences in surface area, pore volume and saturation capacity illustrate the importance of choosing the correct NH2-MIL-47(V) supercell.

  6. Demonstration of coupling correction below the per-mil limit in the LHC

    Maclean, Ewen Hamish; Fartoukh, Stephane; Persson, Tobias Hakan Bjorn; Skowronski, Piotr Krzysztof; Tomas Garcia, Rogelio; Wierichs, David Alexander; CERN. Geneva. ATS Department

    2016-01-01

    Linear coupling between betatron motion in the transverse planes is one of the key optics parameters for any accelerator. It can substantially affect the nonlinear dynamics, influencing both lifetime and the damping of instabilities, as well as affecting the ability to measure and control the linear optics. A review of published material revealed no account of coupling having been corrected significantly below the per-mil level in any hadron accelerator. This note reports the achievement of a sub-per-mil coupling correction during an LHC Machine Development study.

  7. Theoretical study of carbon dioxide adsorption and diffusion in MIL-127(Fe) metal organic framework

    Pongsajanukul, Pavee; Parasuk, Vudhichai; Fritzsche, Siegfried; Assabumrungrat, Suttichai; Wongsakulphasatch, Suwimol; Bovornratanaraks, Thiti; Chokbunpiam, Tatiya

    2017-07-01

    The UFF force field is found to reproduce the adsorption isotherm of carbon dioxide in MIL-127(Fe) well. It has therefore been used to investigate the structure and self-diffusion of carbon dioxide molecules in the MIL which is a candidate for membrane or adsorption application. The structure of the adsorbed phase shows different regions of high concentration. The highest particle concentration was found in the central regions of the channels. The self-diffusion coefficient slightly increases with the loading for low concentration of guest molecules while for higher concentrations it decreases because of mutual hindrance of guest molecules.

  8. Efficient Pd@MIL-101(Cr) hetero-catalysts for 2-butyne-1,4-diol hydrogenation exhibiting high selectivity

    Yin, Dongdong; Li, Chuang; Ren, Hangxing; Shekhah, Osama; Liu, Jinxuan; Liang, Changhai

    2017-01-01

    Pd@MIL-101(Cr) hetero-catalysts have been successfully prepared using the metal-organic chemical vapour deposition (MOCVD) approach, by choosing [Pd(η-CH)(η-CH)] as a volatile precursor, and the hydrothermally stable metal-organic framework, MIL-101

  9. Protonated MIL-125-NH2: Remarkable Adsorbent for the Removal of Quinoline and Indole from Liquid Fuel.

    Ahmed, Imteaz; Khan, Nazmul Abedin; Yoon, Ji Woong; Chang, Jong-San; Jhung, Sung Hwa

    2017-06-21

    The removal of nitrogen-containing compounds (NCCs) from fossil fuels prior to combustion is currently of particular importance, and so we investigated an adsorptive method using metal-organic frameworks (MOFs) for the removal of indole (IND) and quinoline (QUI), which are two of the main NCCs present in fossil fuels. We herein employed an amino (-NH 2 )-functionalized MIL-125 (MIL-125-NH 2 ) MOF, which was further modified by protonation (P-MIL-125-NH 2 ). These modified MOFs exhibited extraordinary performance in the adsorption of both IND (as representative neutral NCC) and QUI (as representative basic NCC). These MOFs were one of the most efficient adsorbents for the removal of NCCs. For example, P-MIL-125-NH 2 showed the highest adsorption capacity for QUI among ever reported adsorbent. The improved adsorption of IND was explained by H-bonding and cation-π interactions for MIL-125-NH 2 and P-MIL-125-NH 2 , respectively, while the mechanisms for QUI were H-bonding and acid-base interactions, respectively. This is a rare phenomenon for a single material (especially not with very high porosity) to exhibit such remarkable performances in the adsorption of both basic QUI and neutral IND. The adsorption results obtained using regenerated MIL-125-NH 2 and P-MIL-125-NH 2 also showed that these materials can be used several times without any severe degradation.

  10. Glucose recovery from aqueous solutions by adsorption in metal–organic framework MIL-101: a molecular simulation study

    Gupta, Krishna M.; Zhang, Kang; Jiang, Jianwen

    2015-01-01

    A molecular simulation study is reported on glucose recovery from aqueous solutions by adsorption in metal-organic framework MIL-101. The F atom of MIL-101 is identified to be the most favorable adsorption site. Among three MIL-101-X (X = H, NH2 or CH3), the parent MIL-101 exhibits the highest adsorption capacity and recovery efficacy. Upon functionalization by -NH2 or -CH3 group, the steric hindrance in MIL-101 increases; consequently, the interactions between glucose and framework become less attractive, thus reducing the capacity and mobility of glucose. The presence of ionic liquid, 1-ethyl-3-methyl-imidazolium acetate, as an impurity reduces the strength of hydrogen-bonding between glucose and MIL-101, and leads to lower capacity and mobility. Upon adding anti-solvent (ethanol or acetone), a similar adverse effect is observed. The simulation study provides useful structural and dynamic properties of glucose in MIL-101, and it suggests that MIL-101 might be a potential candidate for glucose recovery. PMID:26242874

  11. Glucose recovery from aqueous solutions by adsorption in metal-organic framework MIL-101: a molecular simulation study.

    Gupta, Krishna M; Zhang, Kang; Jiang, Jianwen

    2015-08-05

    A molecular simulation study is reported on glucose recovery from aqueous solutions by adsorption in metal-organic framework MIL-101. The F atom of MIL-101 is identified to be the most favorable adsorption site. Among three MIL-101-X (X = H, NH2 or CH3), the parent MIL-101 exhibits the highest adsorption capacity and recovery efficacy. Upon functionalization by -NH2 or -CH3 group, the steric hindrance in MIL-101 increases; consequently, the interactions between glucose and framework become less attractive, thus reducing the capacity and mobility of glucose. The presence of ionic liquid, 1-ethyl-3-methyl-imidazolium acetate, as an impurity reduces the strength of hydrogen-bonding between glucose and MIL-101, and leads to lower capacity and mobility. Upon adding anti-solvent (ethanol or acetone), a similar adverse effect is observed. The simulation study provides useful structural and dynamic properties of glucose in MIL-101, and it suggests that MIL-101 might be a potential candidate for glucose recovery.

  12. Efficient Pd@MIL-101(Cr) hetero-catalysts for 2-butyne-1,4-diol hydrogenation exhibiting high selectivity

    Yin, Dongdong

    2017-01-05

    Pd@MIL-101(Cr) hetero-catalysts have been successfully prepared using the metal-organic chemical vapour deposition (MOCVD) approach, by choosing [Pd(η-CH)(η-CH)] as a volatile precursor, and the hydrothermally stable metal-organic framework, MIL-101(Cr) as a support. The prepared Pd@MIL-101(Cr) hetero-catalysts characterized with various analytical techniques, exhibited highly monodispersed immobilized Pd nanoparticles in the MIL-101(Cr) cavities, while retaining the pristine crystallinity and porosity. The intact hybrid Pd@MIL-101(Cr) has been demonstrated to be an efficient catalyst for 2-butyne-1,4-diol hydrogenation with excellent activity, stability and selectivity (2-butene-1,4-diol (>94%)).

  13. MilQuant: a free, generic software tool for isobaric tagging-based quantitation.

    Zou, Xiao; Zhao, Minzhi; Shen, Hongyan; Zhao, Xuyang; Tong, Yuanpeng; Wang, Qingsong; Wei, Shicheng; Ji, Jianguo

    2012-09-18

    Isobaric tagging techniques such as iTRAQ and TMT are widely used in quantitative proteomics and especially useful for samples that demand in vitro labeling. Due to diversity in choices of MS acquisition approaches, identification algorithms, and relative abundance deduction strategies, researchers are faced with a plethora of possibilities when it comes to data analysis. However, the lack of generic and flexible software tool often makes it cumbersome for researchers to perform the analysis entirely as desired. In this paper, we present MilQuant, mzXML-based isobaric labeling quantitator, a pipeline of freely available programs that supports native acquisition files produced by all mass spectrometer types and collection approaches currently used in isobaric tagging based MS data collection. Moreover, aside from effective normalization and abundance ratio deduction algorithms, MilQuant exports various intermediate results along each step of the pipeline, making it easy for researchers to customize the analysis. The functionality of MilQuant was demonstrated by four distinct datasets from different laboratories. The compatibility and extendibility of MilQuant makes it a generic and flexible tool that can serve as a full solution to data analysis of isobaric tagging-based quantitation. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Ni foam-immobilized MIL-101(Cr) nanocrystals toward system integration for hydrogen storage

    Ren, Jianwei

    2015-10-01

    Full Text Available Metal–organic framework (MOF) materials are only obtained as loose powders with low packing density and thermal conductivity. To enable the developed MOF powdered materials to be utilized in a hydrogen storage system, in this study, MIL-101...

  15. Effect of Diamine in Amine-Functionalized MIL-101 for Knoevenagel Condensation

    Kasinathan, Palraj; Seo, You Kyong; Shim, Kyu Eun; Hwang, Young Kyu; Lee, U Hwang; Hwang, Dong Won; Hong, Do Young; Halligudi, Shiva B.; Chang, Jong San

    2011-01-01

    Have demonstrated that amines with different basicities successfully functionalized into the pores of MIL-101 and amine functionalized chromium terephthalate used as a base catalyst. The catalytic activity of amine functionalized MIL-101 in Knoevenagel condensation of ethylcyanoacetate and benzaldehyde depends on their basi-cities. The reactivity of these catalytic materials could be also affected by their pore size and/or surface area, which governs the facile diffusion of the molecules through the channels of the MIL-101. The present strategy ensures the development of new functionalities and lead to MOF applications of practically useful heterogeneous base catalysts for chemical transformations. Crystalline Metal-Organic Frameworks (MOFs) are currently an important kind of advanced functional materials due to their novel coordination structures, diverse topologies, and potential applications. As one of topical MOFs, porous chromium terephthalate with giant pores labeled MIL-101(Cr) possesses several unique features such as hierarchical pore structure including a mesoporous zeotype architecture, mesoporous cages and microporous windows, outstanding sorption properties, numerous unsaturated metal cation sites, and high hydrothermal and chemical stability. These properties have led to a number of application potential in catalysis, gas storage, drug delivery and adsorptive separation. One important challenge has to realize is funtionalization via incorporation of binding site or reactive centers for catalysis. The functionalization methods of metal organic frameworks (MOFs) in a wide range of applications are two possible approaches including pre- and post-modification with functional groups

  16. MIL-L-87177 and CLT:X-10 Lubricants Improve Electrical Connector Fretting Corrosion Behavior

    AUKLAND, NEIL R.; HANLON, JAMES T.

    1999-01-01

    We have conducted a fretting research project using MIL-L-87177 and CLT: X-10 lubricants on Nano-miniature connectors. When they were fretted without lubricant, individual connectors first exceeded our 0.5 ohm failure criteria from 2,341 to 45,238 fretting cycles. With additional fretting, their contact resistance increased to more than 100,000 ohms. Unmodified MIL-L-87177 lubricant delayed the onset of first failure to between 430,000 and over 20,000,000 fretting cycles. MIL-L-87177 modified by addition of Teflon powder delayed first failure to beyond 5 million fretting cycles. Best results were obtained when Teflon was used and also when both the straight and modified lubricants were poured into and then out of the connector. CLT: X-10 lubricant delayed the onset of first failure to beyond 55 million cycles in one test where a failure was actually observed and to beyond 20 million cycles in another that was terminated without failure. CLT: X-10 recovered an unlubricated connector driven deeply into failure, with six failed pins recovering immediately and four more recovering during an additional 420 thousand fretting cycles. MIL-L-87177 was not able to recover a connector under similar conditions

  17. Effect of synthesis solvent on the breathing behavior of MIL-53(Al).

    Mounfield, William P; Walton, Krista S

    2015-06-01

    This work reports the effect of using dimethylformamide (DMF) as the solvent for synthesizing MIL-53(Al). This well-known breathing MOF is typically prepared using hydrothermal methods. The two materials synthesized in DMF at 120°C and 220°C show significant deviations from the breathing behavior exhibited by the material synthesized hydrothermally. Powder X-ray diffraction confirmed that MIL-53(Al) synthesized in DMF at 120°C remains in the large-pore form under all conditions, while the other material synthesized at 220°C undergoes a more gradual breathing transition than is observed for MIL-53(Al) prepared by traditional methods. Solid-state NMR was employed to elucidate additional structural information and gain insight into the role synthesis solvent plays on breathing behavior. The CO2 and water adsorption of these large-pore stabilized materials were studied, and the differences in adsorption behavior compared to MIL-53(Al) prepared by traditional methods was discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Mil doscientos títulos de antropología colombiana: primera parte

    Manuel Lucena Salmoral

    1969-08-01

    Full Text Available La aparición de estos mil doscientos títulos sobre antropología Colombiana representa un esfuerzo juvenil de universitarios javerianos, pertenecientes a distintas ciencias sociales, quienes fueron confluyendo a mis clases de Antropología Cultural guiados por la misma problemática: la búsqueda del hombre.

  19. B-1 Aircraft Main Hydraulic Pump Tests With MIL-H-87257 Hydraulic Fluid

    Sharma, Shashi

    1998-01-01

    In an effort to convert the B-1 aircraft from MIL-H-5606 to M1-H-87257, the Air Force sponsored a study conducted by Rockwell International from April 1991 through June 1992, under contract F34601-89-C-0401...

  20. Hydrogen selective NH{sub 2}-MIL-53(Al) MOF membranes with high permeability

    Zhang, Feng; Zou, Xiaoqin; Gao, Xue; Fan, Songjie; Sun, Fuxing; Ren, Hao; Zhu, Guangshan [State Key Laboratory of Inorganic, Synthesis and Preparative Chemistry, Jilin University, Changchun (China)

    2012-09-11

    Hydrogen-based energy is a promising renewable and clean resource. Thus, hydrogen selective microporous membranes with high performance and high stability are demanded. Novel NH{sub 2}-MIL-53(Al) membranes are evaluated for hydrogen separation for this goal. Continuous NH{sub 2}-MIL-53(Al) membranes have been prepared successfully on macroporous glass frit discs assisted with colloidal seeds. The gas sorption ability of NH{sub 2}-MIL-53(Al) materials is studied by gas adsorption measurement. The isosteric heats of adsorption in a sequence of CO{sub 2}> N{sub 2}> CH{sub 4}{approx} H{sub 2} indicates different interactions between NH{sub 2}-MIL-53(Al) framework and these gases. As-prepared membranes are measured by single and binary gas permeation at different temperatures. The results of singe gas permeation show a decreasing permeance in an order of H{sub 2}> CH{sub 4}> N{sub 2}> CO{sub 2}, suggesting that the diffusion and adsorption properties make significant contributions in the gas permeation through the membrane. In binary gas permeation, the NH{sub 2}-MIL-53(Al) membrane shows high selectivity for H{sub 2} with separation factors of 20.7, 23.9 and 30.9 at room temperature (288 K) for H{sub 2} over CH{sub 4}, N{sub 2} and CO{sub 2}, respectively. In comparison to single gas permeation, a slightly higher separation factor is obtained due to the competitive adsorption effect between the gases in the porous MOF membrane. Additionally, the NH{sub 2}-MIL-53(Al) membrane exhibits very high permeance for H{sub 2} in the mixtures separation (above 1.5 x 10{sup -6} mol m{sup -2} s{sup -1} Pa{sup -1}) due to its large cavity, resulting in a very high separation power. The details of the temperature effect on the permeances of H{sub 2} over other gases are investigated from 288 to 353 K. The supported NH{sub 2}-MIL-53(Al) membranes with high hydrogen separation power possess high stability, resistance to cracking, temperature cycling and show high reproducibility

  1. Comparative Study of MIL-96(Al) as Continuous Metal-Organic Frameworks Layer and Mixed-Matrix Membrane.

    Knebel, Alexander; Friebe, Sebastian; Bigall, Nadja Carola; Benzaqui, Marvin; Serre, Christian; Caro, Jürgen

    2016-03-23

    MIL-96(Al) layers were prepared as supported metal-organic frameworks membrane via reactive seeding using the α-alumina support as the Al source for the formation of the MIL-96(Al) seeds. Depending on the solvent mixture employed during seed formation, two different crystal morphologies, with different orientation of the transport-active channels, have been formed. This crystal orientation and habit is predefined by the seed crystals and is kept in the subsequent growth of the seeds to continuous layers. In the gas separation of an equimolar H2/CO2 mixture, the hydrogen permeability of the two supported MIL-96(Al) layers was found to be highly dependent on the crystal morphology and the accompanied channel orientation in the layer. In addition to the neat supported MIL-96(Al) membrane layers, mixed-matrix membranes (MMMs, 10 wt % filler loading) as a composite of MIL-96(Al) particles as filler in a continuous Matrimid polymer phase have been prepared. Five particle sizes of MIL-96(Al) between 3.2 μm and 55 nm were synthesized. In the preparation of the MIL-96(Al)/Matrimid MMM (10 wt % filler loading), the following preparation problems have been identified: The bigger micrometer-sized MIL-96(Al) crystals show a trend toward sedimentation during casting of the MMM, whereas for nanoparticles aggregation and recrystallization to micrometer-sized MIL-96(Al) crystals has been observed. Because of these preparation problems for MMM, the neat supported MIL-96(Al) layers show a relatively high H2/CO2 selectivity (≈9) and a hydrogen permeance approximately 2 magnitudes higher than that of the best MMM.

  2. Anti-UV Radiation Textiles Designed by Embracing with Nano-MIL (Ti, In)-Metal Organic Framework.

    Emam, Hossam E; Abdelhameed, Reda M

    2017-08-23

    Protective textiles against harmful solar radiation are quite important materials for outdoor workers to secure their skin from several diseases. Current report focuses on production of anti-ultraviolet radiation (UVR) textiles by incorporation of nano-metal-organic frameworks (n-MOFs). Two different MIL-MOFs, namely, MIL-68(In)-NH 2 and MIL-125(Ti)-NH 2 , were immediately formed inside natural textiles (cotton and silk) matrix in nano size using quite simple and one-pot process. The formation of n-MIL-MOFs inside textiles were confirmed by using electron microscope and X-ray diffraction. Different size and morphology were seen depending on textile type reflecting the textiles' chemical composition role in the nature of prepared MIL-MOFs. For MIL-68(In)-NH 2 , particles with size distribution of 70.6-44.5 nm in cotton and 81.3-52.2 nm in silk were detected, while crystalline disc of MIL-125(Ti)-NH 2 was clearly seen inside textiles. The natural textiles exhibited full UVR blocking after modification, and the UV protection factor (UPF) was linearly proportional with MIL-MOFs and metal contents. Whatever metal type, direct incorporation of MIL-MOF contents greater than or equal to 10.4 g/kg was sufficient to attain excellent UV blocking property. Although 38.5-41.0% of MIL-MOFs was lost during five washings, the washed samples showed very good blocking rate (UPF = 26.7-36.2) supporting good laundering durability.

  3. Enhancing the water stability of Al-MIL-101-NH2 via postsynthetic modification.

    Wittmann, Thomas; Siegel, Renée; Reimer, Nele; Milius, Wolfgang; Stock, Norbert; Senker, Jürgen

    2015-01-02

    The resistance of metal-organic frameworks towards water is a very critical issue concerning their practical use. Recently, it was shown for microporous MOFs that the water stability could be increased by introducing hydrophobic pendant groups. Here, we demonstrate a remarkable stabilisation of the mesoporous MOF Al-MIL-101-NH2 by postsynthetic modification with phenyl isocyanate. In this process 86 % of the amino groups were converted into phenylurea units. As a consequence, the long-term stability of Al-MIL-101-URPh in liquid water could be extended beyond a week. In water saturated atmospheres Al-MIL-101-URPh decomposed at least 12-times slower than the unfunctionalised analogue. To study the underlying processes both materials were characterised by Ar, N2 and H2 O sorption measurements, powder X-ray diffraction, thermogravimetric and chemical analysis as well as solid-state NMR and IR spectroscopy. Postsynthetic modification decreased the BET equivalent surface area from 3363 to 1555 m(2)  g(-1) for Al-MIL-101-URPh and reduced the mean diameters of the mesopores by 0.6 nm without degrading the structure significantly and reducing thermal stability. In spite of similar water uptake capacities, the relative humidity-dependent uptake of Al-MIL-101-URPh is slowed and occurs at higher relative humidity values. In combination with (1) H-(27) Al D-HMQC NMR spectroscopy experiments this favours a shielding mechanism of the Al clusters by the pendant phenyl groups and rules out pore blocking. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Novel thymine-functionalized MIL-101 prepared by post-synthesis and enhanced removal of Hg(2+) from water.

    Luo, Xubiao; Shen, Tingting; Ding, Lin; Zhong, Weiping; Luo, Jianfeng; Luo, Shenglian

    2016-04-05

    A novel thymine-functionalized MIL-101 (MIL-101-Thymine) material was synthesized using a post-synthesis method to remove mercury at a high efficiency. MIL-101-Thymine was successfully prepared in this work and was confirmed by several characterization methods, such as (13)C nuclear magnetic resonance, X-ray diffraction, and infrared spectroscopy. The Hg(2+) adsorption agreed well with the Langmuir model, and the maximum adsorption capacity was 51.27mg/g. The adsorption rate fit with the pseudo-second-order kinetic model. Furthermore, MIL-101-Thymine exhibited excellent selectivity towards Hg(2+) over other cations, and the maximum value of the selective coefficient reached 947.34; this result is very likely due to the highly selective interactions of T-Hg(2+)-T in MIL-101-Thymine. The result of X-ray photoelectron spectroscopy also showed that Hg(2+) was coordinated with the N of thymine in MIL-101-Thymine. Moreover, the results of the thermogravimetric analysis and adsorption experiments showed that the Hg atom was two-coordinated with the thymine group. MIL-101-Thymine was used to remove trace Hg(2+) in real water samples, and satisfactory recoveries were obtained. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. The metal-organic framework MIL-53(Al) constructed from multiple metal sources: alumina, aluminum hydroxide, and boehmite.

    Li, Zehua; Wu, Yi-nan; Li, Jie; Zhang, Yiming; Zou, Xin; Li, Fengting

    2015-04-27

    Three aluminum compounds, namely alumina, aluminum hydroxide, and boehmite, are probed as the metal sources for the hydrothermal synthesis of a typical metal-organic framework MIL-53(Al). The process exhibits enhanced synthetic efficiency without the generation of strongly acidic byproducts. The time-course monitoring of conversion from different aluminum sources into MIL-53(Al) is achieved by multiple characterization that reveals a similar but differentiated crystallinity, porosity, and morphology relative to typical MIL-53(Al) prepared from water-soluble aluminum salts. Moreover, the prepared MIL-53(Al) constructed with the three insoluble aluminum sources exhibit an improved thermal stability of up to nearly 600 °C and enhanced yields. Alumina and boehmite are more preferable than aluminum hydroxide in terms of product porosity, yield, and reaction time. The adsorption performances of a typical environmental endocrine disruptor, dimethyl phthalate, on the prepared MIL-53(Al) samples are also investigated. The improved structural stability of MIL-53(Al) prepared from these alternative aluminum sources enables double-enhanced adsorption performance (up to 206 mg g(-1)) relative to the conventionally obtained MIL-53(Al). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Effective Adsorption and Removal of Phosphate from Aqueous Solutions and Eutrophic Water by Fe-based MOFs of MIL-101.

    Xie, Qiying; Li, Yan; Lv, Zhaoling; Zhou, Hang; Yang, Xiangjun; Chen, Jing; Guo, Hong

    2017-06-12

    Although many efforts have been devoted to the adsorptive removal of phosphate from aqueous solutions and eutrophic water, it is still highly desirable to develop novel adsorbents with high adsorption capacities. In this study, Fe-based metal-organic frameworks (MOFs), MIL-101 and NH 2 -MIL-101, are fabricated through a general facile strategy. Their performance as an adsorbent for phosphate removal is investigated. Experiments are performed to study the effects of various factors on the phosphate adsorption, including adsorbent dosage, contact time and co-existing ions. Both MIL-101(Fe) and NH 2 -MIL-101(Fe) show highly effective removal of phosphates from aqueous solutions, and the concentration of phosphates decrease sharply from the initial 0.60 mg·L -1 to 0.045 and 0.032 mg·L -1 , respectively, within just 30 min of exposure. The adsorption kinetics and adsorption isotherms reveal that NH 2 -MIL-101(Fe) has higher adsorption capacity than MIL-101(Fe) possibly due to the amine group. Furthermore, the Fe-based MOFs also exhibit a high selectivity towards phosphate over other anions such as chloride, bromide, nitrate and sulfate. Particularly, the prepared Fe-based MIL-101 materials are also capable of adsorbing phosphate in an actual eutrophic water sample and display better removal effect.

  7. Glycine post-synthetic modification of MIL-53(Fe) metal-organic framework with enhanced and stable peroxidase-like activity for sensitive glucose biosensing.

    Dong, Wenfei; Yang, Liaoyuan; Huang, Yuming

    2017-05-15

    A facile and rapid post-synthetic strategy was proposed to prepare a glycine functionalized MIL-53(Fe), namely glycine-MIL-53(Fe), by a simple mixing of water dispersible MIL-53(Fe) and glycine. The FT-IR, SEM, XRD and zeta potential were used to characterize the glycine-MIL-53(Fe). The result showed that glycine post-synthetic modification of MIL-53(Fe) did not change in the morphology and crystal structure of MIL-53(Fe). Interestingly, compared with MIL-53(Fe), the glycine-MIL-53(Fe) exhibits an enhanced peroxidase-like activity, which could catalyze the oxidation of TMB by H 2 O 2 to produce an intensive color reaction. Kinetic analysis indicated that the K m of glycine-MIL-53(Fe) for TMB was one-tenth of that of MIL-53(Fe). The glycine-MIL-53(Fe) as peroxidase mimetic displays better stability under alkaline or acidic conditions than MIL-53(Fe). The good performance of glycine-MIL-53(Fe) over MIL-53(Fe) may be attributed to the increase of affinity between TMB and the glycine-MIL-53(Fe). With these characteristics, a simple and sensitive method was developed for the detection of H 2 O 2 and glucose. The linear detection range for H 2 O 2 is 0.10-10μM with a detection limit of 49nM, and glucose could be linearly detected in the range from 0.25 to 10μM with a detection limit of 0.13μM. The proposed method was successfully used for glucose detection in human serum samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. MIL-STD-1553B Marconi LSI chip set in a remote terminal application

    Dimarino, A.

    1982-11-01

    Marconi Avionics is utilizing the MIL-STD-1553B LSI Chip Set in the SCADC Air Data Computer application to perform all of the required remote terminal MIL-STD-1553B protocol functions. Basic components of the RTU are the dual redundant chip set, CT3231 Transceivers, 256 x 16 RAM and a Z8002 microprocessor. Basic transfers are to/from the RAM command of the bus controller or Z8002 processor. During transfers from the processor to the RAM, the chip set busy bit is set for a period not exceeding 250 microseconds. When the transfer is complete, the busy bit is released and transfers to the data bus occur on command. The LSI Chip Set word count lines are used to locate each data word in the local memory and 4 mode codes are used in the application: reset remote terminal, transmit status word, transmitter shut-down, and override transmitter shutdown.

  9. Electro-Synthetic Optimization of Host Material Based on MIL-100(Fe

    Witri Wahyu Lestari

    2016-05-01

    Full Text Available Electro-synthesis of Metal-Organic Frameworks types of MIL-100(Fe (MIL = Material Institute of Lavoisier in ethanol: water (1: 1 with electrolyte TBATFB 0.1 M has been optimized by varying voltage (12, 13, 14 and 15 Volt and temperature (room temperature, 40, 60 and 80 °C. The product showed light brown powder which upon activation becomes dark brown. Optimum condition achieved during use voltage of 15 Volts and at a temperature of 40 °C with 33% yield. The obtained material was characterized by XRD and compared to CCDC 640536 simulated patterns to confirm the phase purity of the product. As comparison hydrothermal and reflux method have been carried out. Characterization by FTIR has also undertaken to ensure the coordination between the metal cation (Fe3+ and the BTC ligand (BTC = 1,3,5-Benzene Tri Carboxylate. Meanwhile pore analysis using SAA confirmed that MIL-100(Fe obtained by electrolysis method has a BET surface area reached till 569.191 m²/g with a total pore volume of 0.4540 cc/g and an average pore diameter reached 16 Å. Based on SEM analysis, morphology material show particle size between 0.4-8.6 μm and has a thermal stability up to 350 °C according thermo-gravimetric analysis. Due to the presence of Lewis acid sites on Fe-trimeric unit, porosity features on MIL-100(Fe and a fairly high thermal stability, this material is potentially used as the host material for the catalyst in the conversion reactions model for green diesel production.

  10. ENHANCEMENT OF ACIDITY AND CATALYTIC ACTIVITY OF ALUMINA BASED METAL ORGANIC FRAMEWORK (MIL-53 Al)

    Yilmaz, Esra; Sert, Emine; Atalay, Ferhan Sami

    2017-01-01

    Metal organic frameworks are highly porous materials which are formed bycombination of metal precursor and salts as inorganic part and ligand asorganic part. They have many advantages such as low density, high surface area,tunable pore size and high porosity. Due to peculiar features, such asunsaturated metal active sites, high surface area and easily functionalization,its usage as catalyst are promising.  The MIL-53(Al) structure contains chains of transcorner-sharing [AlO4(OH)2] oc...

  11. Software support for Motorola 68000 microprocessor at CERN. M68MIL cross macro assembler

    Eicken, H. von.

    1983-01-01

    This document is a user's guide for programming the Motorola 68000 microprocessor in assembly language. It describes the programming model, addressing modes and instruction set of the M 68000 as well as the use of the M68mil cross macro assembler. Version 3.6 of the assembler has been installed at CERN on CDC, DEC VAX, IBM, Norsk Data and Siemens computers. The source code of the assembler is available from CERN on request. (orig.)

  12. MIL-STD-2411-1 Change 3. Notice Impacts to NAVAIR

    2010-07-30

    Macedonia ZX Macais Nguema Biyogo MA Madagascar VD Madeira Islands (PO) MI Malawi MY Malaysia MV Maldives ML Mali MT Malta IM Isle of Man (UK) MIL...and Niger) PON Pointe Noire 1948 (Congo) POS Porto Santo 1936 (Porto Santo, Madeira Islands) HIT Prov. S. Chilean (S. Chile, 53 S.) PRPM Prov. S...Asia (Southeast Asia, Singapore) POS SE Base (Porte Santo) (Porto Santo & Madeira Islands) GRA SW Base (Faial, Graciosa, Pico, Sao Jorge, and

  13. HKUST-1 Membranes Anchored on Porous Substrate by Hetero MIL-110 Nanorod Array Seeds.

    Mao, Yiyin; Cao, Wei; Li, Junwei; Sun, Luwei; Peng, Xinsheng

    2013-09-02

    Great anchors and seeds: Hetero-seeding growth processes and anchored nanorod arrays were successfully utilized in the synthesis of HKUST-1 membranes. These arrays were firmly anchored on porous substrates by using a MIL-110 nanorod array as both the anchor and seed. The resulting HKUST-1 membranes demonstrated good separation factors for binary gases exceeding the Knudson selectivity. Copyright © 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Edificio de viviendas. Ca´Granda, Milán

    Gandolfi, Vittorio

    1959-04-01

    Full Text Available Con el nombre de "Ca'Granda" se ha querido designar el distrito, capaz de 6.000 habitantes, que el Ayuntamiento de Milán está construyendo, y en parte ha construido ya, en la zona detrás de las calles Fulvio Testi y Ospedale Maggiore; es decir, en el sector norte de la ciudad correspondiente a la dirección de mayor impulso del desarrollo urbanístico de lo habitado.

  15. The studies on gas adsorption properties of MIL-53 series MOFs materials

    Yuqiu Jiao

    2017-08-01

    Full Text Available Molecular dynamics (MD, grand canonical Monte Carlo (GCMC and ideal adsorbed solution theory (IAST were used to study the structures and gas adsorption properties of MIL-53(M[M=Cr, Fe, Sc, Al] metal organic framework (MOF materials. The results show that the volumes of those MOF materials increase significantly at high temperature. By analyzing the adsorption isotherms, we found that the temperature had a paramount effect on the gas adsorption behaviors of these MOF materials. For MIL-53(Cr, the orders of the quantities of adsorbed gases were CH4>N2>CO2>H2S, CH4>H2S>CO2>N2 and CH4>CO2>H2S>N2 at 100K, 293K and 623K, respectively. We also calculated the adsorption of several combinations of two gases by MIL-53(Cr at 293K, the results indicate that the material had selective adsorption of CH4 over CO2, H2S and N2. Our calculations provide microscopic insights into the gas adsorption performances of these MOFs and may further guide the practice of gas separation.

  16. Evaluation of electrical test conditions in MIL-M-38510 slash sheets

    Sandgren, K.

    1980-08-01

    Adequacy of MIL-M-38510 slash sheet requirements for electrical test conditions in an automated test environment were evaluated. Military temperature range commercial devices of 13 types from 6 manufacturers were purchased. Software for testing these devices and for varying the test conditions was written for the Tektronix S-3260 test system. The devices were tested to evaluate the effects of pin-condition settling time, measurement sequence of the same and different D-C parameters, temperature sequence, differently defined temperature ambients, variable measurement conditions, sequence of time measurements, pin-application sequence, and undesignated pin condition ambiguity. An alternative to current tri-state enable and disable time measurements is proposed; S-3260 'open' and 'ground' conditions are characterized; and suggestions for changes in MIL-M-38510 slash sheet specifications and MIL-STD-883 test methods are proposed, both to correct errors and ambiguities and to facilitate the gathering of repeatable data on automated test equipment. Data obtained showed no sensitivity to measurement or temperature sequence nor to temperature ambient, provided that test times were not excessive. V sub ICP tests and some low current measurements required allowance for a pin condition settling time because of the test system speed. Some pin condition application sequences yielded incorrect measurements. Undefined terminal conditions of output pins were found to affect I sub OS and propagation delay time measurements. Truth table test results varied with test frequency and V sub IL for low-power Schottky devices.

  17. The studies on gas adsorption properties of MIL-53 series MOFs materials

    Jiao, Yuqiu; Li, Zhenyu; Ma, Yue; Zhou, Guanggang; Wang, Shuangxi; Lu, Guiwu

    2017-08-01

    Molecular dynamics (MD), grand canonical Monte Carlo (GCMC) and ideal adsorbed solution theory (IAST) were used to study the structures and gas adsorption properties of MIL-53(M)[M=Cr, Fe, Sc, Al] metal organic framework (MOF) materials. The results show that the volumes of those MOF materials increase significantly at high temperature. By analyzing the adsorption isotherms, we found that the temperature had a paramount effect on the gas adsorption behaviors of these MOF materials. For MIL-53(Cr), the orders of the quantities of adsorbed gases were CH4>N2>CO2>H2S, CH4>H2S>CO2>N2 and CH4>CO2>H2S>N2 at 100K, 293K and 623K, respectively. We also calculated the adsorption of several combinations of two gases by MIL-53(Cr) at 293K, the results indicate that the material had selective adsorption of CH4 over CO2, H2S and N2. Our calculations provide microscopic insights into the gas adsorption performances of these MOFs and may further guide the practice of gas separation.

  18. Trivalent Chromium Process (TCP) as a Sealer for MIL-A-8625F Type II, IIB, and IC Anodic Coatings

    Matzdorf, Craig; Beck, Erin; Hilgeman, Amy; Prado, Ruben

    2008-01-01

    This report documents evaluations of trivalent chromium compositions (TCP) as sealers for MIL-A-8625F Type II, IIB, and IC anodic coatings conducted from March 2001 through December 2007 by Materials Engineering...

  19. Intermodal Storage and Transport Frame (ISTF) MIL-STD-1660 Design Criteria for Ammunition Unit Loads Tests

    Barickman, Philip

    2004-01-01

    .... The ISTF was evaluated by the testing procedures set forth in MIL-STD-1660. Stacking, vibration, edgewise rotational drop, incline impact, sling compatibility, forklifting, and disassembly testing were conducted on the ISTF units...

  20. Purification of Contaminated MIL-PRF-83282 Hydraulic Fluid Using the Pall Purifier and Multiple Process Configurations (Preprint)

    Snyder, Jr., Carl E; Gschwender, Lois J; Gunderson, Stephen L; Fultz, George W

    2006-01-01

    .... This report describes a project that evaluated the effectiveness of various hydraulic fluid purification process configurations on the removal of water and particulate contaminants from MIL-PRF-83282...

  1. PA171 Containers on a Wood Pallet with Metal Top Adapter, Air Pressure Tests During MIL-STD-1660 Tests

    2004-01-01

    ... (PM-MAS) to conduct Air Pressure Tests during MIL-STD-1660, "Design Criteria for Ammunition Unit Loads" testing on the PA171 containers on a wood pallet with metal top adapter as manufactured by Alliant Tech...

  2. Petits mils, énorme potentiel : diversifiés, nutritifs et adaptés aux ...

    29 avr. 2016 ... La culture des petits mils en complément des cultures existantes ... Redynamiser la production de petits mils pourrait améliorer la nutrition et la santé en Inde, ... que nécessite leur transformation et de la perception négative que l'on en ... Increasing gender equality among small millet farmers in South Asia.

  3. Metal-organic frameworks as potential shock absorbers: the case of the highly flexible MIL-53(Al).

    Yot, Pascal G; Boudene, Zoubeyr; Macia, Jasmine; Granier, Dominique; Vanduyfhuys, Louis; Verstraelen, Toon; Van Speybroeck, Veronique; Devic, Thomas; Serre, Christian; Férey, Gérard; Stock, Norbert; Maurin, Guillaume

    2014-08-28

    The mechanical energy absorption ability of the highly flexible MIL-53(Al) MOF material was explored using a combination of experiments and molecular simulations. A pressure-induced transition between the large pore and the closed pore forms of this solid was revealed to be irreversible and associated with a relatively large energy absorption capacity. Both features make MIL-53(Al) the first potential MOF candidate for further use as a shock absorber.

  4. Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc Welding Process

    2013-05-23

    further. Application of the Scheil additive rule to MIL A46100 yielded the CCT diagram displayed in Fig. 8. The diagram displayed in Fig. 8 is obtained...computational procedure used to construct the TTTand CCT diagrams could be used to predict the incubation time for austenite decomposition under an...of austenite into allotriomorphic ferrite is Fig. 8 MIL A46100 CCT diagram corresponding to the TTT dia- gram displayed in Figure 7(a): CCT curves and

  5. Gestion intégrée du mildiou du mil en station au centre régional de ...

    user

    Le mil (Pennicetum glaucum) L.R.Br constitue 75% de la production céréalière du Niger. Cependant, son rendement est très faible dû à plusieurs types de contraintes. La maladie du mildiou du mil causé par un champignon Sclerospora graminicola (Sacc) Schroët, occupe une place importante. L'objectif de cette étude.

  6. Atomic Layer Deposition of Pt Nanoparticles within the Cages of MIL-101: A Mild and Recyclable Hydrogenation Catalyst

    Karen Leus

    2016-03-01

    Full Text Available We present the in situ synthesis of Pt nanoparticles within MIL-101-Cr (MIL = Materials Institute Lavoisier by means of atomic layer deposition (ALD. The obtained Pt@MIL-101 materials were characterized by means of N2 adsorption and X-ray powder diffraction (XRPD measurements, showing that the structure of the metal organic framework was well preserved during the ALD deposition. X-ray fluorescence (XRF and transmission electron microscopy (TEM analysis confirmed the deposition of highly dispersed Pt nanoparticles with sizes determined by the MIL-101-Cr pore sizes and with an increased Pt loading for an increasing number of ALD cycles. The Pt@MIL-101 material was examined as catalyst in the hydrogenation of different linear and cyclic olefins at room temperature, showing full conversion for each substrate. Moreover, even under solvent free conditions, full conversion of the substrate was observed. A high concentration test has been performed showing that the Pt@MIL-101 is stable for a long reaction time without loss of activity, crystallinity and with very low Pt leaching.

  7. Chromium-based metal-organic framework MIL-101 as a highly effective catalyst in plasma for toluene removal

    Wu, Junliang; Xia, Qibin; Xiao, Jing; Li, Zhong

    2017-11-01

    Catalytic performance of MIL-101—a type of chromium-based metal-organic frameworks (MOFs)—in a plasma catalysis system for toluene removal was experimentally studied. The MIL-101 was synthesized using a hydrothermal method, and its catalytic performance was compared to two other catalysts, Cr2O3/γ-Al2O3 and γ-Al2O3, in a dielectric barrier discharge (DBD) reactor. Results showed that the presence of a catalyst in plasma changed the voltage and current characteristic substantially, and promoted the performance of the plasma reactor. Among the catalysts, the MIL-101 exhibited a significantly high toluene conversion, which was 20% and 35% higher than Cr2O3/γ-Al2O3 and γ-Al2O3, respectively, under the same testing conditions, as well as higher carbon balance and CO2 selectivity. The analysis of by-products on the surfaces of the catalysts before and after reaction demonstrated that MIL-101 had better resistance towards by-products accumulation compared to Cr2O3/γ-Al2O3 and γ-Al2O3. The loading of MnO x on MIL-101 further promoted its catalytic performance. MIL-101 exhibits attractive catalytic properties as a catalyst in a plasma catalysis system for the decomposition of volatile organic compounds.

  8. Chromium-based metal-organic framework MIL-101 as a highly effective catalyst in plasma for toluene removal

    Wu, Junliang; Xia, Qibin; Xiao, Jing; Li, Zhong

    2017-01-01

    Catalytic performance of MIL-101—a type of chromium-based metal-organic frameworks (MOFs)—in a plasma catalysis system for toluene removal was experimentally studied. The MIL-101 was synthesized using a hydrothermal method, and its catalytic performance was compared to two other catalysts, Cr 2 O 3 / γ -Al 2 O 3 and γ -Al 2 O 3 , in a dielectric barrier discharge (DBD) reactor. Results showed that the presence of a catalyst in plasma changed the voltage and current characteristic substantially, and promoted the performance of the plasma reactor. Among the catalysts, the MIL-101 exhibited a significantly high toluene conversion, which was 20% and 35% higher than Cr 2 O 3 / γ -Al 2 O 3 and γ -Al 2 O 3 , respectively, under the same testing conditions, as well as higher carbon balance and CO 2 selectivity. The analysis of by-products on the surfaces of the catalysts before and after reaction demonstrated that MIL-101 had better resistance towards by-products accumulation compared to Cr 2 O 3 / γ -Al 2 O 3 and γ -Al 2 O 3 . The loading of MnO x on MIL-101 further promoted its catalytic performance. MIL-101 exhibits attractive catalytic properties as a catalyst in a plasma catalysis system for the decomposition of volatile organic compounds. (paper)

  9. Host-guest interaction of styrene and ethylbenzene in MIL-53 studied by solid-state NMR.

    Li, Shenhui; Li, Jing; Tang, Jing; Deng, Feng

    Solid-state NMR was utilized to explore the host-guest interaction between adsorbate and adsorbent at atomic level to understand the separation mechanism of styrene (St) and ethylbenzene (EB) in MIL-53(Al). 13 C- 27 Al double-resonance NMR experiments revealed that the host-guest interaction between St and MIL-53 was much stronger than that of EB adsorption. In addition, 13 C DIPSHIFT experiments suggested that the adsorbed St was less mobile than EB confined inside the MIL-53 pore. Furthermore, the host-guest interaction model between St, EB and MIL-53 was established on the basis of the spatial proximities information extracted from 2D 1 H- 1 H homo-nuclear correlation NMR experiments. According to the experimental observation from solid-state NMR, it was found that the presence of π-π interaction between St and MIL-53 resulted in the stronger host-guest interaction and less mobility of St. This work provides direct experimental evidence for understanding the separation mechanism of St and EB using MIL-53 as an adsorbent. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Structure and properties of Al-MIL-53-ADP, a breathing MOF based on the aliphatic linker molecule adipic acid.

    Reinsch, Helge; Pillai, Renjith S; Siegel, Renée; Senker, Jürgen; Lieb, Alexandra; Maurin, Guillaume; Stock, Norbert

    2016-03-14

    The new aluminium based metal-organic framework [Al(OH)(O2C-C4H8-CO2)]·H2O denoted as Al-MIL-53-ADP-lp (lp stands for large pore) was synthesised under solvothermal conditions. This solid is an analogue of the archetypical aluminium terephthalate Al-MIL-53 based on the aliphatic single-chain linker molecule adipic acid (H2ADP, hexanedioic acid). In contrast to its aromatic counterparts, Al-MIL-53-ADP exhibits a structural breathing behaviour solely upon dehydration/rehydration. The crystal structure of the anhydrous compound denoted as Al-MIL-53-ADP-np (np stands for narrow pore) was determined by a combination of forcefield-based computations and Rietveld refinement of the powder X-ray diffraction data while the structure of the hydrated form Al-MIL-53-ADP-lp was derived computationally by a combination of force field based methods and Density Functional Theory calculations. Both structures were further supported by (1)H, (13)C and (27)Al high-resolution NMR MAS 1D data coupled again with simulations. Al-MIL-53-ADP was further characterised by means of vibrational spectroscopy, elemental analysis, thermogravimetry and water vapour sorption.

  11. Catalytic Performance of Microwave Functionalized NH2-MIL-53 for Cyclic Carbonate Synthesis from CO2 and Epoxides.

    Seok, Han-Geul; Kim, Dong-Woo; Yang, Jeung-Gyu; Kim, Moon-Il; Park, Dae-Won

    2016-05-01

    The efficacy of microwave irradiation in the quaternization of amino-functionalized MIL-53 metal-organic framework (MOF) as well as the catalytic activity of the resultant MOF in the cycloaddition of carbon dioxide with epoxides under solvent-free conditions has been studied. A series of NH2-MIL-53 were synthesized and quaternized by reacting alkyl halide of various alkyl chains and anions under microwave irradiation. The post-functionalized F-MIL-53-AXs were characterized through solid-state XRD, FT-IR, XPS, and TGA. F-MIL-53-Mel prepared by microwave method showed higher AGC yield than that by the conventional heating method. F-MIL-53-AXs with iodide anion exhibited the best catalytic activity irrespective of the alkyl chain length, in agreement with the generally accepting order of nucleophilicity, ClMIL-53-AX catalysts were found to exhibit high thermal stability and were reusable over than three times, without any significant lowering of activity.

  12. Programming MIL-101Cr for selective and enhanced CO2 adsorption at low pressure by postsynthetic amine functionalization.

    Khutia, Anupam; Janiak, Christoph

    2014-01-21

    MIL-101Cr fully or partially (p) postsynthetically modified with nitro (-NO2) or amino (-NH2) groups was shown to be a robust, water stable, selective and enhanced carbon dioxide (CO2) adsorption material with the amine-functionality. The highly microporous amine-modified frameworks (up to 1.6 cm(3) g(-1) total pore volume) exhibit excellent thermal stability (>300 °C) with BET surface areas up to 2680 m(2) g(-1). At 1 bar (at 273 K) the gases CO2, CH4 and N2 are adsorbed up to 22.2 wt%, 1.67 wt% and 2.27 wt%, respectively. The two amine-modified MIL-101Cr-NH2 (4) and MIL-101Cr-pNH2 (5) showed the highest gas uptake capacities in the series with high ratios for the CO2 : N2 and CO2 : CH4 selectivities (up to 119 : 1 and 75 : 1, respectively, at 273 K). Comparison with non-modified MIL-101Cr traces the favorable CO2 adsorption properties of MIL-101Cr-NH2 (4) and MIL-101Cr-pNH2 (5) to the presence of the Lewis-basic amine groups. MIL-101Cr-NH2 (4) has a high isosteric heat of adsorption of 43 kJ mol(-1) at zero surface coverage and also >23 kJ mol(-1) over the entire adsorption range, which is well above the heat of liquefaction of bulk CO2. Large CO2 uptake capacities of amine-functionalized 4 and 5, coupled with high adsorption enthalpy, high selectivities and proven long-term water stability, make them suitable candidates for capturing CO2 at low pressure from gas mixtures including the use as a CO2 sorbent from moist air.

  13. Aging method for electronic components and systems based on MIL-HDBK 217

    Declercq, M.; Simoens, F.

    1984-01-01

    Accelerated aging tests as requested to comply IEEE Std 323-1974, rise the question of the availability of an adequate aging model. After getting through the usual models, the authors describe an aging methodology based on MIL-HDBK 217. The method, taking into account several stress factors, is shown to yield on acceptable acceleration of time, while reducing the relative importance of temperature. Practical implementation of acceleration testing is discussed, and a summary of the gained experience is made and discussed in the scope of the philosophy of IEEE Std 650. Only natural thermal aging and functional aging, excluding irradiation or thermal shocks, are considered [fr

  14. Diagnostic des systèmes de culture à base de mil [ Pennisetum ...

    Objectif : Le présent travail a pour objectif, de faire un état des lieux des systèmes de production à base de mil en Côte d'Ivoire septentrionale afin de proposer de nouvelles pistes d'amélioration. Méthodologie et résultats : L'approche méthodologique s'est reposée sur une enquête auprès des paysans sur le terrain dans ...

  15. Augmentation de la production de petits mils en Asie du Sud | CRDI ...

    La production de petits mils, en dépit des vertus nutritionnelles de cette céréale, de sa capacité de croître dans des conditions difficiles et de sa facilité de stockage, a toujours été négligée par les politiques agricoles déployées en Asie du Sud. Ces dernières, en effet, ont privilégié les cultures de rente et les céréales comme ...

  16. Novel thymine-functionalized MIL-101 prepared by post-synthesis and enhanced removal of Hg{sup 2+} from water

    Luo, Xubiao, E-mail: luoxubiao@126.com [Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang 330063 (China); College of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063 (China); Shen, Tingting; Ding, Lin; Zhong, Weiping; Luo, Jianfeng [Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang 330063 (China); College of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063 (China); Luo, Shenglian, E-mail: sllou@hnu.edu.cn [Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang 330063 (China); College of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang 330063 (China)

    2016-04-05

    Highlights: • A novel thymine-functionalized MIL-101 (MIL-101-Thymine) was first synthesized by post-synthesis method. • The resulting MIL-101-Thymine exhibited high Hg{sup 2+} adsorption. • MIL-101-Thymine exhibited excellent selectivity towards Hg{sup 2+} over other metal ions. • MIL-101-Thymine was used to remove trace Hg{sup 2+} with satisfactory recoveries in real water samples. - Abstract: A novel thymine-functionalized MIL-101 (MIL-101-Thymine) material was synthesized using a post-synthesis method to remove mercury at a high efficiency. MIL-101-Thymine was successfully prepared in this work and was confirmed by several characterization methods, such as {sup 13}C nuclear magnetic resonance, X-ray diffraction, and infrared spectroscopy. The Hg{sup 2+} adsorption agreed well with the Langmuir model, and the maximum adsorption capacity was 51.27 mg/g. The adsorption rate fit with the pseudo-second-order kinetic model. Furthermore, MIL-101-Thymine exhibited excellent selectivity towards Hg{sup 2+} over other cations, and the maximum value of the selective coefficient reached 947.34; this result is very likely due to the highly selective interactions of T-Hg{sup 2+}–T in MIL-101-Thymine. The result of X-ray photoelectron spectroscopy also showed that Hg{sup 2+} was coordinated with the N of thymine in MIL-101-Thymine. Moreover, the results of the thermogravimetric analysis and adsorption experiments showed that the Hg atom was two-coordinated with the thymine group. MIL-101-Thymine was used to remove trace Hg{sup 2+} in real water samples, and satisfactory recoveries were obtained.

  17. A Preliminary Report on the Strength and Metallography of a Bimetallic Friction Stir Weld Joint Between AA6061 and MIL-DTL-46100E High Hardness Steel Armor

    2012-11-26

    bimetallic friction stir weld joint between AA6061 and MIL-DTL-46100E High Hardness steel armor. ABSTRACT One half inch thick plates of 6061-T6 aluminum...alloy and High Hardness steel armor (MIL- STD-46100) were successfully joined by the friction stir welding (FSW) process using a tungsten-rhenium...4. TITLE AND SUBTITLE A preliminary report on the strength and metallography of a bimetallic friction stir weld joint between AA6061 and MIL-DTL

  18. Post-synthetic modification of MIL-101(Cr) with pyridine for high-performance liquid chromatographic separation of tocopherols.

    Yang, Fang; Yang, Cheng-Xiong; Yan, Xiu-Ping

    2015-05-01

    Effective separation of tocopherols is challenging and significant due to their structural similarity and important biological role. Here we report the post-synthetic modification of metal-organic framework (MOF) MIL-101(Cr) with pyridine for high-performance liquid chromatographic (HPLC) separation of tocopherols. Baseline separation of four tocopherols was achieved on a pyridine-grafted MIL-101(Cr) packed column within 10 min using hexane/isopropanol (96:4, v/v) as the mobile phase at a flow rate of 0.5 mL min(-1). The pyridine-grafted MIL-101(Cr) packed column gave high column efficiency (85,000 plates m(-1) for δ-tocopherol) and good precision (0.2-0.3% for retention time, 1.8-3.4% for peak area, 2.6-2.7% for peak height), and also offered much better performance than unmodified MIL-101(Cr) and commercial amino-bonded silica packed column for HPLC separation of tocopherols. The results not only show the promising application of pyridine-grafted MIL-101(Cr) as a novel stationary phase for HPLC separation of tocopherols, but also reveal a facile post-modification of MOFs to expand the application of MOFs in separation sciences. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. MIL-100-Fe derived N-doped Fe/Fe3C@C electrocatalysts for efficient oxygen reduction reaction

    Guo, Dakai; Han, Sancan; Wang, Jiacheng; Zhu, Yufang

    2018-03-01

    N-doped porous Fe/Fe3C@C electrocatalysts were prepared by the pyrolysis of the hexamethylenetetramine (HMT)-incorporated MIL-100-Fe at different temperatures (700-1000 °C) under N2 atmosphere. Rotary evaporation of MIL-100-Fe and HMT solution could make more N-enriched HMT molecules enter into the pores of MIL-100-Fe, thus improving nitrogen contents of the final pyrolyzed samples. All pyrolyzed samples show porous textures with middle specific surface areas. The X-ray photoelectron spectroscopy (XPS) results demonstrate the successful introduction of N atoms into carbon framework. Sample Fe-N2-800 prepared by annealing the precursors with the HMT/MIL-100-Fe weight ratio of 2 at 800 °C exhibits the best electrocatalytic activity towards the oxygen reduction reaction (ORR) in terms of onset potential and current density because of high graphitic N and pyridinic N content. The enwrapped Fe/Fe3C nanoparticles and Fe-Nx active sites in these samples could also boost the ORR activity synergistically. Moreover, sample Fe-N2-800 demonstrates a dominant four electron reduction process, as well as excellent long-term operation stability and methanol crossover resistance. Thus, the N-doped Fe/Fe3C@C composites derived from the HMT-incorporated MIL-100-Fe are promising electrocatalysts to replace Pt/C for ORR in practical applications.

  20. Evaluating the Implementation of the Re-Engineering Systems of Primary Care Treatment in the Military (RESPECT-Mil)

    Wong, Eunice C.; Jaycox, Lisa H.; Ayer, Lynsay; Batka, Caroline; Harris, Racine; Naftel, Scott; Paddock, Susan M.

    2015-01-01

    Abstract A RAND team conducted an independent implementation evaluation of the Re-Engineering Systems of Primary Care Treatment in the Military (RESPECT-Mil) Program, a system of care designed to screen, assess, and treat posttraumatic stress disorder and depression among active duty service members in the Army's primary care settings. Evaluating the Implementation of the Re-Engineering Systems of Primary Care Treatment in the Military (RESPECT-Mil) presents the results from RAND's assessment of the implementation of RESPECT-Mil in military treatment facilities and makes recommendations to improve the delivery of mental health care in these settings. Analyses were based on existing program data used to monitor fidelity to RESPECT-Mil across the Army's primary care clinics, as well as discussions with key stakeholders. During the time of the evaluation, efforts were under way to implement the Patient Centered Medical Home, and uncertainties remained about the implications for the RESPECT-Mil program. Consideration of this transition was made in designing the evaluation and applying its findings more broadly to the implementation of collaborative care within military primary care settings. PMID:28083389

  1. Représentations de niveau intermédiaire pour la modélisation d'objets

    Tsogkas , Stavros

    2016-01-01

    In this thesis we propose the use of mid-level representations, and in particular i) medial axes, ii) object parts, and iii)convolutional features, for modelling objects.The first part of the thesis deals with detecting medial axes in natural RGB images. We adopt a learning approach, utilizing colour, texture and spectral clustering features, to build a classifier that produces a dense probability map for symmetry. Multiple Instance Learning (MIL) allows us to treat scale and orientation as l...

  2. Au3+/Au0 Supported on Chromium(III Terephthalate Metal Organic Framework (MIL-101 as an Efficient Heterogeneous Catalystfor Three-Component Coupling Synthesis of Propargylamines

    Lili Liu

    2017-01-01

    Full Text Available Post-synthesis modification is a useful method for the functionalization of metal–organic frameworks (MOFs. A novel catalyst Au@MIL-101-ED-SA (ED = ethylenediamine, SA = salicylaldehyde, containing coexisting Au3+ ions and Au0 nanoparticles, was prepared successfully by post-synthesis modification with ethylenediamine, salicylaldehyde and gold. Gold nanoparticles supported on MIL-101 (Au@MIL-101 were prepared successfully by the impregnation method. Au@MIL-101-ED-SA and Au@MIL-101 were characterized by N2 adsorption–desorption, X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, and inductively coupled plasma-optical emission spectrometry. Au@MIL-101-ED-SA and Au@MIL-101 were applied as environmentally friendly catalysts in the three-component coupling reaction of aldehydes, amines, and alkynes for the preparation of diverse propargylamines. Au@MIL-101-ED-SA contained a fraction of cationic gold (Au3+/Au0 = 0.9 and showed higher catalytic activity than Au@MIL-101, which was prepared by the impregnation method. Furthermore, the reactions were performed under heterogeneous conditions and the novel catalyst was successfully recycled for four consecutive runs.

  3. Ru Nanoparticles Supported on MIL-101 by Double Solvents Method as High-Performance Catalysts for Catalytic Hydrolysis of Ammonia Borane

    Tong Liu

    2015-01-01

    Full Text Available Highly dispersed crystalline Ru nanoparticles (NPs were successfully immobilized inside the pores of MIL-101 by a double solvents method (DSM. HRTEM clearly demonstrated the uniform distribution of the ultrafine Ru NPs throughout the interior cavities of MIL-101. The synthesized Ru@MIL-101 catalyst was also characterized by X-ray diffraction (XRD, N2 adsorption desorption, and ICP-AES. The catalytic test indicated that the Ru NPs supported MIL-101 material exhibited exceedingly high activity and excellent durability for hydrogen generation from the catalytic hydrolysis of amine boranes.

  4. Characterization of adsorbed water in MIL-53(Al) by FTIR spectroscopy and ab-initio calculations.

    Salazar, J M; Weber, G; Simon, J M; Bezverkhyy, I; Bellat, J P

    2015-03-28

    Here, we report ab-initio calculations developed with a twofold purpose: understand how adsorbed water molecules alter the infrared spectrum of the metal-organic framework MIL-53(Al) and to investigate which are the associated physico-chemical processes. The analyzed structures are the two anhydrous narrow (np⊘) and large (lp⊘) pore forms and the hydrated narrow pore form (np-H2O) of the MIL-53(Al). For these structures, we determined their corresponding infrared spectra (FTIR) and we identified the vibrational modes associated to the dominant spectral lines. We show that wagging and scissoring modes of CO2 give flexibility to the structure for facilitating the lp⊘- np⊘ transition. In our studies, this transition is identified by eight vibrational modes including the δCH(18a) vibrational mode currently used to identify the mentioned transition. We report an exhaustive band identification of the infrared spectra associated to the analyzed structures. Moreover, the FTIR for the np-H2O structure allowed us to identify four types of water molecules linked to the host structure by one to three hydrogen bonds.

  5. Thermally driven refrigeration by methanol adsorption on coatings of HKUST-1 and MIL-101(Cr)

    Kummer, Harry; Baumgartner, Max; Hügenell, Philipp; Fröhlich, Dominik; Henninger, Stefan K.; Gläser, Roger

    2017-01-01

    Highlights: • A novel approach of shaping MOFs as coatings on Al-substrates used as HX materials. • The efficiency of HKUST-1 and MIL-101(Cr) for refrigeration via Methanol sorption. • The thermal stability of the MOF coatings under application relevant conditions. • Focus on early implementation by use of commercially and pre-industrially MOFs. • Modelling of sorption uptakes under application conditions for apparatus design. - Abstract: A new and versatile binder-based metal organic framework-(MOF-) coating enables efficient use in fast-cycle adsorption chillers for cooling and refrigeration applications. Two different adsorbents were presented, HKUST-1 and Mil-101(Cr), with promising methanol adsorption characteristics and high loading capacities up to 1.22 g g"−"1. Polysiloxane-based coatings containing 65 and 80 wt% of the MOF adsorbents were produced and the adsorption characteristics were studied before and after extensive thermal treatment over 1000 cycles between 20 °C and 130 °C under methanol atmosphere by thermogravimetric analysis and X-ray diffractometry. Using the Dubinin-Astakhov approach, possible methanol loading lifts in a refrigeration process under different application conditions were quantified.

  6. MIL-100 derived nitrogen-embodied carbon shells embedded with iron nanoparticles

    Mao, Chengyu; Kong, Aiguo; Wang, Yuan; Bu, Xianhui; Feng, Pingyun

    2015-06-01

    The use of metal-organic frameworks (MOFs) as templates and precursors to synthesize new carbon materials with controllable morphology and pre-selected heteroatom doping holds promise for applications as efficient non-precious metal catalysts. Here, we report a facile pyrolysis pathway to convert MIL-100 into nitrogen-doped carbon shells encapsulating Fe nanoparticles in a comparative study involving multiple selected nitrogen sources. The hierarchical porous architecture, embedded Fe nanoparticles, and nitrogen decoration endow this composite with a superior oxygen reduction activity. Furthermore, the excellent durability and high methanol tolerance even outperform the commercial Pt-C catalyst.The use of metal-organic frameworks (MOFs) as templates and precursors to synthesize new carbon materials with controllable morphology and pre-selected heteroatom doping holds promise for applications as efficient non-precious metal catalysts. Here, we report a facile pyrolysis pathway to convert MIL-100 into nitrogen-doped carbon shells encapsulating Fe nanoparticles in a comparative study involving multiple selected nitrogen sources. The hierarchical porous architecture, embedded Fe nanoparticles, and nitrogen decoration endow this composite with a superior oxygen reduction activity. Furthermore, the excellent durability and high methanol tolerance even outperform the commercial Pt-C catalyst. Electronic supplementary information (ESI) available: Material synthesis and elemental analysis, electrochemistry measurements, and additional figures. See DOI: 10.1039/c5nr02346g

  7. The MIL-88A-Derived Fe3O4-Carbon Hierarchical Nanocomposites for Electrochemical Sensing

    Wang, Li; Zhang, Yayun; Li, Xia; Xie, Yingzhen; He, Juan; Yu, Jie; Song, Yonghai

    2015-01-01

    Metal or metal oxides/carbon nanocomposites with hierarchical superstructures have become one of the most promising functional materials in sensor, catalysis, energy conversion, etc. In this work, novel hierarchical Fe3O4/carbon superstructures have been fabricated based on metal-organic frameworks (MOFs)-derived method. Three kinds of Fe-MOFs (MIL-88A) with different morphologies were prepared beforehand as templates, and then pyrolyzed to fabricate the corresponding novel hierarchical Fe3O4/carbon superstructures. The systematic studies on the thermal decomposition process of the three kinds of MIL-88A and the effect of template morphology on the products were carried out in detail. Scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy and thermal analysis were employed to investigate the hierarchical Fe3O4/carbon superstructures. Based on these resulted hierarchical Fe3O4/carbon superstructures, a novel and sensitive nonenzymatic N-acetyl cysteine sensor was developed. The porous and hierarchical superstructures and large surface area of the as-formed Fe3O4/carbon superstructures eventually contributed to the good electrocatalytic activity of the prepared sensor towards the oxidation of N-acetyl cysteine. The proposed preparation method of the hierarchical Fe3O4/carbon superstructures is simple, efficient, cheap and easy to mass production. It might open up a new way for hierarchical superstructures preparation. PMID:26387535

  8. CuNi NPs supported on MIL-101 as highly active catalysts for the hydrolysis of ammonia borane

    Gao, Doudou; Zhang, Yuhong; Zhou, Liqun; Yang, Kunzhou

    2018-01-01

    The catalysts containing Cu, Ni bi-metallic nanoparticles were successfully synthesized by in-situ reduction of Cu2+ and Ni2+ salts into the highly porous and hydrothermally stable metal-organic framework MIL-101 via a simple liquid impregnation method. When the total amount of loading metal is 3 × 10-4 mol, Cu2Ni1@MIL-101 catalyst shows higher catalytic activity comparing to CuxNiy@MIL-101 with different molar ratio of Cu and Ni (x, y = 0, 0.5, 1.5, 2, 2.5, 3). Cu2Ni1@MIL-101 catalyst has the highest catalytic activity comparing to mono-metallic Cu and Ni counterparts and pure bi-metallic CuNi nanoparticles in hydrolytic dehydrogeneration of ammonia borane (AB) at room temperature. Additionally, in the hydrolysis reaction, the Cu2Ni1@MIL- 101 catalyst possesses excellent catalytic performances, which exhibit highly catalytic activity with turn over frequency (TOF) value of 20.9 mol H2 min-1 Cu mol-1 and a very low activation energy value of 32.2 kJ mol-1. The excellent catalytic activity has been successfully achieved thanks to the strong bi-metallic synergistic effects, uniform distribution of nanoparticles and the bi-functional effects between CuNi nanoparticles and the host of MIL-101. Moreover, the catalyst also displays satisfied durable stability after five cycles for the hydrolytically releasing H2 from AB. The non-noble metal catalysts have broad prospects for commercial applications in the field of hydrogen-stored materials due to the low prices and excellent catalytic activity.

  9. Post synthetic modification of MIL-101(Cr) for S-shaped isotherms and fast kinetics with water adsorption

    Teo, How Wei Benjamin; Chakraborty, Anutosh; Kayal, Sibnath

    2017-01-01

    Highlights: • Modification of parent MIL-101(Cr) metal organic framework (MOF) employing alkali metal ions (Li + , Na + , K + ). • Surface characteristics of the parent and alkali doped MIL-101(Cr) adsorbents. • Water uptakes are measured for the temperatures ranging from 25 °C to 60 °C under static and dynamic conditions. • Isotherms and kinetics data are fitted with Langmuir analogy models. • The 5% Li-doped MIL-101(Cr) is suitable for adsorption cooling. - Abstract: This article presents the surface characteristics of alkali (Li + , Na + , K + ) doped MIL-101(Cr) metal organic frameworks (MOFs), and the structural properties are evaluated by scanning electron micrography (SEM), X-ray diffraction (XRD), thermo-gravimetric analyser (TGA) and N 2 adsorption analysis. The amount of water uptakes are measured by a gravimetric analyser for the temperatures ranging from 298 K to 333 K and pressures up to the saturated conditions. The experimentally measured isotherms and kinetics data are fitted with the equations developed from the concept of Langmuir analogy. The isosteric heat of adsorption is calculated employing Van’t Hoff equation in the pressure-temperature-uptake co-ordinate systems. The hydrophobic length at low pressure regions is shortened by the addition of alkali dopants. It is observed that the alkali (Na, K and Li) ions on MIL-101(Cr) MOF increase the water uptakes at lower relative pressure region with fast kinetics. We have shown here that the alkali doped MIL-101(Cr) MOFs can be used as potential adsorbents for various low temperature heat transmission applications such as adsorption assisted heat pump, cooling and desalination.

  10. Mineralogy and Petrography of MIL 090001, a Highly Altered CV Chondrite from the Reduced Sub-Group

    Keller, Lindsay P.

    2011-01-01

    MIL 090001 is a large (greater than 6 kg) CV chondrite from the reduced subgroup (CV(sub red)) that was recovered during the 2009-2010 ANSMET field season [1]. The CV(sub red) subgroup meteorites retain primitive characteristics and have escaped the Na and Fe meta-somatism that affected the oxidized (CV(sub ox)) subgroups. MIL 090001 is, however, reported to be altered [1], and thus a major objective of this study is to characterize its mineralogy and petrography and the extent of the alteration.

  11. Juegos de palabras y música en El Cortesano de Luis Milán

    Alfonso Colella

    2015-12-01

    Full Text Available Este artículo analiza cómo, en El Cortesano, la música y la actuación musical se ven fuertemente afectadas por el carácter burlesco e ingenioso de todos los personajes que frecuentan las reuniones de Fernando de Aragón y de la reina Germana de Foix. Por lo tanto, el músico Milán, para cumplir con todas las expectativas de este mundo del entretenimiento y del juego, debe basarse necesariamente en una serie de opciones interpretativas que permitan actuaciones rápidas en función de las demandas de su público. Lo que emerge es una imagen del músico y de la música diferente de lo que se esperaría normalmente. En una sociedad de este tipo, no cuenta la música entendida en su estética y aspectos técnicos, sino la capacidad de gestionar las apariencias y someterse a las pruebas y los mandatos impuestos por los rituales del juego cortesano. Tenemos muchos ejemplos en que Milán se muestra con pasividad y sumisión. Pero es normal, porque esto entra en los códigos de la vida de la corte. This article takes into consideration El Cortesano (1561 by Luis Milán: in this text the musical performance is strongly influenced by the playful attitudes of the individuals who attended the court meetings of Fernando de Aragón and Germana de Foix. Therefore, the musician has to keep in mind every expectation of courtly entertainment and gaming, and morevoer he must open his interpretative options to meet also the demands of the public. What emerges is a picture of the musician and his music that is different from what one would expect in another social context. In such aristocratic society as the Duke of Calabria, music was not understood only in terms of its aesthetic values and technical aspects, but it also required that the player accepted the rituals of the courtly game.

  12. Feria de Milán. Pabellón de maquinaria pesada

    Covre, Gino

    1960-04-01

    Full Text Available Después de demoler el edificio destinado a las exposiciones de los adelantos y mejoras de la mecánica pesada, las autoridades Que rigen estas manifestaciones de la mecánica en Milán, Italia, se entregaron a un estudio de conjunto del problema que para ellos constituía la construcción de un pabellón que sustituyera al destruido y que, tanto por sus condiciones intrínsecas como por su aspecto estático y funcional, supliera ampliamente a su antecesor. El solar disponible constituía una amplia parcela aislada, y se pensó, en principio, en un cuerpo arquitectónico de dos plantas, una en semisótano y otra superior que constituiría la sala general de las exposiciones.

  13. MIL-STD-1553 dynamic bus controller/remote terminal hybrid set

    Friedman, S. N.

    This paper describes the performance, physical and electrical requirements of a Dual Redundant BUS Interface Unit (BIU) acting as a BUS Controller Interface Unit (BCIU) or Remote Terminal Unit (RTU) between a Motorola 68000 VME BUS and MIL-STD-1553B Multiplex Data Bus. A discussion of how the BIU Hybrid set is programmed, and operates as a BCIU or RTU, will be included. This paper will review Dynamic Bus Control and other Mode Code capabilities. The BIU Hybrid Set interfaces to a 68000 Microprocessor with a VME Bus using programmed I/O transfers. This special interface will be discussed along with the internal Dual Access Memory (4K x 16) used to support the data exchanges between the CPU and the BIU Hybrid Set. The hybrid set's physical size and power requirements will be covered. This includes the present Double Eurocard the BIU function is presently being offered on.

  14. Sparse Representation Based Multi-Instance Learning for Breast Ultrasound Image Classification.

    Bing, Lu; Wang, Wei

    2017-01-01

    We propose a novel method based on sparse representation for breast ultrasound image classification under the framework of multi-instance learning (MIL). After image enhancement and segmentation, concentric circle is used to extract the global and local features for improving the accuracy in diagnosis and prediction. The classification problem of ultrasound image is converted to sparse representation based MIL problem. Each instance of a bag is represented as a sparse linear combination of all basis vectors in the dictionary, and then the bag is represented by one feature vector which is obtained via sparse representations of all instances within the bag. The sparse and MIL problem is further converted to a conventional learning problem that is solved by relevance vector machine (RVM). Results of single classifiers are combined to be used for classification. Experimental results on the breast cancer datasets demonstrate the superiority of the proposed method in terms of classification accuracy as compared with state-of-the-art MIL methods.

  15. Fabrication of core-shell MIL-101(Cr)@UiO-66(Zr) nanocrystals for hydrogen storage

    Ren, Jianwei

    2014-09-01

    Full Text Available of the individual metal-organic framework (MOF) components and the coreeshell hybrid crystals were also characterized. The hydrogen storage capacity exhibited by the resulting core eshell nanocrystals was 26% and 60% higher than those of pure phase MIL-101 and Ui...

  16. Interfacing the septa movement (DC motors) equipment to the PS control system and the MIL1553 bus

    Dehavay, Claude

    1995-01-01

    Continuing the rejuvenation of the PS Control system , this application replaces the Single Transceiver Hybrid used to interface the Septa Movement Fquipment by a G64 system connected to the VME crate via the MIL1553 bus. This note explains the G64 hardware interface and details the standard message as defined in the Control Protocole for Power Converter, RF and Stepping Motor equipment.

  17. Towards protective MOFs: post-synthetic modification of MIL-101 with oxime groups and their interactions with toxic chemicals

    Grol, M. van; Gorzkowska-Sobasb, A.A.; Koning, M.C. de

    2017-01-01

    In an attempt to broaden the scope of protective MOFs towards toxic compounds, we decided to introduce a reactive (nucleophilic) functionality in MIL101 by post-synthesis modification 1,2. This functionality would complement already existing adsorptive properties with an ability to capture or

  18. Effets de la microdose sur la production du niébé, du mil et du ...

    respectivement pour le sorgho, le mil et le niébé comparativement au témoin. La microdose a été .... Les prix utilisés sont celui du marché local au moment des semis pour les engrais soit 17500 FCFA pour NPK et ..... Projet « Transfert de la.

  19. Selective recognition of 6-mercaptopurine based on luminescent metal-organic frameworks Fe-MIL-88NH₂.

    Sun, Zhengjuan; Liu, Yali; Li, Yuanfang

    2015-03-15

    A novel and rapid spectrofluorometry method for the recognition of 6-mercaptopurine (6-MP) has been developed based on luminescent metal-organic frameworks Fe-MIL-88NH2 as fluorescent probe. The strong fluorescence of Fe-MIL-88NH2 at 430 nm could be quenched by 6-MP directly, and the Fe-MIL-88NH2 shows high selectivity for 6-MP compared to other thiol-containing amino acids such as homocysteine (Hcy), cysteine (Cys), glutathione (GSH), etc. Under optimal conditions, the relative fluorescence intensity was linearly proportional to the concentration of 6-MP in the range of 5-600 μM with the detection limit at 1.17 μM (S/N=3). Furthermore, the present approach has been successfully applied to the determination of 6-MP in human serum samples. The possible fluorescence quenching mechanism has also been investigated, where it is revealed that the quenching was attributed to competition of absorption of the light source energy as well as electron transfer between Fe-MIL-88NH2 and 6-MP. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Multiple Nebular Gas Reservoirs Recorded by Oxygen Isotope Variation in a Spinel-Rich CAI in CO3 MIL 090019

    Simon, J. I.; Simon, S. B.; Nguyen, A. N.; Ross, D. K.; Messenger, S.

    2017-07-01

    We conducted NanoSIMS ion imaging studies of a primitive spinel-rich CAI from the MIL 090019 CO3 chondrite. It records radial O-isotopic heterogeneity among multiple occurrences of the same mineral, reflecting distinct nebular O-isotopic reservoirs.

  1. Effets de la microdose sur la production du niébé, du mil et du ...

    Effets de la microdose sur la production du niébé, du mil et du sorgho en fonction la toposéquence. Fatimata Saba, Sibiri Jean Baptiste Taonda, Idriss Serme, Alimata A. Bandaogo, Augustin P. Sourwema, Adama Kabre ...

  2. Developing student engagement in networked teaching and learning practices through problem- and project-based learning approaches

    Andreasen, Lars Birch; Lerche Nielsen, Jørgen

    2012-01-01

    This paper focuses on how learner engagement can be facilitated through use of social media and communication technologies. The discussions are based on the Danish Master’s Programme of ICT and Learning (MIL), where students study in groups within a networked learning structure. The paper reflect...

  3. Fluorescent metal-organic framework MIL-53(Al) for highly selective and sensitive detection of Fe3+ in aqueous solution.

    Yang, Cheng-Xiong; Ren, Hu-Bo; Yan, Xiu-Ping

    2013-08-06

    Fluorescent metal-organic frameworks (MOFs) have received great attention in sensing application. Here, we report the exploration of fluorescent MIL-53(Al) for highly selective and sensitive detection of Fe(3+) in aqueous solution. The cation exchange between Fe(3+) and the framework metal ion Al(3+) in MIL-53(Al) led to the quenching of the fluorescence of MIL-53(Al) due to the transformation of strong-fluorescent MIL-53(Al) to weak-fluorescent MIL-53(Fe), allowing highly selective and sensitive detection of Fe(3+) in aqueous solution with a linear range of 3-200 μM and a detection limit of 0.9 μM. No interferences from 0.8 M Na(+); 0.35 M K(+); 11 mM Cu(2+); 10 mM Ni(2+); 6 mM Ca(2+), Pb(2+), and Al(3+); 5.5 mM Mn(2+); 5 mM Co(2+) and Cr(3+); 4 mM Hg(2+), Cd(2+), Zn(2+), and Mg(2+); 3 mM Fe(2+); 0.8 M Cl(-); 60 mM NO2(-) and NO3(-); 10 mM HPO4(2-), H2PO4(-), SO3(2-), SO4(2-), and HCOO(-); 8 mM CO3(2-), HCO3(-), and C2O4(2-); and 5 mM CH3COO(-) were found for the detection of 150 μM Fe(3+). The possible mechanism for the quenching effect of Fe(3+) on the fluorescence of MIL-53(Al) was elucidated by inductively coupled plasma-mass spectrometry, X-ray diffraction spectrometry, and Fourier transform infrared spectrometry. The specific cation exchange behavior between Fe(3+) and the framework Al(3+) along with the excellent stability of MIL-53(Al) allows highly selective and sensitive detection of Fe(3+) in aqueous solution. The developed method was applied to the determination of Fe(3+) in human urine samples with the quantitative spike recoveries from 98.2% to 106.2%.

  4. MIL-Ti metal-organic frameworks (MOFs) nanomaterials as superior adsorbents: Synthesis and ultrasound-aided dye adsorption from multicomponent wastewater systems.

    Oveisi, Mina; Asli, Mokhtar Alina; Mahmoodi, Niyaz Mohammad

    2018-04-05

    Herein, 1,4-benzenedicarboxylate (BDC) and 2-amino-1,4-benzenedicarboxylate (NH 2 -BDC) as organic linkers and tetraisopropyl orthotitanate as a metal source were used to synthesize several metal-organic frameworks (MOFs) nanomaterials. Five Materials Institut Lavoisiers (MILs) as MOFs include MIL-125(Ti), NH 2 -MIL-125(Ti) and three MILs with different organic linkers molar ratios (BDC/NH 2 -BDC: 75/25, 50/50 and 25/75 denoted as MIL-X1, MIL-X2 and MIL-X3, respectively). The synthesized nanomaterials were used for ultrasound-aided adsorption of cationic dyes (Basic Red 46 (BR46), Basic Blue 41 (BB41) and Methylene Blue (MB)) from single and multicomponent (binary) systems. The BET, XRD, FTIR, SEM, TEM, TGA and zeta potential were used for characterizing the MILs. Dye removal followed pseudo-second order kinetics with constant rate of 0.20833, 0.00481 and 0.00051 mg/g min for BR46, BB41 and MB, respectively. In addition dye adsorption obeyed the Langmuir isotherm model and the experimental dye adsorption capacity for BR46, BB41 and MB was 1296, 1257 and 862 mg/g, respectively. The synthesized MIL showed high reusability and stability over three cycles. The adsorption thermodynamics data presented that dye removal was a spontaneous, endothermic and physical reaction. The free Gibbs energy for dye removal by the NH 2 -MIL-125(Ti) at 308K was -19.424, -15.721 and -17.413 kJ/mol for BR46, BB41 and MB, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Ship-in-a-bottle CMPO in MIL-101(Cr) for selective uranium recovery from aqueous streams through adsorption

    De Decker, Jeroen [Department of Inorganic and Physical Chemistry, Center for Ordered Materials, Organometallics, and Catalysis (COMOC), Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium); Folens, Karel [Laboratory of Analytical Chemistry and Applied Ecochemistry, Ghent University, Coupure Links 653, 9000 Ghent (Belgium); De Clercq, Jeriffa [Department of Materials, Textiles, and Chemical Engineering, Industrial Catalysis and Adsorption Technology (INCAT), Ghent University, Valentin, Vaerwyckweg 1, 9000 Ghent (Belgium); Meledina, Maria; Van Tendeloo, Gustaaf [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Du Laing, Gijs [Laboratory of Analytical Chemistry and Applied Ecochemistry, Ghent University, Coupure Links 653, 9000 Ghent (Belgium); Van Der Voort, Pascal, E-mail: pascal.vandervoort@ugent.be [Department of Inorganic and Physical Chemistry, Center for Ordered Materials, Organometallics, and Catalysis (COMOC), Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium)

    2017-08-05

    Highlights: • Highly stable metal-organic framework, MIL-101(Cr), for uses in aqueous, acidic adsorption. • Uranium recovery from low concentration acidic solutions. • One-step ship-around-the-bottle synthetic approach to incorporate CMPO in MIL-101(Cr). • Highly selective U(VI) adsorbent in competition with a high variety of metals, incl. rare earths and transition metals. • Regenerable and reusable adsorbent via 0.1 M nitric acid stripping. - Abstract: Mesoporous MIL-101(Cr) is used as host for a ship-in-a-bottle type adsorbent for selective U(VI) recovery from aqueous environments. The acid-resistant cage-type MOF is built in-situ around N,N-Diisobutyl-2-(octylphenylphosphoryl)acetamide (CMPO), a sterically demanding ligand with high U(VI) affinity. This one-step procedure yields an adsorbent which is an ideal compromise between homogeneous and heterogeneous systems, where the ligand can act freely within the pores of MIL-101, without leaching, while the adsorbent is easy separable and reusable. The adsorbent was characterized by XRD, FTIR spectroscopy, nitrogen adsorption, XRF, ADF-STEM and EDX, to confirm and quantify the successful encapsulation of the CMPO in MIL-101, and the preservation of the host. Adsorption experiments with a central focus on U(VI) recovery were performed. Very high selectivity for U(VI) was observed, while competitive metal adsorption (rare earths, transition metals...) was almost negligible. The adsorption capacity was calculated at 5.32 mg U/g (pH 3) and 27.99 mg U/g (pH 4), by fitting equilibrium data to the Langmuir model. Adsorption kinetics correlated to the pseudo-second-order model, where more than 95% of maximum uptake is achieved within 375 min. The adsorbed U(VI) is easily recovered by desorption in 0.1 M HNO{sub 3}. Three adsorption/desorption cycles were performed.

  6. Fabrication Parameters of Asymmetric Mixed Matrix Matrimid-MIL-53/PMHS Membrane for CO2/CH4 Separation

    Fatereh Dorosti

    2017-03-01

    Full Text Available Asymmetrically mixed matrix Matrimid-MIL-53 membranes with silicone cover layer were fabricated. For better understanding of membrane fabrication process, three main parameters of fabrication, Matrimid concentration, silicone concentration and weight percentage of metal organic framework (MIL-53 particles, were optimized by an experimental design method. Cross-section SEM images were used to study the membrane structure and polymer-particles interface. Moreover, thermal resistance of the membranes and the existence of various bonds in them were investigated by FTIR and TGA analyses. The results showed that membranes had porous structure with finger-like morphology. At low and moderate percentages of particles, there were no non-selective voids observed at polymer-particles interface. The thermal resistance of membranes increased with the increase of MIL-53 weight percentage and the destruction temperature of polymer increased from 410°C to 450°C. The permeability tests results showed that the Matrimid (20% wt-MIL-53(15% wt/PMHS (10%wt membrane exhibited the highest level of CO2/CH4 selectivity (23.6. However, in the membrane with 30 wt% particles loading, selectivity decreased due to particles agglomeration and void formation. The experimental design results showed that the concentration of silicone in covering solution had significant effect. CO2 and CH4 permeability decreased and ideal selectivity of CO2/CH4 increased with silicone concentration enhancement. Although the Matrimid concentration had a little effect on CO2/CH4 ideal selectivity, its enhancement increased the selectivity of the gases. The optimization results showed the membrane with 17.8% of Matrimd polymer, 13.2% of silicone polymer and 15.5 wt% of MIL-53 particle displayed the highest selectivity and CO2 permeability.

  7. Ship-in-a-bottle CMPO in MIL-101(Cr) for selective uranium recovery from aqueous streams through adsorption

    De Decker, Jeroen; Folens, Karel; De Clercq, Jeriffa; Meledina, Maria; Van Tendeloo, Gustaaf; Du Laing, Gijs; Van Der Voort, Pascal

    2017-01-01

    Highlights: • Highly stable metal-organic framework, MIL-101(Cr), for uses in aqueous, acidic adsorption. • Uranium recovery from low concentration acidic solutions. • One-step ship-around-the-bottle synthetic approach to incorporate CMPO in MIL-101(Cr). • Highly selective U(VI) adsorbent in competition with a high variety of metals, incl. rare earths and transition metals. • Regenerable and reusable adsorbent via 0.1 M nitric acid stripping. - Abstract: Mesoporous MIL-101(Cr) is used as host for a ship-in-a-bottle type adsorbent for selective U(VI) recovery from aqueous environments. The acid-resistant cage-type MOF is built in-situ around N,N-Diisobutyl-2-(octylphenylphosphoryl)acetamide (CMPO), a sterically demanding ligand with high U(VI) affinity. This one-step procedure yields an adsorbent which is an ideal compromise between homogeneous and heterogeneous systems, where the ligand can act freely within the pores of MIL-101, without leaching, while the adsorbent is easy separable and reusable. The adsorbent was characterized by XRD, FTIR spectroscopy, nitrogen adsorption, XRF, ADF-STEM and EDX, to confirm and quantify the successful encapsulation of the CMPO in MIL-101, and the preservation of the host. Adsorption experiments with a central focus on U(VI) recovery were performed. Very high selectivity for U(VI) was observed, while competitive metal adsorption (rare earths, transition metals...) was almost negligible. The adsorption capacity was calculated at 5.32 mg U/g (pH 3) and 27.99 mg U/g (pH 4), by fitting equilibrium data to the Langmuir model. Adsorption kinetics correlated to the pseudo-second-order model, where more than 95% of maximum uptake is achieved within 375 min. The adsorbed U(VI) is easily recovered by desorption in 0.1 M HNO 3 . Three adsorption/desorption cycles were performed.

  8. Dimensions of problem based learning

    Nielsen, Jørgen Lerche; Andreasen, Lars Birch

    2013-01-01

    The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning such...... and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....

  9. Multiple instances of paraphyletic species and cryptic taxa revealed by mitochondrial and nuclear RAD data for Calandrella larks (Aves: Alaudidae).

    Stervander, Martin; Alström, Per; Olsson, Urban; Ottosson, Ulf; Hansson, Bengt; Bensch, Staffan

    2016-09-01

    The avian genus Calandrella (larks) was recently suggested to be non-monophyletic, and was divided into two genera, of which Calandrella sensu stricto comprises 4-5 species in Eurasia and Africa. We analysed mitochondrial cytochrome b (cytb) and nuclear Restriction-site Associated DNA (RAD) sequences from all species, and for cytb we studied 21 of the 22 recognised subspecies, with the aim to clarify the phylogenetic relationships within the genus and to compare large-scale nuclear sequence patterns with a widely used mitochondrial marker. Cytb indicated deep splits among the currently recognised species, although it failed to support the interrelationships among most of these. It also revealed unexpected deep divergences within C. brachydactyla, C. blanfordi/C. erlangeri, C. cinerea, and C. acutirostris. It also suggested that both C. brachydactyla and C. blanfordi, as presently circumscribed, are paraphyletic. In contrast, most of the many subspecies of C. brachydactyla and C. cinerea were unsupported by cytb, although two populations of C. cinerea were found to be genetically distinct. The RAD data corroborated the cytb tree (for the smaller number of taxa analysed) and recovered strongly supported interspecific relationships. However, coalescence analyses of the RAD data, analysed in SNAPP both with and without an outgroup, received equally strong support for two conflicting topologies. We suggest that the tree rooted with an outgroup - which is not recommended for SNAPP - is more trustworthy, and suggest that the reliability of analyses performed without any outgroup species should be thoroughly evaluated. We also demonstrate that degraded museum samples can be phylogenetically informative in RAD analyses following careful bioinformatic treatment. We note that the genus Calandrella is in need of taxonomic revision. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Ni-Pt nanoparticles growing on metal organic frameworks (MIL-96) with enhanced catalytic activity for hydrogen generation from hydrazine at room temperature.

    Wen, Lan; Du, Xiaoqiong; Su, Jun; Luo, Wei; Cai, Ping; Cheng, Gongzhen

    2015-04-07

    Well-dispersed bimetallic Ni-Pt nanoparticles (NPs) with different compositions have been successfully grown on the MIL-96 by a simple liquid impregnation method using NaBH4 as the reducing agent. Powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, N2 adsorption-desorption, and inductively coupled plasma-atomic emission spectroscopy measurements were employed to characterize the NiPt/MIL-96. Catalytic activity of NiPt/MIL-96 catalysts was tested in the hydrogen generation from the aqueous alkaline solution of hydrazine at room temperature. These catalysts are composition dependent on their catalytic activity, while Ni64Pt36/MIL-96 exhibits the highest catalytic activity among all the catalysts tested, with a turnover frequency value of 114.3 h(-1) and 100% hydrogen selectivity. This excellent catalytic performance might be due to the synergistic effect of the MIL-96 support and NiPt NPs, while NiPt NPs supported on other conventional supports, such as SiO2, carbon black, γ-Al2O3, poly(N-vinyl-2-pyrrolidone) (PVP), and the physical mixture of NiPt and MIL-96, all of them exhibit inferior catalytic activity compared to that of NiPt/MIL-96.

  11. El uso del hierro en la Casa Milá de Barcelona

    Vila Rodríguez, Rafael

    1990-08-01

    Full Text Available The materials and construction systems, even the conception of the general structure, were for Gaudí no more than mediums at the service of the formal and spatial expression of his architectural imagination. Sometimes, the use of certain materials was indiscriminate or without sufficient guarantees. The Casa Milá is a good example. The use of laminated iron in the Pedrera, which allowed Gaudí to conceive a story independent of the façades —wall-screens of stone which seem to defy the law of gravity—, have been, at the same time, the main cause of the deterioration of these façades. In the case of the structure, the conceptual solution based on the use of iron has responded well to the static needs. This has not occured with the solutions —no less ingeneous but too improvlsed and risky— foreseen, also based on iron, to hold up the façade. Here, the material, subjected to the effects of humidity —favored by the form given to the stone—, has not resisted the passage of time very well.

    Los materiales y los sistemas constructivos, incluso la concepción de la estructura general, no eran para Gaudí más que medios al servicio de la expresividad formal y espacial de su imaginativa arquitectura. A veces, la utilización de algunos materiales se hizo de forma indiscriminada o sin suficientes garantías. La Casa Milá es un buen ejemplo. La utilización del hierro laminado en la Pedrera, que permitió a Gaudí concebir una planta libre independiente de las fachadas —muros-cortina de piedra que parecen desafiar la ley de la gravedad—, ha sido, al mismo tiempo, la causa principal del deterioro de estas fachadas. En el caso de la estructura, la solución conceptual basada en el uso del hierro ha respondido bien a las solicitudes estáticas. No ha ocurrido así con las soluciones —no menos ingeniosas pero excesivamente improvisadas y arriesgadas— previstas, también en base al hierro, para la sustentación de la fachada. Aqu

  12. Stable ABTS Immobilized in the MIL-100(Fe) Metal-Organic Framework as an Efficient Mediator for Laccase-Catalyzed Decolorization.

    Liu, Youxun; Geng, Yuanyuan; Yan, Mingyang; Huang, Juan

    2017-06-02

    The successful encapsulation of 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), a well-known laccase mediator, within a mesoporous metal-organic framework sample (i.e., MIL-100(Fe)) was achieved using a one-pot hydrothermal synthetic method. The as-prepared ABTS@MIL-100(Fe) was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen sorption, and cyclic voltammetry (CV). Our ABTS@MIL-100(Fe)-based electrode exhibited an excellent electrochemical response, indicating that MIL-100(Fe) provides an appropriate microenvironment for the immobilization and electroactivity of ABTS molecules. ABTS@MIL-100(Fe) was then evaluated as an immobilized laccase mediator for dye removal using indigo carmine (IC) as a model dye. Through the application of laccase in combination with a free (ABTS) or immobilized (ABTS@MIL-100(Fe)) mediator, decolorization yields of 95% and 94%, respectively, were obtained for IC after 50 min. In addition, following seven reuse cycles of ABTS@MIL-100(Fe) for dye treatment, a decolorization yield of 74% was obtained. Dye decolorization occurred through the breakdown of the chromophoric group by the Laccase/ABTS@MIL-100(Fe) system, and a catalytic mechanism was proposed. We therefore expect that the stability, reusability, and validity of ABTS@MIL-100(Fe) as a laccase mediator potentially render it a promising tool for dye removal, in addition to reducing the high running costs and potential toxicity associated with synthetic mediators.

  13. Petrology and Geochemistry of Unbrecciated Harzburgitic Diogenite MIL 07001: A Window Into Vestan Geological Evolution

    Mittlefehldt, D. W.; Peng, Z. X.; Mertzman, S. A.; Mertzman, K. R.

    2014-01-01

    There is a strong case that asteroid 4 Vesta is the parent of the howardite, eucrite and diogenite (HED) meteorites. Models developed for the geological evolution of Vesta can satisfy the compositions of basaltic eucrites that dominate in the upper crust. The bulk compositional characteristics of diogenites - cumulate harzburgites and orthopyroxenites from the lower crust - do not fit into global magma ocean models that can describe the compositions of basaltic and cumulate eucrites. Recent more detailed formation models do make provision for a more complicated origin for diogenites, but this model has yet to be completely vetted. Compositional studies of bulk samples has led to the hypothesis that many diogenites were formed late by interaction of their parent melts with a eucritic crust, but those observations may alternatively be explained by subsolidus equilibration of trace elements between orthopyroxene and plagioclase and Ca-phosphate in the rocks. Differences in radiogenic Mg-26 content between diogenites and eucrites favors early formation of the former, not later formation. Understanding the origin of diogenites is crucial for understanding the petrologic evolution of Vesta. We have been doing coordinated studies of a suite of diogenites including petrologic investigations, bulk rock major and trace element studies, and in situ trace element analyses of orthopyroxene. Here we will focus on an especially unusual, and potentially key, diogenite, MIL 07001.

  14. Modified Spectral Fatigue Methods for S-N Curves With MIL-HDBK-5J Coefficients

    Irvine, Tom; Larsen, Curtis

    2016-01-01

    The rainflow method is used for counting fatigue cycles from a stress response time history, where the fatigue cycles are stress-reversals. The rainflow method allows the application of Palmgren-Miner's rule in order to assess the fatigue life of a structure subject to complex loading. The fatigue damage may also be calculated from a stress response power spectral density (PSD) using the semi-empirical Dirlik, Single Moment, Zhao-Baker and other spectral methods. These methods effectively assume that the PSD has a corresponding time history which is stationary with a normal distribution. This paper shows how the probability density function for rainflow stress cycles can be extracted from each of the spectral methods. This extraction allows for the application of the MIL-HDBK-5J fatigue coefficients in the cumulative damage summation. A numerical example is given in this paper for the stress response of a beam undergoing random base excitation, where the excitation is applied separately by a time history and by its corresponding PSD. The fatigue calculation is performed in the time domain, as well as in the frequency domain via the modified spectral methods. The result comparison shows that the modified spectral methods give comparable results to the time domain rainflow counting method.

  15. SEDS MIL-STD-1773 fiber optic data bus: Proton irradiation test results and spaceflight SEU data

    LaBel, K.A.; Stassinopoulos, E.G.; Miller, J.T. (NASA/GSFC, Greenbelt, MD (United States)); Marshall, P. (NRL/SFA, Washington, DC (United States)); Dale, C. (NRL, Washington, DC (United States)); Crabtree, C.M. (Hughes/ST Systems Corp., Seabrook, MD (United States)); Gates, M.M. (Jackson and Tull, Seabrook, MD (United States))

    1993-12-01

    The Small Explorer Data System (SEDS) was launched in July of 1992 as part of the Solar Anomalous Magnetospheric Particle Explorer (SAMPEX) mission. The SEDS utilizes NASA's first MIL-STD-1773 Fiber Optic Multiplexed Data Bus (or 1773 bus) to communicate with other spacecraft subsystems in the space environment. The 1773 bus is the fiber optic version of the MIL-STD-1553 Data Bus, a electronic wire bus used in many avionics applications. The authors present proton test and space flight single event effect data for NASA's first fiber optic data bus. Bit error rate predictions based on a new proton direct ionization model agree well with flight data for proton belt and solar flare effects.

  16. Urea-modified metal-organic framework of type MIL-101(Cr) for the preconcentration of phosphorylated peptides

    Yang, Xiaoqing; Xia, Yan

    2016-01-01

    Mass spectrometry (MS) is the most powerful tool in phosphoproteomics research. However, phosphopeptides usually are present in low concentrations and their preconcentration therefore is highly desired. We describe a two-step method for the synthesis of a metal organic framework of the type MIL-101(Cr) that is modified with urea (then designated as MIL-101(Cr)-UR 2 ). It possesses large surface area, good solvent stability and high affinity for some phosphates. Due to the presence of modified urea functions, this material allows for selective and effective enrichment of phosphorylated peptides. It was successfully applied to the enrichment of phosphopeptides from non-fat-milk. The method was applied to the detection of phosphopeptides in a tryptic digest of β-casein where is showed a detection sensitivity as low as 10 −10 M. (author)

  17. Technology-enhanced instruction in learning world languages: The Middlebury interactive learning program

    Cynthia Lake

    2015-03-01

    Full Text Available Middlebury Interactive Language (MIL programs are designed to teach world language courses using blended and online learning for students in kindergarten through grade 12. Middlebury Interactive courses start with fundamental building blocks in four key areas of world-language study: listening comprehension, speaking, reading, and writing. As students progress through the course levels, they deepen their understanding of the target language, continuing to focus on the three modes of communication: interpretive, interpersonal, and presentational. The extensive use of authentic materials (video, audio, images, or texts is intended to provide a contextualized and interactive presentation of the vocabulary and the linguistic structures. In the present paper, we describe the MIL program and the results of a mixed-methods survey and case-study evaluation of its implementation in a broad sample of schools. Technology application is examined with regard to MIL instructional strategies and the present evaluation approach relative to those employed in the literature.

  18. Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade Martensitic Steel

    2013-06-01

    earlier in Fig. 4(a) to construct the corresponding CCT diagram , Fig. 5. The diagram displayed in Fig. 5 is obtained under particular continuous-cooling...TTT and CCT diagrams are necessary, but not sufficient, input for a phase volume-fraction determination procedure. That is, in addition to knowing the...fraction of bainite to the instantaneous temperature for the MIL A46100 HAZ section which was described using TTT and CCT diagrams displayed in Fig. 4(a

  19. Interfacing the septa movement (DC motor) equipment to the PS control system and the MIL1553 bus

    Dehavay, Claude

    1993-01-01

    Continuing the rejuvenation of the PS Control system , it is planned to replace the Single Transceiver Hybrid used to interface the Septa Movement Equipment by a G64 system connected to the VME crate via the MIL1553 bus. This note explains the G64 hardware interface and details the standard message as defined in the Control Protocole for Power Converter, RF and Stepping Motor equipment.

  20. Analysis of a MIL-L-27502 lubricant from a gas-turbine engine test by size-exclusion chromatography

    Jones, W. R., Jr.; Morales, W.

    1983-01-01

    Size exclusion chromatography was used to determine the chemical degradation of MIL-L-27502 oil samples from a gas turbine engine test run at a bulk oil temperature of 216 C. Results revealed a progressive loss of primary ester and additive depletion and the formation of higher molecular weight products with time. The high molecular weight products absorbed strongly in the ultraviolet indicating the presence of chromophoric groups.

  1. Using the Auditory Hazard Assessment Algorithm for Humans (AHAAH) With Hearing Protection Software, Release MIL-STD-1474E

    2013-12-01

    unfolding.” Invited article in NHCA’s Spectrum. 1997 MIL-STD-1474D. (1997). “Department of defense design criteria. Noise limits,” http...Passenger Safety, Washington, DC. Price, G. R. (1997). “Understanding hazard from intense sounds.” Invited seminar to Audiology Department, University of...Putting theory into practice.” In H. M. Borchgrevink (Ed.), Hearing and hearing prophylaxis, Scandinavian Audiology Supplement 16 (pp. 111-121

  2. Petits mils, énorme potentiel : diversifiés, nutritifs et adaptés aux ...

    29 avr. 2016 ... Dans les pays en développement, le manque de diversité dans l'alimentation est l'une des principales causes de la malnutrition et de la prévalence de maladies non transmissibles comme le diabète. La culture des petits mils en complément des cultures existantes pourrait faire partie de la solution.

  3. Fe-MIL-101 exhibits selective cytotoxicity and inhibition of angiogenesis in ovarian cancer cells via downregulation of MMP.

    Wang, Jiaqiang; Chen, Daomei; Li, Bin; He, Jiao; Duan, Deliang; Shao, Dandan; Nie, Minfang

    2016-05-18

    Though metal-organic frameworks (MOFs) have inspired potential applications in biomedicine, cytotoxicity studies of MOFs have been relatively rare. Here we demonstrate for the first time that an easily available MOF, Fe-MIL-101, possesses intrinsic activity against human SKOV3 ovarian cancer cells and suppress the proliferation of SKOV3 cells (IC50 = 23.6 μg mL(-1)) and normal mouse embryonic fibroblasts (BABL-3T3, IC50 = 78.3 μg mL(-1)) cells. It was more effective against SKOV3 cells than typical anticancer drugs such as artesunate (ART, IC50 = 96.9 μg mL(-1)) and oxaliplatin (OXA, IC50 = 64.4 μg mL(-1)), but had less effect on normal BABL-3T3 cells compared with ART (IC50 = 36.6 μg mL(-1)) and OXA (IC50 = 13.8 μg mL(-1)). Fe-MIL-101 induced apoptosis of human umbilical vein endothelial cells (HUVECs) via G0/G1 cell cycle arrest and decreased the mitochondrial membrane potential in HUVECs and induced apoptosis. Furthermore, Fe-MIL-101 exhibited stronger antiangiogenic effects in HUVEC cells than antiangiogenic inhibitor (SU5416) via downregulation the expression of MMP-2/9. Our results reveal a new role of Fe-MIL-101 as a novel, non-toxic anti-angiogenic agent that restricted ovarian tumour growth. These findings could open a new avenue of using MOFs as potential therapeutics in angiogenesis-dependent diseases, including ovarian cancer.

  4. Functionalized MIL-101 with imidazolium-based ionic liquids for the cycloaddition of CO2 and epoxides under mild condition

    Liu, Dan; Li, Gang; Liu, Haiou

    2018-01-01

    A kind of multi-functional sites metal-organic framework (MOF) composite (MIL-101-IMBr) was successfully prepared by post-synthesis modification of MIL-101 with imidazolium-based ionic liquids. The ionic liquids not only functionalize as basic sites but also provide halide anions, which serve as a nucleophile in cycloaddition reaction. The prepared functional MOF materials were characterized by X-ray diffraction, fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, N2 adsorption-desorption and CO2 temperature programmed desorption. The results of fourier transform infrared spectroscopy and energy dispersive spectroscopy show that the MIL-101-IMBr composite was successfully synthesized. The N2 adsorption-desorption results clearly demonstrated that the modified composites still preserve high BET surface area and total pore volume. The composite exhibits high catalytic activity for the cycloaddition of CO2 with epoxides under mild and co-catalyst free conditions. The conversion of propylene oxide was 95.8% and the selectivity of cyclic carbonate was 97.6% under 0.8 MPa at 80 °C for 4 h. Moreover, the catalyst can be used for at least five times.

  5. Solid-State NMR Spectroscopy Proves the Presence of Penta-coordinated Sc Sites in MIL-100(Sc).

    Giovine, Raynald; Volkringer, Christophe; Ashbrook, Sharon E; Trébosc, Julien; McKay, David; Loiseau, Thierry; Amoureux, Jean-Paul; Lafon, Olivier; Pourpoint, Frédérique

    2017-07-18

    Advanced solid-state NMR methods and first-principles calculations demonstrate for the first time the formation of penta-coordinated scandium sites. These coordinatively unsaturated sites were shown during the thermal activation of scandium-based metal-organic frameworks (MOFs). A 45 Sc NMR experiment allows their specific observation in activated Sc 3 BTB 2 (H 3 BTB=1,3,5-tris(4-carboxyphenyl)benzene) and MIL-100(Sc) MOFs. The assignment of the ScO 5 groups is supported by the DFT calculations of NMR parameters. The presence of ScO 5 Lewis acid sites in MIL-100(Sc) explains furthermore its catalytic activity. The first NMR experiment to probe 13 C- 45 Sc distances is also introduced. This advanced solid-state NMR pulse sequence allows the demonstration of the shrinkage of the MIL-100(Sc) network when the activation temperature is raised. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Ammunition Peculiar Equipment (APE) 1995, NIR Propellant Analyzer, to MIL-STD-398, Military Standard Shields, Operational for Ammunition Operations, Criteria for Design of and Tests for Acceptance

    2003-01-01

    ... (SJMAC-DEM) to test the Ammunition Peculiar Equipment (APE) 1995 NIR Propellant Analyzer, to MIL-STD-398, "Military Standard Shields, Operational for Ammunition Operations, Criteria for Design of and Tests for Acceptance...

  7. MIL SPEC 28 Square Foot Fire Burnback and Extinguishment Testing of FireAde, FlameOut II and Hawk ALLFIRE

    Barrett, Kimberly D; Kalberer, Jennifer L

    2008-01-01

    ... for hydrocarbon fuel fires. This report documents the evaluation performed on the fire extinguishing agents FireAde 2000 AFFF LP, FlameOut II and Hawk ALLFORE in accordance with the parameters set forth in Military Specification ( MIL SPEC...

  8. Deposition of CdS nanoparticles on MIL-53(Fe) metal-organic framework with enhanced photocatalytic degradation of RhB under visible light irradiation

    Hu, Longxing, E-mail: hulxhhhb@shu.edu.cn [School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 (China); Deng, Guihua [School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 (China); Lu, Wencong [College of Sciences, Shanghai University, Shanghai 200444 (China); Pang, Siwei; Hu, Xing [School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 (China)

    2017-07-15

    Graphical abstract: The CdS/MIL-53(Fe) photocatalyst has been synthesized by a facile two-step solvothermal method and applied for photocatalytic degradation of organic pollutant RhB under visible light irradiation. - Highlights: • A novel CdS/MIL-53(Fe) photocatalyst was successfully synthesized via a facile two-step solvothermal method. • CdS/MIL-53(Fe) exhibited an enhanced visible-light photocatalytic degradation of RhB in water. • The mechanisms for the formation of CdS/MIL-53(Fe) and photocatalytic degradation of RhB were proposed. - Abstract: A novel composite, CdS/MIL-53(Fe), was successfully fabricated via a facile solvothermal method and characterized with XRD, SEM, TEM, XPS, FT-IR and UV–vis DRS. The results showed that the fabrication was able to result in a good dispersion of CdS nanoparticles onto MIL-53(Fe). The photocatalytic activities of the as-synthesized composite were investigated through the degradation of Rhodamine B (RhB) in water under visible light irradiation. It was found that the composite prepared at the mass ratio of CdS to MIL-53(Fe) of 1.5:1 displayed the highest photocatalytic activity. An approximately 92.5% of photocatalytic degradation of RhB was achieved at 0.5 g/L of 1.5-CdS/MIL dosage, 10 mg/L of initial RhB concentration and 23 °C of reaction temperature under visible light irradiation. The RhB photocatalytic degradation followed well the first-order kinetics equation and the increased catalyst dosage and optimal initial RhB concentration were responsible for the enhanced photocatalytic degradation. Quenching tests revealed that the predominant free radicals in the CdS/MIL-(53)-RhB{sub aq}-visible light system was O{sub 2}{sup −}·; nevertheless, h{sup +} and ·OH also contributed to a certain degree. The enhanced photocatalytic performance was ascribed to the formation of heterojunction structure between CdS and MIL-53(Fe) which significantly suppressed the recombination of photogenerated electron-hole pairs

  9. Deposition of CdS nanoparticles on MIL-53(Fe) metal-organic framework with enhanced photocatalytic degradation of RhB under visible light irradiation

    Hu, Longxing; Deng, Guihua; Lu, Wencong; Pang, Siwei; Hu, Xing

    2017-01-01

    Graphical abstract: The CdS/MIL-53(Fe) photocatalyst has been synthesized by a facile two-step solvothermal method and applied for photocatalytic degradation of organic pollutant RhB under visible light irradiation. - Highlights: • A novel CdS/MIL-53(Fe) photocatalyst was successfully synthesized via a facile two-step solvothermal method. • CdS/MIL-53(Fe) exhibited an enhanced visible-light photocatalytic degradation of RhB in water. • The mechanisms for the formation of CdS/MIL-53(Fe) and photocatalytic degradation of RhB were proposed. - Abstract: A novel composite, CdS/MIL-53(Fe), was successfully fabricated via a facile solvothermal method and characterized with XRD, SEM, TEM, XPS, FT-IR and UV–vis DRS. The results showed that the fabrication was able to result in a good dispersion of CdS nanoparticles onto MIL-53(Fe). The photocatalytic activities of the as-synthesized composite were investigated through the degradation of Rhodamine B (RhB) in water under visible light irradiation. It was found that the composite prepared at the mass ratio of CdS to MIL-53(Fe) of 1.5:1 displayed the highest photocatalytic activity. An approximately 92.5% of photocatalytic degradation of RhB was achieved at 0.5 g/L of 1.5-CdS/MIL dosage, 10 mg/L of initial RhB concentration and 23 °C of reaction temperature under visible light irradiation. The RhB photocatalytic degradation followed well the first-order kinetics equation and the increased catalyst dosage and optimal initial RhB concentration were responsible for the enhanced photocatalytic degradation. Quenching tests revealed that the predominant free radicals in the CdS/MIL-(53)-RhB aq -visible light system was O 2 − ·; nevertheless, h + and ·OH also contributed to a certain degree. The enhanced photocatalytic performance was ascribed to the formation of heterojunction structure between CdS and MIL-53(Fe) which significantly suppressed the recombination of photogenerated electron-hole pairs. Moreover, the

  10. Enhanced catalytic activity over MIL-100(Fe) loaded ceria catalysts for the selective catalytic reduction of NO{sub x} with NH{sub 3} at low temperature

    Wang, Peng [School of Environmental Science and Technology, Dalian University of Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), Dalian 116024 (China); Sun, Hong [School of Environmental & Chemical Engineering, Dalian Jiaotong University, Dalian 116028 (China); Quan, Xie, E-mail: quanxie@dlut.edu.cn [School of Environmental Science and Technology, Dalian University of Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), Dalian 116024 (China); Chen, Shuo [School of Environmental Science and Technology, Dalian University of Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), Dalian 116024 (China)

    2016-01-15

    Highlights: • Nano-ceria was successfully encapsulated into MIL-100(Fe) for the SCR of NO{sub x}. • The incorporated ceria in MIL-100(Fe) showed high content of chemisorbed oxygen. • The added ceria into MIL-100(Fe) improved the formation of adsorbed NO{sub 2} species. • The addition of ceria into MIL-100(Fe) enhanced SCR activity at low temperature. - Abstract: The development of catalysts for selective catalytic reduction (SCR) reactions that are highly active at low temperatures and show good resistance to SO{sub 2} and H{sub 2}O is still a challenge. In this study, we have designed and developed a high-performance SCR catalyst based on nano-sized ceria encapsulated inside the pores of MIL-100(Fe) that combines excellent catalytic power with a metal organic framework architecture synthesized by the impregnation method (IM). Transmission electron microscopy (TEM) revealed the encapsulation of ceria in the cavities of MIL-100(Fe). The prepared IM-CeO{sub 2}/MIL-100(Fe) catalyst shows improved catalytic activity both at low temperatures and throughout a wide temperature window. The temperature window for 90% NO{sub x} conversion ranges from 196 to 300 °C. X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) analysis indicated that the nano-sized ceria encapsulated inside MIL-100(Fe) promotes the production of chemisorbed oxygen on the catalyst surface, which greatly enhances the formation of the NO{sub 2} species responsible for fast SCR reactions.

  11. Magnetic solid phase extraction of typical polycyclic aromatic hydrocarbons from environmental water samples with metal organic framework MIL-101 (Cr) modified zero valent iron nano-particles.

    Zhou, Qingxiang; Lei, Man; Wu, Yalin; Yuan, Yongyong

    2017-03-03

    Metal-organic framework material has been paid more attention because of its good physical and chemical properties. Nanoscale zero valent iron is also in the center of concern recently. Combination of their merits will give impressive results. Present study firstly synthesized a new magnetic nanomaterial nano-scale zero valent iron-functionalized metal-organic framworks MIL-101 (Fe@MIL-101) by co-precipitation method. The morphology and structure of the as-prepared Fe@MIL-101 were characterized by transmission electron microscopy and X-ray diffraction, etc. The experimental results showed that Fe@MIL-101 earned good adsorption ability to polycyclic aromatic hydrocarbons. The limits of detection of developed magnetic solid phase extraction were all below 0.064μgL -1 and precision can be expressed as relative standard deviation (RSD, %) and which was better than 4.4% (n=6). The real water analysis indicated that the spiked recoveries were satisfied, and Fe@MIL-101 earned excellent reusability. All these demonstrated that Fe@MIL-101 exhibited excellent adsorption capability to polycyclic aromatic hydrocarbons and would be a good adsorbent for development of new monitoring methods for environmental pollutants. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Research of mercury removal from sintering flue gas of iron and steel by the open metal site of Mil-101(Cr).

    Zhao, Songjian; Mei, Jian; Xu, Haomiao; Liu, Wei; Qu, Zan; Cui, Yong; Yan, Naiqiang

    2018-06-05

    Metal-organic frameworks (MOFs) adsorbent Mil-101(Cr) was introduced for the removal of elemental mercury from sintering flue gas. Physical and chemical characterization of the adsorbents showed that MIL-101(Cr) had the largest BET surface area, high thermal stability and oxidation capacity. Hg 0 removal performance analysis indicated that the Hg 0 removal efficiency of MIL-101(Cr) increased with the increasing temperature and oxygen content. Besides, MIL-101(Cr) had the highest Hg 0 removal performance compared with Cu-BTC, UiO-66 and activated carbon, which can reach about 88% at 250 °C. The XPS and Hg-TPD methods were used to analyze the Hg 0 removal mechanism; the results show that Hg 0 was first adsorbed on the surface of Mil-101(Cr), and then oxidized by the open metal site Cr 3+ . The generated Hg 2+ was then combined surface adsorbed oxygen of adsorbent to form HgO, and the open metal site Cr 2+ was oxidized to Cr 3+ by surface active oxygen again. Furthermore, MIL-101(Cr) had good chemical and thermal stability. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Ratiometric Fluorescence Sensing and Real-Time Detection of Water in Organic Solvents with One-Pot Synthesis of Ru@MIL-101(Al)-NH2.

    Yin, Hua-Qing; Yang, Ji-Chun; Yin, Xue-Bo

    2017-12-19

    Ratiometric fluorescence detection attracts much attention because of its decreased environmental influence and easy-to-differentiate color and intensity change. Herein, a guest-encapsulation metal-organic framework (MOF), Ru@MIL-NH 2 , is prepared with 2-aminoterephthalic acid, AlCl 3 , and Ru(bpy) 3 2+ by a simple one-pot method for ratiometric fluorescence sensing of water in organic solvents. The rational selection of the excitation wavelength provides dual emission at 465 and 615 nm from Ru@MIL-NH 2 under a single excitation of 300 nm. High sensitivity, low detection limit (0.02% v/v), wide response range (0-100%), and fast response (less than 1 min) are obtained for ratiometric fluorescence sensing of water under single excitation with Ru@MIL-NH 2 as the probe. Moreover, the result of water content is independent of the concentration of Ru@MIL-NH 2 as the merit of ratiometric fluorescence detection. The response mechanism reveals that the protonation of the nitrogen atom of the MIL-NH 2 , the π-conjugation system, and the stable fluorescence of Ru(bpy) 3 2+ achieve the ratiometric fluorescence. The analysis of real spirit samples confirms the proposed method. A test strip is prepared with Ru@MIL-NH 2 for convenient use. We believe that such turn-on ratiometric host-guest MOFs and the rational selection of excitation wavelength will offer guidance for ratiometric fluorescence detection with wide applications.

  14. Fabrication of metal-organic framework MIL-88B films on stainless steel fibers for solid-phase microextraction of polychlorinated biphenyls.

    Wu, Ye-Yu; Yang, Cheng-Xiong; Yan, Xiu-Ping

    2014-03-21

    Metal-organic frameworks (MOFs) have received considerable attention as novel sorbents for sample preparation due to their fascinating structures and functionalities such as large surface area, good thermal stability, and uniform structured nanoscale cavities. Here, we report the application of a thermal and solvent stable MOF MIL-88B with nanosized bipyramidal cages and large surface area for solid-phase microextraction (SPME) of polychlorinated biphenyls (PCBs). Novel MIL-88B coated fiber was fabricated via an in situ hydrothermal growth of MIL-88B film on etched stainless steel fiber. The MIL-88B coated fiber gave large enhancement factors (757-2243), low detection limits (0.45-1.32ngL(-1)), and good linearity (5-200ngL(-1)) for PCBs. The relative standard deviation (RSD) for six replicate extractions of PCBs at 100ngL(-1) on MIL-88B coated fiber ranged from 4.2% to 8.7%. The recoveries for spiked PCBs (10ngL(-1)) in water and soil samples were in the range of 79.7-103.2%. Besides, the MIL-88B coated fiber was stable enough for 150 extraction cycles without significant loss of extraction efficiency. The developed method was successfully applied to the determination of PCBs in water samples and soil samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Dimensions of problem based learning - dialogue and online collaboration in projects

    Andreasen, Lars Birch; Nielsen, Jørgen Lerche

    2013-01-01

    -based learning approach developed in Denmark historically and theoretically, and how it unfolds today discussed through a case of the Danish Master programme in ICT and Learning (MIL), focusing on changes in the roles of teachers as supervisors, and the involvement of students in course and project activities....

  16. Fabrication of core-shell Fe{sub 3}O{sub 4}@MIL-100(Fe) magnetic microspheres for the removal of Cr(VI) in aqueous solution

    Yang, Qingxiang, E-mail: qxyangzz@163.com; Zhao, Qianqian; Ren, ShuangShuang; Lu, Qiongqiong; Guo, Xinmeng; Chen, Zhijun, E-mail: chenzj@zzuli.edu.cn

    2016-12-15

    Facile regeneration of an adsorbent is very important for commercial feasibility. One typical highly porous metal-organic framework (MOF) materials based on MIL-100(Fe) and magnetic iron oxide particles (denoted as MMCs) with diameter about of 350 nm were successfully synthesized. The growth of MIL-100(Fe) shell on the surface of Fe{sub 3}O{sub 4} was utilized precursor as crystal seed via in-situ step hydrothermal reaction. It is a simple way to obtain well organized core-shell MOF composites, compared to the step-by-step method. MMCs were firstly used to uptake of Cr(VI) anions in aqueous solution. Adsorption experiments were carried out in batch sorption mode investigating with the factors of contact time (0–1000 min), pH (from 2 to 12), dose of adsorbent (4–25 mg), and initial Cr(VI) concentration (range from 10 to 100 ppm). - Graphical abstract: One typical highly porous metal-organic framework (MOF) materials based on MIL-100(Fe) and magnetic iron oxide particles (denoted as MMCs) were successfully synthesized. Utilizing Fe{sub 3}O{sub 4} precursor as crystal seed to grow MIL-100(Fe) shell by in-situ step hydrothermal reaction. It is a simple way to obtain core-shell MOF composites. MMCs could effectively uptake of Cr(VI) anions in aqueous solution. - Highlights: • Fe{sub 3}O{sub 4}@MIL-100(Fe) composites with core-shell structure were successfully prepared through a simple method. • The influence factors on Cr(VI) adsorption by Fe{sub 3}O{sub 4}@MIL-100(Fe) were investigated. • Cr(VI) can efficiently adsorbed by Fe{sub 3}O{sub 4}@MIL-100(Fe) composites from aqueous solution.

  17. A sensitive and selective sensor for biothiols based on the turn-on fluorescence of the Fe-MIL-88 metal-organic frameworks-hydrogen peroxide system.

    Sun, Zheng Juan; Jiang, Jun Ze; Li, Yuan Fang

    2015-12-21

    Herein, we present a novel strategy based on a "turn-on" fluorescence system made up of metal-organic frameworks Fe-MIL-88 and H2O2 for detecting biothiols in human serum. The nonfluorescent Fe-MIL-88 gives weak fluorescence in the presence of H2O2. Interestingly, it was found that biothiols such as glutathione (GSH), cysteine (Cys) or homocysteine (Hcy) could induce fluorescence turn-on of the Fe-MIL-88/H2O2 system. Under optimal conditions, the relative fluorescence intensity exhibited a good linear relationship in the range from 50 nM-10 μM for GSH (r = 0.994), 50 nM-10 μM for Cys (r = 0.990), and 50 nM-10 μM (r = 0.992) for Hcy; the detection limits of GSH, Cys and Hcy were 30 nM, 40 nM, and 40 nM respectively. Mechanism investigation reveals that biothiols could associate with Fe-MIL-88 via hydrogen bonding and electrostatic interaction followed by redox reaction between biothiols and Fe(3+) present in the Fe-MIL-88, Fe(3+) was thus reduced to Fe(2+), and then Fe(2+) could efficiently catalyze the decomposition of H2O2 to yield ˙OH radicals through the Fenton reaction. Besides, biothiols were able to reduce H2O2 to produce ˙OH radicals directly. Thus the Fe-MIL-88 as well as biothiols could cooperatively contribute to the activation of H2O2 to generate higher amounts of ˙OH radicals, which in turn oxidize the free ligand terephthalic acid (BDC) outside or within the Fe-MIL-88 structure to strongly fluorescent hydroxylated terephthalic acid (OHBDC), thereby turning on the fluorescence.

  18. Highly efficient Fenton and enzyme-mimetic activities of NH2-MIL-88B(Fe) metal organic framework for methylene blue degradation.

    He, Jianchuan; Zhang, Yao; Zhang, Xiaodan; Huang, Yuming

    2018-03-26

    Here, we show that NH 2 -MIL-88B(Fe) can be used as a peroxidase-like catalyst for Fenton-like degradation of methylene blue (MB) in water. The iron-based NH 2 -MIL-88B(Fe) metal organic framework (MOF) was synthesized by a facile and rapid microwave heating method. It was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and the Brunauer-Emmett-Teller method. The NH 2 -MIL-88B(Fe) MOF possesses intrinsic oxidase-like and peroxidase-like activities. The reaction parameters that affect MB degradation were investigated, including the solution pH, NH 2 -MIL-88B(Fe) MOF and H 2 O 2 concentrations, and temperature. The results show that the NH 2 -MIL-88B(Fe) MOF exhibits a wide working pH range (pH 3.0-11.0), temperature tolerance, and good recyclability for MB removal. Under the optimal conditions, complete removal of MB was achieved within 45 min. In addition, removal of MB was above 80% after five cycles, showing the good recyclability of NH 2 -MIL-88B(Fe). The NH 2 -MIL-88B(Fe) MOF has the features of easy preparation, high efficiency, and good recyclability for MB removal in a wide pH range. Electron spin resonance and fluorescence probe results suggest the involvement of hydroxyl radicals in MB degradation. These findings provide new insight into the application of high-efficient MOF-based Fenton-like catalysts for water purification.

  19. Deposition of CdS nanoparticles on MIL-53(Fe) metal-organic framework with enhanced photocatalytic degradation of RhB under visible light irradiation

    Hu, Longxing; Deng, Guihua; Lu, Wencong; Pang, Siwei; Hu, Xing

    2017-07-01

    A novel composite, CdS/MIL-53(Fe), was successfully fabricated via a facile solvothermal method and characterized with XRD, SEM, TEM, XPS, FT-IR and UV-vis DRS. The results showed that the fabrication was able to result in a good dispersion of CdS nanoparticles onto MIL-53(Fe). The photocatalytic activities of the as-synthesized composite were investigated through the degradation of Rhodamine B (RhB) in water under visible light irradiation. It was found that the composite prepared at the mass ratio of CdS to MIL-53(Fe) of 1.5:1 displayed the highest photocatalytic activity. An approximately 92.5% of photocatalytic degradation of RhB was achieved at 0.5 g/L of 1.5-CdS/MIL dosage, 10 mg/L of initial RhB concentration and 23 °C of reaction temperature under visible light irradiation. The RhB photocatalytic degradation followed well the first-order kinetics equation and the increased catalyst dosage and optimal initial RhB concentration were responsible for the enhanced photocatalytic degradation. Quenching tests revealed that the predominant free radicals in the CdS/MIL-(53)-RhBaq-visible light system was O2-rad ; nevertheless, h+ and rad OH also contributed to a certain degree. The enhanced photocatalytic performance was ascribed to the formation of heterojunction structure between CdS and MIL-53(Fe) which significantly suppressed the recombination of photogenerated electron-hole pairs. Moreover, the reusability of 1.5-CdS/MIL composite was also studied.

  20. Performance of metal-organic framework MIL-101 after surfactant modification in the extraction of endocrine disrupting chemicals from environmental water samples.

    Huang, Zhenzhen; Lee, Hian Kee

    2015-10-01

    The research presented in this paper explored the modification and application of a metal-organic framework, MIL-101, with nonionic surfactant-Triton X-114 in dispersive solid-phase extraction for the preconcentration of four endocrine disrupting chemicals (estrone, 17α-ethynylestradiol, estriol and diethylstilbestrol) from environmental water samples. Triton X-114 molecules could be adsorbed by the hydrophobic surface of the MIL-101 crystals, and thus improved the dispersibility of MIL-101 in aqueous solution by serving as a hydrophilic coating. Cloud point phase separation from Triton X-114 accelerated the separation of extracts from the aqueous matrix. The proposed method combines the favorable attributes of strong adsorption capacity resulting from the porous structure of MIL-101 and self-assembly of Triton X-114 molecules. Post-extraction derivatization using N-methyl-N-(trimethylsilyl)trifluoroacetamide was employed to facilitate the quantitative determination of the extracts by gas chromatography-mass spectrometry. The main factors affecting the preparation of modified MIL-101, and extraction of the analytes, such as the amount of surfactant, the ultrasonic and vortex durations, solution pH and desorption conditions, were investigated in detail. Under the optimized conditions, the present method yielded low limits of detection (0.006-0.023 ng/mL), good linearity from 0.09 to 45 ng/mL (coefficients of determination higher than 0.9980) and acceptable precision (relative standard deviations of 2.2-13%). The surface modified MIL-101 was demonstrated to be effective for the extraction of the selected estrogens from aqueous samples, giving rise to markedly improved extraction performance compared to the unmodified MIL-101. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Amine-functionalized MIL-53(Al)-coated stainless steel fiber for efficient solid-phase microextraction of synthetic musks and organochlorine pesticides in water samples.

    Xie, Lijun; Liu, Shuqin; Han, Zhubing; Jiang, Ruifen; Zhu, Fang; Xu, Weiqin; Su, Chengyong; Ouyang, Gangfeng

    2017-09-01

    The fiber coating is the key part of the solid-phase microextraction (SPME) technique, and it determines the sensitivity, selectivity, and repeatability of the analytical method. In this work, amine (NH 2 )-functionalized material of Institute Lavoisier (MIL)-53(Al) nanoparticles were successfully synthesized, characterized, and applied as the SPME fiber coating for efficient sample pretreatment owing to their unique structures and excellent adsorption properties. Under optimized conditions, the NH 2 -MIL-53(Al)-coated fiber showed good precision, low limits of detection (LODs) [0.025-0.83 ng L -1 for synthetic musks (SMs) and 0.051-0.97 ng L -1 for organochlorine pesticides (OCPs)], and good linearity. Experimental results showed that the NH 2 -MIL-53(Al) SPME coating was solvent resistant and thermostable. In addition, the extraction efficiencies of the NH 2 -MIL-53(Al) coating for SMs and OCPs were higher than those of commercially available SPME fiber coatings such as polydimethylsiloxane, polydimethylsiloxane-divinylbenzene, and polyacrylate. The reasons may be that the analytes are adsorbed on NH 2 -MIL-53(Al) primarily through π-π interactions, electron donor-electron acceptor interactions, and hydrogen bonds between the analytes and organic linkers of the material. Direct immersion (DI) SPME-gas chromatography-mass spectrometry methods based on NH 2 -MIL-53(Al) were successfully applied for the analysis of tap and river water samples. The recoveries were 80.3-115% for SMs and 77.4-117% for OCPs. These results indicate that the NH 2 -MIL-53(Al) coating may be a promising alternative to SPME coatings for the enrichment of SMs and OCPs.

  2. Ship-in-a-bottle CMPO in MIL-101(Cr) for selective uranium recovery from aqueous streams through adsorption.

    De Decker, Jeroen; Folens, Karel; De Clercq, Jeriffa; Meledina, Maria; Van Tendeloo, Gustaaf; Du Laing, Gijs; Van Der Voort, Pascal

    2017-08-05

    Mesoporous MIL-101(Cr) is used as host for a ship-in-a-bottle type adsorbent for selective U(VI) recovery from aqueous environments. The acid-resistant cage-type MOF is built in-situ around N,N-Diisobutyl-2-(octylphenylphosphoryl)acetamide (CMPO), a sterically demanding ligand with high U(VI) affinity. This one-step procedure yields an adsorbent which is an ideal compromise between homogeneous and heterogeneous systems, where the ligand can act freely within the pores of MIL-101, without leaching, while the adsorbent is easy separable and reusable. The adsorbent was characterized by XRD, FTIR spectroscopy, nitrogen adsorption, XRF, ADF-STEM and EDX, to confirm and quantify the successful encapsulation of the CMPO in MIL-101, and the preservation of the host. Adsorption experiments with a central focus on U(VI) recovery were performed. Very high selectivity for U(VI) was observed, while competitive metal adsorption (rare earths, transition metals...) was almost negligible. The adsorption capacity was calculated at 5.32mg U/g (pH 3) and 27.99mg U/g (pH 4), by fitting equilibrium data to the Langmuir model. Adsorption kinetics correlated to the pseudo-second-order model, where more than 95% of maximum uptake is achieved within 375min. The adsorbed U(VI) is easily recovered by desorption in 0.1M HNO 3 . Three adsorption/desorption cycles were performed. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. DEVELOPMENT OF A WELDING PROCEDURE FOR MIL A 46100 ARMOR STEEL JOINTS USING GAS METAL ARC WELDING

    DAVID MAZUERA ROBLEDO; JOHN ALBERTO SUÁREZ GÓMEZ; JORGE ENRIQUE GIRALDO BARRADA

    2011-01-01

    Se desarrolló un procedimiento de soldadura (WPS) para unir láminas de acero para blindaje bajo especificación MIL A46100 usando el proceso GMAW, el cual fue calificado mediante ensayos mecánicos y no destructivos (NDT) de acuerdo con los requerimientos de códigos militares. Los resultados obtenidos fueron comparados con procedimientos de soldadura para este material realizados con el proceso SMAW. Los resultados obtenidos mostraron que el WPS diseñado es una opción viable para la soldadura d...

  4. Pulse gas chromatographic study of adsorption of substituted aromatics and heterocyclic molecules on MIL-47 at zero coverage.

    Duerinck, Tim; Couck, Sarah; Vermoortele, Frederik; De Vos, Dirk E; Baron, Gino V; Denayer, Joeri F M

    2012-10-02

    The low coverage adsorptive properties of the MIL-47 metal organic framework toward aromatic and heterocyclic molecules are reported in this paper. The effect of molecular functionality and size on Henry adsorption constants and adsorption enthalpies of alkyl and heteroatom functionalized benzene derivates and heterocyclic molecules was studied using pulse gas chromatography. By means of statistical analysis, experimental data was analyzed and modeled using principal component analysis and partial least-squares regression. Structure-property relationships were established, revealing and confirming several trends. Among the molecular properties governing the adsorption process, vapor pressure, mean polarizability, and dipole moment play a determining role.

  5. As mulheres em sua família: Mesopotâmia, 2º milênio a.C.

    Brigitte Lion

    2005-12-01

    Full Text Available As fontes cuneiformes do 2º milênio a.C. fornecem uma abundante documentação sobre as mulheres mesopotâmicas. A partir dos códigos de leis e de numerosos arquivos privados, é possível reconstituir a vida das mulheres comuns em seu quadro familiar. Este artigo analisa a condição feminina através dos diferentes costumes matrimoniais, da situação econômica das mulheres, bem como de suas atividades no interior do lar.

  6. Multiple Nebular Gas Reservoirs Recorded by Oxygen Isotope Variation in a Spinel-rich CAI in CO3 MIL 090019

    Simon, J. I.; Simon, S. B.; Nguyen, A. N.; Ross, D. K.; Messenger, S.

    2017-01-01

    We conducted NanoSIMS O-isotopic imaging of a primitive spinel-rich CAI spherule (27-2) from the MIL 090019 CO3 chondrite. Inclusions such as 27-2 are proposed to record inner nebula processes during an epoch of rapid solar nebula evolution. Mineralogical and textural analyses suggest that this CAI formed by high temperature reactions, partial melting, and condensation. This CAI exhibits radial O-isotopic heterogeneity among multiple occurrences of the same mineral, reflecting interactions with distinct nebular O-isotopic reservoirs.

  7. Mise en place d'une collection de ressources génétiques du mil ...

    Le mil est une céréale importante pour l'alimentation humaine. La Côte d'Ivoire représente un des centres de production et de consommation. Afin de collecter, conserver et étudier les variabilités existantes, une seconde mission a été effectuée dans les zones de culture de cette céréale en 1989 et 1990, faisant suite à la ...

  8. Smooth and rapid microwave synthesis of MIL-53(Fe) including superparamagnetic γ-Fe2O3 nanoparticles

    Wengert, Simon; Albrecht, Joachim; Ruoss, Stephen; Stahl, Claudia; Schütz, Gisela; Schäfer, Ronald

    2017-12-01

    MIL-53(Fe) linked to superparamagnetic γ-Fe2O3 nanoparticles was created using time-efficient microwave synthesis. Intermediates as well as the final product have been characterized by Dynamic Light Scattering (DLS), Infrared Spectroscopy (FTIR) and Thermal Gravimetric Analysis (TGA). It is found that this route allows the production of Fe nanoparticles with typical sizes of about 80 nm that are embedded inside the metal-organic structures. Detailed magnetization measurements using SQUID magnetometry revealed a nearly reversible magnetization loop indicating essentially superparamagnetic behavior.

  9. Revisiting the Aluminum Trimesate-based MOF (MIL-96): from Structure Determination to the Processing of Mixed Matrix Membranes for CO2 Capture.

    Benzaqui, Marvin; S. Pillai, Renjith; Sabetghadam, Anahid; Benoit, Virginie; Normand, Pé rine; Marrot, Jerome; Menguy, Nicolas; Montero, David; Shepard, William; Tissot, Antoine; Martineau-Corcos, Charlotte; Sicard, Clé mence; Mihaylov, Mihail; Carn, Florent; Beurroeis, Isabelle; Llewellyn, Philip L.; De Weireld, Guy; Hadjiivanov, Konstantin; Gascon, Jorge; Kapteijn, Freek; Maurin, Guillaume; Steunou, Nathalie; Serre, Christian

    2017-01-01

    A microporous Al trimesate-based metal-organic framework (MOF), denoted MIL-96-(Al), was selected as a porous hybrid filler for the processing of mixed matrix membranes (MMMs) for CO2/N-2 postcombustion separation. First, the structural model of MIL-96-(Al) initially reported was revisited using a combination of synchrotron-based single-crystal X-ray diffraction, solid-state nuclear magnetic resonance spectroscopy, and density functional theory (DFT) calculations. In a second step, pure MIL-96-(Al) crystals differing by their size and aspect ratio, including anisotropic hexagonal platelets and nanoparticles of about 70 nm in diameter, were prepared. Then, a combination of in situ IR spectroscopy, single-gas, and CO2/N-2 coadsorption experiments, calorimetry, and molecular simulations revealed that MIL-96-(Al) nanoparticles show a relatively high CO2 affinity over N-2 owing to strong interactions between CO2 molecules and several adsorption sites such as Al3+ Lewis centers, coordinated water, and hydroxyl groups. Finally, the high compatibility between MIL-96-(Al) nanoparticles and the 6FDA-DAM polymer allowed the processing of homogeneous and defect-free MMMs with a high MOF loading (up to 25 wt %) that outperform pure polymer membranes for CO2/N-2 separation.

  10. Synthesis of highly efficient α-Fe{sub 2}O{sub 3} catalysts for CO oxidation derived from MIL-100(Fe)

    Cui, Lifeng; Zhao, Di; Yang, Yang [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093 (China); Wang, Yuxin [Institute of Applied Biotechnology, Taizhou Vocation & Technical College, Taizhou, Zhejiang 318000 (China); Zhang, Xiaodong, E-mail: fatzhxd@126.com [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093 (China)

    2017-03-15

    Mesoporous hollow α-Fe{sub 2}O{sub 3} bricks were synthesized via a hydrothermal method to create a precursor MIL-100(Fe) and a subsequent calcination process was applied to prepare the Fe{sub 2}O{sub 3} phase. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results showed the morphology of hollow α-Fe{sub 2}O{sub 3} bricks which inherited from the MIL-100(Fe) template. The catalytic activities of hollow α-Fe{sub 2}O{sub 3} bricks for CO oxidation are studied in this work. Due to better low temperature reduction behavior, mesoporous hollow α-Fe{sub 2}O{sub 3} bricks obtained at calcination temperature of 430 °C displayed high catalytic activity and excellent stability with a complete CO conversion temperature (T{sub 100}) of 255 °C. - Graphical abstract: Synthesis of highly efficient α-Fe{sub 2}O{sub 3} catalysts for CO oxidation derived from MIL-100(Fe). - Highlights: • α-Fe{sub 2}O{sub 3} is prepared by the thermolysis of a MIL-100(Fe) template. • The morphology of hollow α-Fe{sub 2}O{sub 3} bricks is inherited from MIL-100(Fe) template. • α-Fe{sub 2}O{sub 3} obtained at calcined temperature of 430 °C displays high activity • Enhanced activity is attributed to crystal plane and reduction behavior.

  11. Self and transport diffusivity of CO2 in the metal-organic framework MIL-47(V) explored by quasi-elastic neutron scattering experiments and molecular dynamics simulations.

    Salles, Fabrice; Jobic, Hervé; Devic, Thomas; Llewellyn, Philip L; Serre, Christian; Férey, Gérard; Maurin, Guillaume

    2010-01-26

    Quasi-elastic neutron scattering measurements are combined with molecular dynamics simulations to determine the self-diffusivity, corrected diffusivity, and transport diffusivity of CO(2) in the metal-organic framework MIL-47(V) (MIL = Materials Institut Lavoisier) over a wide range of loading. The force field used for describing the host/guest interactions is first validated on the thermodynamics of the MIL-47(V)/CO(2) system, prior to being transferred to the investigations of the dynamics. A decreasing profile is then deduced for D(s) and D(o) whereas D(t) presents a non monotonous evolution with a slight decrease at low loading followed by a sharp increase at higher loading. Such decrease of D(t) which has never been evidenced in any microporous systems comes from the atypical evolution of the thermodynamic correction factor that reaches values below 1 at low loading. This implies that, due to intermolecular interactions, the CO(2) molecules in MIL-47(V) do not behave like an ideal gas. Further, molecular simulations enabled us to elucidate unambiguously a 3D diffusion mechanism within the pores of MIL-47(V).

  12. Revisiting the Aluminum Trimesate-based MOF (MIL-96): from Structure Determination to the Processing of Mixed Matrix Membranes for CO2 Capture.

    Benzaqui, Marvin

    2017-11-08

    A microporous Al trimesate-based metal-organic framework (MOF), denoted MIL-96-(Al), was selected as a porous hybrid filler for the processing of mixed matrix membranes (MMMs) for CO2/N-2 postcombustion separation. First, the structural model of MIL-96-(Al) initially reported was revisited using a combination of synchrotron-based single-crystal X-ray diffraction, solid-state nuclear magnetic resonance spectroscopy, and density functional theory (DFT) calculations. In a second step, pure MIL-96-(Al) crystals differing by their size and aspect ratio, including anisotropic hexagonal platelets and nanoparticles of about 70 nm in diameter, were prepared. Then, a combination of in situ IR spectroscopy, single-gas, and CO2/N-2 coadsorption experiments, calorimetry, and molecular simulations revealed that MIL-96-(Al) nanoparticles show a relatively high CO2 affinity over N-2 owing to strong interactions between CO2 molecules and several adsorption sites such as Al3+ Lewis centers, coordinated water, and hydroxyl groups. Finally, the high compatibility between MIL-96-(Al) nanoparticles and the 6FDA-DAM polymer allowed the processing of homogeneous and defect-free MMMs with a high MOF loading (up to 25 wt %) that outperform pure polymer membranes for CO2/N-2 separation.

  13. Eu(III)-functionalized MIL-124 as fluorescent probe for highly selectively sensing ions and organic small molecules especially for Fe(III) and Fe(II).

    Xu, Xiao-Yu; Yan, Bing

    2015-01-14

    A layerlike MOF (MIL-124, orGa2(OH)4(C9O6H4)) has been prepared and chosen as a parent compound to encapsulate Eu(3+) cations by one uncoordinated carbonyl group in its pores. The Eu(3+)-incorporated sample (Eu(3+)@MIL-124) is fully characterized, which shows excellent luminescence and good fluorescence stability in water or other organic solvents. Subsequently, we choose Eu(3+)@MIL-124 as sensitive probe for sensing metal ions, anions, and organic small molecules because of its robust framework. Studying of the luminescence properties reveals that the complex Eu(3+)@MIL-124 was developed as a highly selective and sensitive probe for detection of Fe(3+) (detection limit, 0.28 μM) and Fe(2+) ions through fluorescence quenching of Eu(3+) and MOF over other metal ions. In connection to this, a probable sensing mechanism was also discussed in this paper. In addition, when Eu(3+)@MIL-124 was immersed in the different anions solutions and organic solvents, it also shows highly selective for Cr2O7(2-)(detection limit, 0.15 μM)and acetone. Remarkably, it is the first Eu-doped MOF to exhibit an excellent ability for the detection of Fe(3+) and Fe(2+) in an aqueous environment without any structural disintegration of the framework.

  14. An amino-functionalized magnetic framework composite of type Fe3O4-NH2@MIL-101(Cr) for extraction of pyrethroids coupled with GC-ECD.

    He, Xi; Yang, Wei; Li, Sijia; Liu, Yu; Hu, Baichun; Wang, Ting; Hou, Xiaohong

    2018-01-24

    An amino-functionalized magnetic framework composite of type Fe 3 O 4 -NH 2 @MIL-101(Cr) was synthesized using a solvothermal method. The material was characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption, and magnetometry. The composite combines the advantages of amino-modified Fe 3 O 4 and MIL-101(Cr). The presence of amino groups facilitates the fairly specific adsorption of pyrethroids. The composite was employed as a sorbent for magnetic solid phase extraction of five pyrethroids from environmental water samples. Following desorption with acidified acetone, the pyrethroids were quantified by gas chromatography with electron capture detection. The detection limits for bifenthrin, fenpropathrin, λ-cyhalothrin, permethrin, and deltamethrin range from 5 to 9 pg·mL -1 . The method is rapid, accurate, and highly sensitive. The molecular interactions and free binding energies between MIL-101(Cr) and the five pyrethroids were calculated by means of molecular docking. Graphical abstract A novel functionalized magnetic framework composite of type Fe 3 O 4 -NH 2 @MIL-101(Cr) was synthesized. It was applied as a sorbent for magnetic solid phase extraction of pyrethroids prior to their quantitation by gas chromatography with electron capture detection. The molecular interactions of analytes and MIL-101(Cr) were studied.

  15. H5PV2Mo10O40 encapsulated in MIL-101(Cr): facile synthesis and characterization of rationally designed composite materials for efficient decontamination of sulfur mustard.

    Li, Yanqin; Gao, Qi; Zhang, Lijuan; Zhou, Yunshan; Zhong, Yuxu; Ying, Ying; Zhang, Mingcai; Huang, Chunqian; Wang, Yong'an

    2018-04-24

    Currently extensive effort is compulsively expended to decontaminate efficiently banned chemical war agents. In this work, H5PV2Mo10O40 molecules have been encapsulated in mesoporous MIL-101(Cr), which features two types of mesoporous cages (internal diameters of 29 Å and 34 Å) and microporous windows (diameters of 12 Å and 16 Å), leading to the formation of a new composite H5PV2Mo10O40@MIL-101(Cr) through a simple impregnation method. The composite was characterized thoroughly by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, TG/DTA, and textural analysis thereby confirming the encapsulation of the H5PV2Mo10O40 into MIL-101(Cr). The decontamination efficiency of sulfur mustard (4 μL HD in 40 μL of petroleum ether) by 20 mg of the composite is found to be 97.39% in 120 min under ambient conditions. GC-MS analysis on the decontaminated products using 2-chloroethyl ethyl sulfide (CEES), which has been widely used as a simulant of sulfur mustard, showed that MIL-101(Cr) just decontaminates CEES by adsorption, while CEES can be decontaminated under ambient conditions by a synergetic combination of adsorption of MIL-101(Cr) and subsequent chemical oxidation degradation to nontoxic 2-chloroethyl ethyl sulfoxide (CEESO) due to the presence of highly dispersed H5PV2Mo10O40 within the composites.

  16. MIL-125-NH2@TiO2 Core-Shell Particles Produced by a Post-Solvothermal Route for High-Performance Photocatalytic H2 Production.

    Zhang, Bingxing; Zhang, Jianling; Tan, Xiuniang; Shao, Dan; Shi, Jinbiao; Zheng, Lirong; Zhang, Jing; Yang, Guanying; Han, Buxing

    2018-05-02

    Metal-organic frameworks (MOFs) have proven to be an interesting class of sacrificial precursors of functional inorganic materials for catalysis, energy storage, and conversion applications. However, the controlled synthesis of MOF-derived materials with desirable compositions, structures, and properties still remains a big challenge. Herein, we propose a post-solvothermal route for the outer-to-inner loss of organic linkers from MOF, which is simple, rapid, and controllable and can be operated at temperature much lower than that of the commonly adopted pyrolysis method. By such a strategy, the MIL-125-NH 2 particles coated by TiO 2 nanosheets were produced, and the thickness of TiO 2 shell can be easily tuned. The MIL-125-NH 2 @TiO 2 core-shell particles combine the advantages of highly active TiO 2 nanosheets, MIL-125-NH 2 photosensitizer, plenty of linker defects and oxygen vacancies, and mesoporous structure, which allows them to be utilized as photocatalysts for the visible-light-driven hydrogen production reaction. It is remarkable that the hydrogen evolution rate by MIL-125-NH 2 @TiO 2 can be enhanced 70 times compared with the pristine MIL-125-NH 2 . Such a route can be easily applied to the synthesis of different kinds of MOF-derived functional materials.

  17. Learning

    Mohsen Laabidi

    2014-01-01

    Full Text Available Nowadays learning technologies transformed educational systems with impressive progress of Information and Communication Technologies (ICT. Furthermore, when these technologies are available, affordable and accessible, they represent more than a transformation for people with disabilities. They represent real opportunities with access to an inclusive education and help to overcome the obstacles they met in classical educational systems. In this paper, we will cover basic concepts of e-accessibility, universal design and assistive technologies, with a special focus on accessible e-learning systems. Then, we will present recent research works conducted in our research Laboratory LaTICE toward the development of an accessible online learning environment for persons with disabilities from the design and specification step to the implementation. We will present, in particular, the accessible version “MoodleAcc+” of the well known e-learning platform Moodle as well as new elaborated generic models and a range of tools for authoring and evaluating accessible educational content.

  18. Construcción de un anfiteatro subterráneo de mil plazas

    Hereng, J. M.

    1963-02-01

    Full Text Available The Arts and Crafts School of Paris was in need of an auditorium, with accommodation for one thousand persons, suitable for lessons and lectures. Owing to lack of space, it was decided to build it underground, below one of the courtyards. The choice of roof shape was an ellipsoid of revolution, whose major axis is inclined to the horizontal. The maximum diameter is 32 ms and maximum height is 10 ms. The thickness of the roof structure is 50 cms along the lower part, and 20 cms near the crown. This solution was of special interest as it overcame simultaneously two difficulties; namely, the foundation, when this has to be based on fill soil, and the non-interference with the illumination of nearby buildings. In this case the loading on the soil is always less than 380 grams per cm-, even assuming a local settlement of the soil over any area of 20 ms in diameter. Concrete has been transported to the required sites by means of compressed air chutes, with the result that the rate of concreting has not been interfered with. Formwork has been carefully thought out, especially over the zones where the floor surface changes into the auditorium vault. The tubular structure supporting the formwork of the vault has been erected with columns which are normal to the inclined diametral plane of the surface of revolution. Owing to this unusual arrangement, the staff working at the site have often lost their sense of balance.El Conservatorio de Artes y Oficios de París necesitaba un anfiteatro capaz para mil plazas, utilizable para clases y conferencias. Por falta de espacio se decidió construirlo subterráneo en uno de los patios. La solución adoptada fue la de un elipsoide de revolución de eje mayor inclinado respecto de la horizontal con 32 m de diámetro y 10 de altura máxima; el espesor en la parte inferior es de 50 cm y en la superior de 20 centímetros. Esta solución es de particular interés, ya que solventaba de una vez dos problemas: el de

  19. Interaction of methanol with the flexible metal-organic framework MIL-53(Fe) observed by inelastic neutron scattering

    Munn, Alexis S.; Ramirez-Cuesta, Anibal J.; Millange, Franck; Walton, Richard I.

    2013-01-01

    Highlights: • A spectroscopic signature of guest-induced swelling of a flexible MOF has been identified. • Librations of the linker contribute to pore opening of the MOF structure. • Complementary in situ powder XRD shows changes in long-range order during guest uptake. - Abstract: In situ powder X-ray diffraction and thermogravimetry show that the iron(III) carboxylate material MIL-53(Fe) expands in two steps upon exposure to methanol vapour to give a ‘half open’ phase and then a fully expanded structure; these correspond to the uptake of one and two molar equivalents of methanol, respectively. This knowledge allows interpretation of inelastic neutron scattering (INS) spectra, measured using TOSCA at ISIS, of the solid loaded with various amounts of water, methanol or d3-methanol (CD 3 OH), aided also by DFT simulation of INS spectra of the analogous MIL-53(Al) structure. The key signature of the expansion and contraction of the structure is the shift of bands in the 400 cm −1 region: these are assigned as due to the librations of the terephthalate rings, involving motions that result in distortion of the aromatic ring and a rocking motion of the aromatic ring about the bonds to the carboxylate groups

  20. Chelating agent-free, vapor-assisted crystallization method to synthesize hierarchical microporous/mesoporous MIL-125 (Ti).

    McNamara, Nicholas D; Hicks, Jason C

    2015-03-11

    Titanium-based microporous heterogeneous catalysts are widely studied but are often limited by the accessibility of reactants to active sites. Metal-organic frameworks (MOFs), such as MIL-125 (Ti), exhibit enhanced surface areas due to their high intrinsic microporosity, but the pore diameters of most microporous MOFs are often too small to allow for the diffusion of larger reactants (>7 Å) relevant to petroleum and biomass upgrading. In this work, hierarchical microporous MIL-125 exhibiting significantly enhanced interparticle mesoporosity was synthesized using a chelating-free, vapor-assisted crystallization method. The resulting hierarchical MOF was examined as an active catalyst for the oxidation of dibenzothiophene (DBT) with tert-butyl hydroperoxide and outperformed the solely microporous analogue. This was attributed to greater access of the substrate to surface active sites, as the pores in the microporous analogues were of inadequate size to accommodate DBT. Moreover, thiophene adsorption studies suggested the mesoporous MOF contained larger amounts of unsaturated metal sites that could enhance the observed catalytic activity.

  1. DEVELOPMENT OF A WELDING PROCEDURE FOR MIL A 46100 ARMOR STEEL JOINTS USING GAS METAL ARC WELDING

    DAVID MAZUERA ROBLEDO

    2011-01-01

    Full Text Available Se desarrolló un procedimiento de soldadura (WPS para unir láminas de acero para blindaje bajo especificación MIL A46100 usando el proceso GMAW, el cual fue calificado mediante ensayos mecánicos y no destructivos (NDT de acuerdo con los requerimientos de códigos militares. Los resultados obtenidos fueron comparados con procedimientos de soldadura para este material realizados con el proceso SMAW. Los resultados obtenidos mostraron que el WPS diseñado es una opción viable para la soldadura de blindajes de acero MIL A 46100. Además, con el WPS diseñado se obtuvo una reducción en el ancho de la zona afectada térmicamente (ZAT que debería conducir a un mejor desempeño en servicio de los blindajes de acuerdo con los resultados de estudios previos. Finalmente, se encontró un incremento en la energía absorbida en los ensayos de impacto Charpy V comparada con la de soldaduras realizadas con el proceso SMAW.

  2. Pyrolytic in situ magnetization of metal-organic framework MIL-100 for magnetic solid-phase extraction.

    Huo, Shu-Hui; An, Hai-Yan; Yu, Jing; Mao, Xue-Feng; Zhang, Zhe; Bai, Lei; Huang, Yan-Feng; Zhou, Peng-Xin

    2017-09-29

    In this study, we report a facile, environmental friendly fabrication of a type of magnetic metal-organic framework (MOF) MIL-100 that can be used for magnetic solid-phase extraction (MSPE). The magnetic MOF composites were fabricated using in situ calcination method. The as-synthesized materials exhibited both high porosity and magnetic characteristics. They used for the MSPE of polycyclic aromatic hydrocarbons (PAHs) from water samples. Such MOF-based magnetic solid-phase extraction in combination with gas chromatography equipped with a flame ionization detector (GC-FID), exhibited wide linearity (0.02-250μgL -1 ), low detection limits (4.6-8.9ngL -1 ), and high enrichment factors (452-907) for PAHs. The relative standard deviations (RSDs) for intra- and inter-day extractions of PAHs were ranging from 1.7% to 9.8% and 3.8% to 9.2%, respectively. The recoveries for spiked PAHs (1μgL -1 ) in water samples were in the range of 88.5% to 106.6%. The results showed that the special anion-π orbital (electron donor-acceptor) interaction and π-π stacking between magnetic MIL-100 and PAHs play an important role in the adsorption of PAHs. Copyright © 2017. Published by Elsevier B.V.

  3. Poverty and the Millennium Development Goals Pobreza e Metas de Desenvolvimento para o Milênio

    G. J. Ebrahim

    2007-12-01

    apresentada como um desafio para muitos países em desenvolvimento. Em um ambiente físico de privação se desenvolve a cultura da pobreza com sua prevalência de doença, desagregação social, violência dentro e fora dos lares e dependência de álcool e drogas. No meio urbano pobre a inserção no comportamento de risco é comum. As principais vítimas de privações são as mulheres, as crianças, os idosos e os fracos. Evidências mostram os efeitos deletérios de a criança crescer em meio à pobreza. Ação corretiva consiste em uma tarefa árdua, cara e nem sempre bem sucedida. O despertar da consciência social global provocado pela dura realidade do pobre urbano vivendo lado a lado em íntimo contato com o consumo opulento e evidente tem persuadido líderes mundiais e economistas a mobilizar a opinião pública. Um encontro de lideres mundiais ocorrido nas Nações Unidas, no ano 2000, propôs e acordou Metas de Desenvolvimento para o Milênio. As metas são dirigidas não apenas para a pobreza per se mas também os seus efeitos. A data limite para a conquista das metas de desenvolvimento do milênio foi estabelecida para o ano 2015. Os progressos em torno dessas metas têm sido toscos e dependem da maturidade política nacional.

  4. Multi-View Multi-Instance Learning Based on Joint Sparse Representation and Multi-View Dictionary Learning.

    Li, Bing; Yuan, Chunfeng; Xiong, Weihua; Hu, Weiming; Peng, Houwen; Ding, Xinmiao; Maybank, Steve

    2017-12-01

    In multi-instance learning (MIL), the relations among instances in a bag convey important contextual information in many applications. Previous studies on MIL either ignore such relations or simply model them with a fixed graph structure so that the overall performance inevitably degrades in complex environments. To address this problem, this paper proposes a novel multi-view multi-instance learning algorithm (MIL) that combines multiple context structures in a bag into a unified framework. The novel aspects are: (i) we propose a sparse -graph model that can generate different graphs with different parameters to represent various context relations in a bag, (ii) we propose a multi-view joint sparse representation that integrates these graphs into a unified framework for bag classification, and (iii) we propose a multi-view dictionary learning algorithm to obtain a multi-view graph dictionary that considers cues from all views simultaneously to improve the discrimination of the MIL. Experiments and analyses in many practical applications prove the effectiveness of the M IL.

  5. Dye-sensitized MIL-101 metal organic frameworks loaded with Ni/NiO{sub x} nanoparticles for efficient visible-light-driven hydrogen generation

    Liu, Xin-Ling; Wang, Rong; Yuan, Yu-Peng, E-mail: yupengyuan@ahu.edu.cn, E-mail: cxue@ntu.edu.sg [School of Chemistry and Chemical Engineering, and Innovation Lab for Clean Energy and Green Catalysis, Anhui University, Hefei 230036 (China); Zhang, Ming-Yi [Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025 (China); Xue, Can, E-mail: yupengyuan@ahu.edu.cn, E-mail: cxue@ntu.edu.sg [Solar Fuels Lab, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2015-10-01

    The Ni/NiO{sub x} particles were in situ photodeposited on MIL-101 metal organic frameworks as catalysts for boosting H{sub 2} generation from Erythrosin B dye sensitization under visible-light irradiation. The highest H{sub 2} production rate of 125 μmol h{sup −1} was achieved from the system containing 5 wt. % Ni-loaded MIL-101 (20 mg) and 30 mg Erythrosin B dye. Moreover, the Ni/NiO{sub x} catalysts show excellent stability for long-term photocatalytic reaction. The enhancement on H{sub 2} generation is attributed to the efficient charge transfer from photoexcited dye to the Ni catalyst via MIL-101. Our results demonstrate that the economical Ni/NiO{sub x} particles are durable and active catalysts for photocatalytic H{sub 2} generation.

  6. Dye-sensitized MIL-101 metal organic frameworks loaded with Ni/NiOx nanoparticles for efficient visible-light-driven hydrogen generation

    Xin-Ling Liu

    2015-10-01

    Full Text Available The Ni/NiOx particles were in situ photodeposited on MIL-101 metal organic frameworks as catalysts for boosting H2 generation from Erythrosin B dye sensitization under visible-light irradiation. The highest H2 production rate of 125 μmol h−1 was achieved from the system containing 5 wt. % Ni-loaded MIL-101 (20 mg and 30 mg Erythrosin B dye. Moreover, the Ni/NiOx catalysts show excellent stability for long-term photocatalytic reaction. The enhancement on H2 generation is attributed to the efficient charge transfer from photoexcited dye to the Ni catalyst via MIL-101. Our results demonstrate that the economical Ni/NiOx particles are durable and active catalysts for photocatalytic H2 generation.

  7. Effect of Amine-Functionalized MIL-53 Metal Organic Frameworks on the Performance of Poly(4-methyl-1-pentyne Membrane in CO2/CH4 Separation Gas Mixture

    Reza Abedini

    2015-06-01

    Full Text Available The effect of NH2-MIL 53 metal organic framework (MOF on gas transport properties of poly(4-methyl-1-pentyne (PMP was investigated. Various characterization methods such as FTIR, DSC, SEM and gas adsorption test as well as a series of CO2/CH4 gas separation tests (i.e., pure and mixed gas test were conducted in order to determine the effect of ligand functionalization (–NH2 on the properties of the prepared mixed matrix membranes and their gas transport characteristics. The results of DSC showed that glass transition temperature (Tg increased by increasing NH2-MIL 53 loading. The SEM images also demonstrated that the NH2-MIL 53 particles were dispersed well in the PMP matrix with no noticeable agglomeration. The gas adsorption test of NH2-MIL 53 particles revealed there was a selective adsorption behavior with respect to CO2. It was also found that, incorporation of NH2-MIL 53 into the PMP resulted in an increase in gas permeability (especially towards CO2 and a higher CO2/CH4 selectivity. Adding 30 wt% NH2-MIL 53 into the polymer matrix increased CO2 permeability and CO2/CH4 selectivity of the mixed gas from 83.35 to 210.21 barrer and 7.61 to 19.88, respectively. Rising the temperature from 30 to 60°C led to the permeability increment of both CO2 and CH4 in the mixed gas test, while the CO2/CH4 selectivity decreased. Moreover, the results showed that amino groups required no regeneration and their performance did not decline during 120 h of permeation test. A comparison between the permeation data and those calculated from permeation models revealed that the Bruggeman model could fit the CO2 permeability data better than the Maxwell and Lewis models.

  8. A Mixed Matrix Membrane of Poly (4-methyl-1-pentyne Filled with MIL 53 Particles and Its Application in Carbon Dioxide and Nitrogen Separation

    Reza Abedini

    2016-05-01

    Full Text Available The performance of poly (4-metyl-1-pentyne as mixed matrix membrane (MMM mixed with MIL 53 particles was studied to separate mixtures of carbon dioxide and nitrogen. MIL 53 particles was added to the polymer matrix with 10, 20 and 30 weight percentages. The adsorption of CO2 and N2 gases by MIL 53 was evaluated and the adsorption data was analyzed by Langmuir equation. Structure and thermal/mechanical properties of prepared membranes were characterized by means of FTIR, SEM, TGA and elongation test. Moreover, the gas permeation properties of membranes were studied by measuring the permeation of pure CO2 and N2. Furthermore, for accurate understanding of the gas permeation properties of the membranes, diffusion and solution coefficient of gases in neat membrane and MMMs were calculated using modified time-lag method. The results from TGA analysis showed that the degradation temperature of MMMs was enhanced and increased to 348ºC for membrane containing 30 wt% of MIL 53. The SEM images also illustrated a relatively uniform dispersion of particles with proper polymer/filler interfaces in the polymer matrix. The gas permeation results revealed that the permeability of both gases (especially CO2 increased with increasing MIL 53 loading, in which the permeability of CO2 increased from 98.74 Barrer in neat membrane to 217.65 Barrer in MMM containing 30 wt% filler. Moreover, calculation of CO2/N2 selectivity depicted that the selectivity enhanced from 16.66 to 22.70. Finally, the performance of MMMs was compared with Robeson’s upper bound in CO2/N2 separation and results showed that the MMM having 30 wt% of MIL 53 took over the Robeson bound.

  9. High performance liquid chromatography of substituted aromatics with the metal-organic framework MIL-100(Fe): Mechanism analysis and model-based prediction.

    Qin, Weiwei; Silvestre, Martin Eduardo; Li, Yongli; Franzreb, Matthias

    2016-02-05

    Metal-organic framework (MOF) MIL-100(Fe) with well-defined thickness was homogenously coated onto the outer surface of magnetic microparticles via a liquid-phase epitaxy method. The as-synthesized MIL-100(Fe) was used as stationary phase for high-performance liquid chromatography (HPLC) and separations of two groups of mixed aromatic hydrocarbons (toluene, styrene and p-xylene; acetanilide, 2-nirtoaniline and 1-naphthylamine) using methanol/water as mobile phase were performed to evaluate its performance. Increasing water content of the mobile phase composition can greatly improve the separations on the expense of a longer elution time. Stepwise elution significantly shortens the elution time of acetanilide, 2-nirtoaniline and 1-naphthylamine mixtures, while still achieving a baseline separation. Combining the experimental results and in-depth modeling using a recently developed chromatographic software (ChromX), adsorption equilibrium parameters, including the affinities and maximum capacities, for each analyte toward the MIL-100(Fe) are obtained. In addition, the pore diffusivity of aromatic hydrocarbons within MIL-100(Fe) was determined to be 5×10(-12)m(2)s(-1). While the affinities of MIL-100(Fe) toward the analyte molecules differs much, the maximum capacities of the analytes are in a narrow range with q*MOFmax,toluene=3.55molL(-1), q*MOFmax,styrene or p-xylene=3.53molL(-1), and q*MOFmax,anilines=3.12molL(-1) corresponding to approximately 842 toluene and 838 styrene or p-xylene, and 740 aniline molecules per MIL-100(Fe) unit cell, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Photoelectrochemical detection of the herbicide clethodim by using the modified metal-organic framework amino-MIL-125(Ti)/TiO2

    Jin, Dangqin; Yu, Liangyun; Xu, Qin; Hu, Xiaoya

    2015-01-01

    We describe a sensitive photoelectrochemical (PEC) sensor for the determination of the herbicide clethodim. The PEC sensor was constructed by using amino-MIL-125/TiO 2 (MIL stands for Materials from Institute Lavoisier), an amino-functionalized metal-organic framework (MOF) modified with TiO2. The amino-MIL-125/TiO 2 was synthesized by a simple one-step solvothermal method and placed on a glassy carbon electrode where it displays photoelectrocatalytic activity. Scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and X-ray diffractometry (XRD) were used to characterize the amino-MIL-125/TiO2. In the sensing process, amino-MIL-125/TiO 2 is illuminated by visible light to produce electrons. These excited electrons are delivered to the glassy carbon electrode, leaving positively charged holes (h+) on the surface of the amino-MIL-125/TiO 2 . The holes react with H 2 O to generate hydroxy radicals (•OH). Clethodim rapidly attacks the hydroxy radicals and improves the efficiency of charge separation, this leading to an enhanced photocurrent. Under the optimal experimental conditions, this photoelectrochemical method enables clethodim to be quantified in the concentration range from 0.2 to 25 μmol L −1 , with a detection limit (3 S/N) of 10 nmol L −1 . The assay was applied to the determination of clethodim in soil samples, and results were in acceptable agreement with data obtained by liquid chromatography/mass spectrometry. (author)

  11. Adsorption of 1,2-dichlorobenzene and 1,2,4-trichlorobenzene in nano- and microsized crystals of MIL-101(Cr): static and dynamic gravimetric studies.

    Bullot, Laetitia; Vieira-Sellaï, Ludivine; Chaplais, Gérald; Simon-Masseron, Angélique; Daou, Toufic Jean; Patarin, Joël; Fiani, Emmanuel

    2017-12-01

    This work aims to highlight the promising adsorption capacity and kinetic of (poly)chlorobenzene pollutants in the hybrid MIL-101(Cr) type material for technological uses in industrial waste exhaust decontamination. The influence of the MIL-101(Cr) crystal size (nano- and microcrystals) on the adsorption behavior was studied in static and dynamic modes. For this purpose, crystals of MIL-101(Cr) in nano- and micrometric sizes were synthesized and fully characterized. Their sorption properties regarding 1,2-dichlorobenzene were examined using gravimetric method in dynamic (p/p° = 0.5) and static (p/p° = 1) modes at room temperature. 1,2,4-trichlorobenzene adsorption was only performed under static mode because of its too low vapor pressure. 1,2-dichlorobenzene and 1,2,4-trichlorobenzene were used to mimic 2,3-dichlorodibenzo-p-dioxin and 1,2,3,4-tetrachlorodibenzo-p-dioxin, respectively, and more largely dioxin compounds. Adsorptions of these probes were successfully carried out in nano- and microcrystals of MIL-101(Cr). Indeed, in static mode (p/p° = 1) and at room temperature, nanocrystals adsorb 2266 molecules of 1,2-dichlorobenzene and 2093 molecules of 1,2,4-trichlorobenzene per unit cell, whereas microcrystals adsorb 1871 molecules of 1,2-dichlorobenzene and 1631 molecules of 1,2,4-trichlorobenzene per unit cell. In dynamic mode, the 1,2-dichlorobenzene adsorbed amounts are substantially similar to those obtained in static mode. However, the adsorption kinetics are different because of a different scheme of diffusivity of the adsorbate between the two modes. To the best of our knowledge, these adsorption capacities of MIL-101(Cr) as adsorbent for polychlorobenzenes trapping have never been referenced. MIL-101(Cr) appears as a promising material for technological uses in industrial waste exhaust decontamination.

  12. Brønsted instead of Lewis acidity in functionalized MIL-101Cr MOFs for efficient heterogeneous (nano-MOF) catalysis in the condensation reaction of aldehydes with alcohols.

    Herbst, Annika; Khutia, Anupam; Janiak, Christoph

    2014-07-21

    Porous chromium(III) 2-nitro-, 2-amino-, and nonfunctionalized terephthalate (MIL-101Cr) metal organic frameworks are heterogeneous catalysts for diacetal formation from benzaldehyde and methanol (B-M reaction) as well as other aldehydes and alcohols. MIL-101Cr-NO2 obtained by direct reaction between CrO3 and 2-nitro-terephthalate showed the highest activity with 99% conversion in the B-M reaction in 90 min and turnover numbers of 114. The activity decreased in the order MIL-101Cr-NO2 > MIL-101Cr > MIL-101Cr-NH2. Within different samples of nonfunctionalized MIL-101Cr the activity increased with surface area. Methanol gas sorption of the different MIL materials correlates with the BET surface area and pore volume but not with the diacetalization activity. Benzaldehyde adsorption from heptane showed no significant difference for the different MILs. Gas sorption studies of CD3CN to probe for a higher Lewis acidity in MIL-101Cr-NO2 remained inconclusive. A high B-M catalytic activity of wet MIL-101Cr-NO2 excluded significant contributions from coordinatively unsaturated Lewis-acid sites. pH measurements of methanol dispersions of the MIL materials gave the most acidic pH (as low as 1.9) for MIL-101Cr-NO2, which significantly increased over MIL-101Cr (3.0) to MIL-101Cr-NH2 (3.3). The increase in acidity is of short range or a surface effect to the heterogeneous MIL particles as protons dissociating from the polarized aqua ligands (Cr-OH2) have to stay near the insoluble counteranionic framework. The variation in Brønsted acidity of MIL-101Cr-NO2 > MIL-101Cr ≈ MIL-101Cr-NH2 correlates with the withdrawing effect of NO2 and the diacetalization activity. The catalytic B-M activity of soluble, substitution-inert, and acidic Cr(NO3)3·9H2O supports the Brønsted-acid effect of the MIL materials. Filtration and centrifugation experiments with MIL-101Cr-NO2 revealed that about 2/3 of the catalytic activity comes from nano-MOF particles with a diameter below 200 nm. The MIL

  13. Validation of MIL-F-9490D. General Specification for Flight Control System for Piloted Military Aircraft. Volume III. C-5A Heavy Logistics Transport Validation

    1977-04-01

    subjected to extreme environmental climatic tests, including the IdL,-T-5289 test requirement. 5.1.9.2 Invulnerability to Lightning Strikes and Static...specified in Paragraph 3.2.3.2.1. The hydi aulic computing elements were designed to the requirements of MIL-C- 5503 and �-H-8775. I 297 L...and climate in any area of the world using MI,- STD-210, FAA-T3O-(49C, and MIL-F-9490, as applicable. Environmental areas included solar radiation

  14. Propuesta de una planificación estratégica e indicadores de desempeño para la empresa Talleres Mil Usos

    Gómez Zhiminaicela, Johanna Elizabeth; Redrován Reyes, Mayra Elizabeth

    2014-01-01

    En el presente trabajo se realizó una propuesta de Planificación Estratégica y medidores de desempeño para la empresa Talleres Mil Usos, se analizó los diferentes parámetros de la Planificación Estratégica y su importancia dentro de las organizaciones, también se planteó objetivos, estrategias e indicadores desempeño para verificar su desempeño laboral. In this work was carried out a Strategic Planning proposal and performance mediators for the company Talleres Mil Usos, looking at differe...

  15. Radiative cooling test facility and performance evaluation of 4-MIL aluminized polyvinyl fluoride and white-paint surfaces

    Kruskopf, M.S.; Berdahl, P.; Martin, M.; Sakkal, F.; Sobolewski, M.

    1980-11-01

    A test facility designed to measure the amount of radiative cooling a specific material or assembly of materials will produce when exposed to the sky is described. Emphasis is placed upon assemblies which are specifically designed to produce radiative cooling and which therefore offer promise for the reduction of temperatures and/or humidities in occupied spaces. The hardware and software used to operate the facility are documented and the results of the first comprehensive experiments are presented. A microcomputer-based control/data acquisition system was employed to study the performance of two prototype radiator surfaces: 4-mil aluminized polyvinyl fluoride (PVF) and white painted surfaces set below polyethylene windscreens. The cooling rates for materials tested were determined and can be approximated by an equation (given). A computer model developed to simulate the cooling process is presented. (MCW)

  16. Post-modified acid-base bifunctional MIL-101(Cr) for one-pot deacetalization-Knoevenagel reaction

    Mu, Manman [Tianjin University, School of Science (China); Yan, Xilong; Li, Yang; Chen, Ligong, E-mail: lgchen@tju.edu.cn [Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) (China)

    2017-04-15

    A novel and convenient approach for the construction of the bifunctional MIL-101 material bearing sulfonic acid and amino groups was established via the post-synthetic modification. This material possesses high BET surface area (1446 m{sup 2}/g) and large pore volume (0.77 cm{sup 3}/g). Significantly, this material could serve as a bifunctional heterogeneous catalyst and was initially employed for one-pot deacetalization-Knoevenagel reaction, exhibiting excellent catalytic performance (yield 99.74%). More importantly, it can be easily recovered and reused at least three times. Finally, our proposed catalytic mechanism indicated that amino and the sulfonic acid groups played a synergistic effect on this one-pot deacetalization-Knoevenagel reaction.

  17. Feature and Region Selection for Visual Learning.

    Zhao, Ji; Wang, Liantao; Cabral, Ricardo; De la Torre, Fernando

    2016-03-01

    Visual learning problems, such as object classification and action recognition, are typically approached using extensions of the popular bag-of-words (BoWs) model. Despite its great success, it is unclear what visual features the BoW model is learning. Which regions in the image or video are used to discriminate among classes? Which are the most discriminative visual words? Answering these questions is fundamental for understanding existing BoW models and inspiring better models for visual recognition. To answer these questions, this paper presents a method for feature selection and region selection in the visual BoW model. This allows for an intermediate visualization of the features and regions that are important for visual learning. The main idea is to assign latent weights to the features or regions, and jointly optimize these latent variables with the parameters of a classifier (e.g., support vector machine). There are four main benefits of our approach: 1) our approach accommodates non-linear additive kernels, such as the popular χ(2) and intersection kernel; 2) our approach is able to handle both regions in images and spatio-temporal regions in videos in a unified way; 3) the feature selection problem is convex, and both problems can be solved using a scalable reduced gradient method; and 4) we point out strong connections with multiple kernel learning and multiple instance learning approaches. Experimental results in the PASCAL VOC 2007, MSR Action Dataset II and YouTube illustrate the benefits of our approach.

  18. Institutionalizing Blended Learning into Joint Training: A Case Study and Ten Recommendations

    2014-12-01

    mail.mil pbockelman@mesh.dsci.com ABSTRACT In 2011, the Joint Staff J7 (Joint Training) directorate initiated the Continuum of eLearning project in...Orlando, FL. 14. ABSTRACT In 2011, the Joint Staff J7 (Joint Training) directorate initiated the Continuum of eLearning project in order to integrate...dispersed organizations still poses significant challenges. The Joint Staff J7, Deputy Director for Joint Training initiated the Continuum of eLearning

  19. Superior Activity of Isomorphously Substituted MOFs with MIL-100(M=Al, Cr, Fe, In, Sc, V) Structure in the Prins Reaction: Impact of Metal Type

    Gómez-Pozuelo, G.; Cabello, C. P.; Opanasenko, Maksym; Horáček, Michal; Čejka, Jiří

    2017-01-01

    Roč. 82, č. 1 (2017), s. 152-159 ISSN 2192-6506 R&D Projects: GA ČR GA14-07101S Institutional support: RVO:61388955 Keywords : impregnated mcm-41 catalyst * organic frameworks mil-100 * solid acid catalyst Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.797, year: 2016

  20. Chitosan capped nanoscale Fe-MIL-88B-NH2 metal-organic framework as drug carrier material for the pH responsive delivery of doxorubicin

    Sivakumar, P.; Priyatharshni, S.; Nagashanmugam, K. B.; Thanigaivelan, A.; Kumar, K.

    2017-08-01

    In recent years nanoscale metal-organic frameworks (NMOFs) are contributing as an effective material for use in drug delivery and imaging applications due to their porous surfaces and easy surface modifications. In this work, Fe-MIL-88B-NH2 NMOFs were successfully synthesized on facile hydrothermal route and 2-aminoterephthalic acid (NH2-BDC) was employed as a bridging ligand to activate amine functional groups on the surface. Amine functional groups not only serve as a structure stabilizing agent but also enhance the loading efficiency of the doxorubicin (DOX) anticancer drug. A pH responsive DOX release was realized by introducing a positively charged chitosan (Chi) capping layer. Upon Chi-coating, cleavage was observed in the Fe-MIL-88B-NH2 structure at acidic pH, while gel-like insoluble structure was formed at basic pH. By utilizing this phenomenon, a pH responsive DOX release system was developed by using Chi capped Fe-MIL-88B-NH2 NMOFs under the designed pH (4.0-8.0). The results suggest the Chi capped Fe-MIL-88B-NH2 can be a promising candidate for future pH responsive drug delivery systems.

  1. Preparation of MIL-53(Fe)-Reduced Graphene Oxide Nanocomposites by a Simple Self-Assembly Strategy for Increasing Interfacial Contact: Efficient Visible-Light Photocatalysts.

    Liang, Ruowen; Shen, Lijuan; Jing, Fenfen; Qin, Na; Wu, Ling

    2015-05-13

    In this work, MIL-53(Fe)-reduced graphene oxide (M53-RGO) nanocomposites have been successfully fabricated by a facile and efficient electrostatic self-assembly strategy for improving the interfacial contact between RGO and the MIL-53(Fe). Compared with D-M53-RGO (direct synthesis of MIL-53(Fe)-reduced graphene oxide nanocomposites via one-pot solvothermal approach), M53-RGO nanocomposites exhibit improved photocatalytic activity compared with the D-M53-RGO under identical experimental conditions. After 80 min of visible light illumination (λ ≥ 420 nm), the reduction ratio of Cr(VI) is rapidly increased to 100%, which is also higher than that of reference sample (N-doped TiO2). More significantly, the M53-RGO nanocomposites are proven to perform as bifunctional photocatalysts with considerable activity in the mixed systems (Cr(VI)/dyes) under visible light, which made it a potential candidate for industrial wastewater treatment. Combining with photoelectrochemical analyses, it could be revealed that the introduction of RGO would minimize the recombination of photogenerated electron-hole pairs. Additionally, the effective interfacial contact between MIL-53(Fe) and RGO surface would further accelerate the transfer of photogenerated electrons, leading to the enhancement of photocatalytic activity of M53-RGO toward photocatalytic reactions. Finally, a possible photocatalytic reaction mechanism is also investigated in detail.

  2. Metal organic framework g-C3N4/MIL-53(Fe) heterojunctions with enhanced photocatalytic activity for Cr(VI) reduction under visible light

    Huang, Wenyuan; Liu, Ning; Zhang, Xiaodong; Wu, Minghong; Tang, Liang

    2017-12-01

    In this study, hybrid nanocomposites based on Fe-based MOF and graphitic carbon nitride (g-C3N4) were developed by a facile solvothermal method. The as-prepared materials were characterized by XRD, FESEM, TEM, XPS and PL analysis. It was showed that the introduction of a certain amount of g-C3N4 on the surface of MIL-53(Fe) would improve the separation and migration rate of photo-induced charges, consequently resulting in the boost of photocatalytic efficiency. Compared with g-C3N4 and MIL-53(Fe), the CMFe composites displayed more excellent visible light-resposive photocatalytic activity for the reduction of Cr(VI). The optimal doping content of g-C3N4 in g-C3N4/MIL-53(Fe) composite was determined to be 3.0 wt%, and it showed about 2.1 and 2.0 times as high photocatalytic efficiency for the reduction of Cr(VI) as that of pure g-C3N4 and MIL-53(Fe), respectively. Meanwhile, the composite exhibited good reusability and stability in the process of cyclic experiments. A possible photocatalytic reaction mechanism was also investigated in detail by the related electrochemical analysis.

  3. Enhanced catalytic activity over MIL-100(Fe) loaded ceria catalysts for the selective catalytic reduction of NOx with NH₃ at low temperature.

    Wang, Peng; Sun, Hong; Quan, Xie; Chen, Shuo

    2016-01-15

    The development of catalysts for selective catalytic reduction (SCR) reactions that are highly active at low temperatures and show good resistance to SO2 and H2O is still a challenge. In this study, we have designed and developed a high-performance SCR catalyst based on nano-sized ceria encapsulated inside the pores of MIL-100(Fe) that combines excellent catalytic power with a metal organic framework architecture synthesized by the impregnation method (IM). Transmission electron microscopy (TEM) revealed the encapsulation of ceria in the cavities of MIL-100(Fe). The prepared IM-CeO2/MIL-100(Fe) catalyst shows improved catalytic activity both at low temperatures and throughout a wide temperature window. The temperature window for 90% NOx conversion ranges from 196 to 300°C. X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) analysis indicated that the nano-sized ceria encapsulated inside MIL-100(Fe) promotes the production of chemisorbed oxygen on the catalyst surface, which greatly enhances the formation of the NO2 species responsible for fast SCR reactions. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. The Onset and Duration of Action of 0.2% Lidocaine in a One-per-Mil Tumescent Solution for Hand Surgery.

    Prasetyono, Theddeus O H; Lestari, Puri A

    2016-05-01

    One-per-mil tumescent solution, which contains 0.2% lidocaine with 1:1,000,000 epinephrine, has been reported to be clinically effective for hand surgery under local anesthesia. However, it was lacking in its basic pharmacokinetics profile in regard to the onset of action (OOA) and duration of action (DOA). A randomized, double-blind study was conducted on 12 volunteers who met the inclusion criteria from October to November 2014. All volunteers had their right and left ring finger pulps injected with either one-per-mil solution or 2% lidocaine. Semmes-Weinstein and two-point discrimination tests were used to test sensation. Visual analogue scale was recorded at the time when the finger lost its sensation and when it regained normal sensation to measure the OOA and DOA. The data were then analyzed with a paired t-test and a Wilcoxon signed-rank test. The OOA and DOA of 2% plain lidocaine were 1 minute and 99.67 minutes, respectively. Meanwhile, 0.2% lidocaine in a one-per-mil tumescent solution showed an OOA of 5 minutes and a DOA of 186.83 minutes. The OOA of 0.2% lidocaine in a one-per-mil tumescent solution is statistically shorter than 2% plain lidocaine (P=0.04); while its DOA is statistically longer than 2% plain lidocaine (Pmil tumescent solution is statistically and clinically superior to 2% plain lidocaine in achieving longer duration of local anesthesia.

  5. Green synthesis and evaluation of an iron-based metal-organic framework MIL-88B for efficient decontamination of arsenate from water.

    Hou, Shuliang; Wu, Yi-Nan; Feng, Lingyu; Chen, Wei; Wang, Ying; Morlay, Catherine; Li, Fengting

    2018-02-13

    Iron-containing metal-organic frameworks (MOFs) have gradually emerged as environmentally benign alternatives for reducing the levels of environmental contamination because of their advantages, such as readily obtained raw materials with low cost, nontoxic metal source with good biocompatibility, and distinguished physicochemical features e.g., high porosity, framework flexibility, and semiconductor properties. In this study, we reported an innovative strategy for synthesizing an iron-based MOF, MIL-88B, at room temperature. The novelty of this strategy was the use of ethanol as solvent and the pretreatment of dry milling with neither the bulk use of a toxic organic solvent nor the addition of extremely dangerous hydrofluoric acid or strong alkali. The synthesized MIL-88B(Fe) was evaluated as a sorbent for removing arsenate in water and it exhibited high adsorption capacity (156.7 mg g -1 ) at a low dosage. The removal capacity of trace arsenate on MIL-88B(Fe) was 32.3 mg g -1 at a low equilibrium concentration (6.4 μg L -1 ), which satisfied the arsenic threshold for drinking water. The results of Fourier transform infrared and X-ray photoelectron spectroscopy indicated that the As(v) molecules bonded with the oxygen molecules, which were coordinated with FeO clusters in the framework. This work presented the potential use of the up-scaled MIL-88B as an excellent sorbent for purifying arsenate-contaminated water.

  6. Synthesis and sonocatalytic performance of a ternary magnetic MIL-101(Cr)/RGO/ZnFe2O4 nanocomposite for degradation of dye pollutants.

    Nirumand, Ladan; Farhadi, Saeed; Zabardasti, Abedin; Khataee, Alireza

    2018-04-01

    In this study, new ternary magnetic MIL-101(Cr)/RGO/ZnFe 2 O 4 catalyst (with 30% wt of ZnFe 2 O 4 ) was synthesized via a hydrothermal route for sonodegradation of organic dyes. The structural, optical and magnetic properties of the nanocomposite were detected by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy (UV-visible), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectroscopy, vibrating sample magnetometer (VSM), atomic force microscopy (AFM), Raman spectroscopy and BET surface area analysis. To evaluate the sonocatalytic activity of the as-prepared MIL-101(Cr)/RGO/ZnFe 2 O 4 nanocomposite, the H 2 O 2 -assisted degradation of organic dyes such as congo red (CR), methylene blue (MB), Rhodamine B (RhB) and methyl orange (MO) in aqueous solution was studied under ultrasound irradiation. The obtained results indicated that the ternary MIL-101(Cr)/RGO/ZnFe 2 O 4 nanocomposite had better performance for sonodegradation of these dyes than MIL-101(Cr)/RGO, pure MIL-101(Cr) or ZnFe 2 O 4 . The enhanced sonocatalytic performance of the as-prepared ternary nanocomposite could be attributed to the fast generation and separation of charge carriers (electrons and holes) in ZnFe 2 O 4 and MIL-101(Cr) and their transfer to the surface of graphene sheets. Moreover, the relatively high specific surface area of the MIL-101(Cr)/rGO and magnetic property of ZnFe 2 O 4 improve the degradation efficiency of the dyes. The recovery of the ternary magnetic sonocatalyst from treated water could be easily achieved using an external magnetic field. The main influence factors on the sonocatalytic activity such as catalyst dosage and dye initial concentration were also investigated. The trapping experiments indicated that OH radicals are the prominent active species in dye degradation. In addition, the reusability test, was also carried out to ensure the stability of the employed sonocatalyst

  7. Elucidating the breathing of the metal-organic framework MIL-53(Sc) with ab initio molecular dynamics simulations and in situ X-ray powder diffraction experiments.

    Chen, Linjiang; Mowat, John P S; Fairen-Jimenez, David; Morrison, Carole A; Thompson, Stephen P; Wright, Paul A; Düren, Tina

    2013-10-23

    Ab initio molecular dynamics (AIMD) simulations have been used to predict structural transitions of the breathing metal-organic framework (MOF) MIL-53(Sc) in response to changes in temperature over the range 100-623 K and adsorption of CO2 at 0-0.9 bar at 196 K. The method has for the first time been shown to predict successfully both temperature-dependent structural changes and the structural response to variable sorbate uptake of a flexible MOF. AIMD employing dispersion-corrected density functional theory accurately simulated the experimentally observed closure of MIL-53(Sc) upon solvent removal and the transition of the empty MOF from the closed-pore phase to the very-narrow-pore phase (symmetry change from P2(1)/c to C2/c) with increasing temperature, indicating that it can directly take into account entropic as well as enthalpic effects. We also used AIMD simulations to mimic the CO2 adsorption of MIL-53(Sc) in silico by allowing the MIL-53(Sc) framework to evolve freely in response to CO2 loadings corresponding to the two steps in the experimental adsorption isotherm. The resulting structures enabled the structure determination of the two CO2-containing intermediate and large-pore phases observed by experimental synchrotron X-ray diffraction studies with increasing CO2 pressure; this would not have been possible for the intermediate structure via conventional methods because of diffraction peak broadening. Furthermore, the strong and anisotropic peak broadening observed for the intermediate structure could be explained in terms of fluctuations of the framework predicted by the AIMD simulations. Fundamental insights from the molecular-level interactions further revealed the origin of the breathing of MIL-53(Sc) upon temperature variation and CO2 adsorption. These simulations illustrate the power of the AIMD method for the prediction and understanding of the behavior of flexible microporous solids.

  8. Effects of ductile phase volume fraction on the mechanical properties of Ti-Al3Ti metal-intermetallic laminate (MIL) composites

    Price, Richard D.; Jiang Fengchun; Kulin, Robb M.; Vecchio, Kenneth S.

    2011-01-01

    Research highlights: → Residual Al improves the mechanical properties of Ti-Al 3 Ti MIL composites. → Residual Al can eliminate intermetallic centerline delaminations in MILs. → Low levels of residual Al increase fracture toughness in MIL composites. → MIL stiffness, strength, and fracture toughness can be optimized at low Al levels. - Abstract: Metal-intermetallic laminate (MIL) composites consisting of alternating layers of Ti, Al, and the intermetallic Al 3 Ti have been fabricated by reactive foil sintering in open air. Six initially identical stacks of alternating Ti-3Al-2.5 V and 1100-Al foils were processed for different lengths of time, yielding specimens with different metal and intermetallic volume fractions. Their mechanical properties have been investigated with an emphasis on the effect of residual Al at the intermetallic centerline on composite strength and fracture toughness, as well as fracture and failure modes. Samples were cut from each composite plate (in layer orientations parallel and perpendicular to the intended load direction) for mechanical testing in compression and four-point bending under quasi-static and high-rate loading conditions. Examination of the damaged specimens and their fracture surfaces by optical and scanning electron microscopy was performed to establish a correlation between the failure mechanisms present, composite strength, and microstructure. Results indicated that regardless of loading direction, cracks always initiated in the intermetallic region, rarely at the centerline, and crack propagation and failure were heavily influenced by the thickness of the residual aluminum layers. There is an ideal residual aluminum volume fraction that represents the amount of ductile reinforcement that maximizes the combined properties of strength, toughness and stiffness.

  9. Facile synthesis of highly efficient amorphous Mn-MIL-100 catalysts: The formation mechanism and the structure changes during the application for CO oxidation.

    Zhang, Xiaodong; Li, Hongxin; Lv, Xutian; Xu, Jingcheng; Wang, Yuxin; He, Chi; Liu, Ning; Yang, Yiqiong; Wang, Yin

    2018-04-13

    A comprehensive study was carried out on amorphous metal-organic frameworks Mn-MIL-100 as efficient catalysts towards CO oxidation. This study focuses on explaining the crystalline-amorphous-crystalline transformations during thermolysis process of Mn-MIL-100 and studying the structure changes during the reaction process for CO oxidation. A possible formation mechanism of amorphous Mn-MIL-100 was proposed. Amorphous Mn-MIL-100 obtained by calcination at 250°C (a-Mn-250) showed a smaller specific surface area (4 m2/g), but displayed a high catalytic activity. Furthermore, the structure of amorphous Mn-MIL-100 was labile during the reaction process. When used a-Mn-250 were treated with reaction atmosphere at high temperature (named used a-Mn-250-S), the amorphous catalysts transformed to Mn2O3. Meanwhile, BET surface area (164 m2/g) and the catalytic performance both sharply increased. In addition, used a-Mn-250-S catalyst transformed from Mn2O3 to Mn3O4, resulting in the slightly decrease of catalytic activity under the presence of 1 vol% water vapor in the stream. A schematic of the structure changes during the reaction process was proposed. The achievement of our synthesis relies on the increase of BET surface area using CO as retreatment atmosphere, and the enhanced catalytic activity was attributed to the unique structure, a high quantity of surface active oxygen species, oxygen vacancies and good low temperature reduction behavior. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Sustainable Catalysis: Rational Pd Loading on MIL-101Cr-NH2 for More Efficient and Recyclable Suzuki–Miyaura Reactions

    Pascanu, Vlad; Yao, Qingxia; Bermejo Gómez, Antonio; Gustafsson, Mikaela; Yun, Yifeng; Wan, Wei; Samain, Louise; Zou, Xiaodong; Martín-Matute, Belén

    2013-01-01

    Palladium nanoparticles have been immobilized into an amino-functionalized metal–organic framework (MOF), MIL-101Cr-NH2, to form Pd@MIL-101Cr-NH2. Four materials with different loadings of palladium have been prepared (denoted as 4-, 8-, 12-, and 16 wt %Pd@MIL-101Cr-NH2). The effects of catalyst loading and the size and distribution of the Pd nanoparticles on the catalytic performance have been studied. The catalysts were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), N2-sorption isotherms, elemental analysis, and thermogravimetric analysis (TGA). To better characterize the palladium nanoparticles and their distribution in MIL-101Cr-NH2, electron tomography was employed to reconstruct the 3D volume of 8 wt %Pd@MIL-101Cr-NH2 particles. The pair distribution functions (PDFs) of the samples were extracted from total scattering experiments using high-energy X-rays (60 keV). The catalytic activity of the four MOF materials with different loadings of palladium nanoparticles was studied in the Suzuki–Miyaura cross-coupling reaction. The best catalytic performance was obtained with the MOF that contained 8 wt % palladium nanoparticles. The metallic palladium nanoparticles were homogeneously distributed, with an average size of 2.6 nm. Excellent yields were obtained for a wide scope of substrates under remarkably mild conditions (water, aerobic conditions, room temperature, catalyst loading as low as 0.15 mol %). The material can be recycled at least 10 times without alteration of its catalytic properties. PMID:24265270

  11. Synthesis and structure determination of new open-framework chromium carboxylate MIL-105 or CrIII(OH).{O2C-C6(CH3)4-CO2}.nH2O

    Serre, Christian; Millange, Franck; Devic, Thomas; Audebrand, Nathalie; Van Beek, Wouter

    2006-01-01

    Two new three-dimensional chromium(III) dicarboxylate, MIL-105 or Cr III (OH).{O 2 C-C 6 (CH 3 ) 4 -CO 2 }.nH 2 O, have been obtained under hydrothermal conditions, and their structures solved using X-ray powder diffraction data. Both solids are structural analogs of the known Cr benzenedicarboxylate compound (MIL-53). Both contain trans corner-sharing CrO 4 (OH) 2 octahedral chains connected by tetramethylterephthalate di-anions. Each chain is linked by the ligands to four other chains to form a three-dimensional framework with an array of 1D pores channels. The pores of the high temperature form of the solid, MIL-105ht, are empty. However, MIL-105ht re-hydrates at room temperature to finally give MIL-105lt with pores channels filled with free water molecules (lt: low temperature form; ht: high temperature form). The thermal behaviour of the two solids has been investigated using TGA. Crystal data for MIL-105ht: monoclinic space group C2/c with a = 19.653(1) A, b = 9.984(1) A, c = 6.970(1) A, β = 110.67(1) o and Z = 4. Crystal data for MIL-105lt: orthorhombic space group Pnam with a = 17.892(1) A, b = 11.165(1) A, c = 6.916(1) A and Z = 4

  12. Studying Antarctic Ordinary Chondrite (OC) and Miller Range (MIL) Nakhlite Meteorites to Assess Carbonate Formation on Earth and Mars

    Evans, Michael Ellis

    Carbonates are found in meteorites collected from Antarctica. The stable isotope composition of these carbonates records their formation environment on either Earth or Mars. The first research objective of this dissertation is to characterize the delta18O and delta 13C values of terrestrial carbonates formed on Ordinary Chondrites (OCs) collected in regions near known martian meteorites. The second objective is to characterize the delta18O and delta13C values of martian carbonates from Nakhlites collected from the Miller Range (MIL). The third objective is to assess environmental changes on Mars since the Noachian period. The OCs selected had no pre-terrestrial carbonates so any carbonates detected are presumed terrestrial in origin. The study methodology is stepped extraction of CO2 created from phosphoric acid reaction with meteorite carbonate. Stable isotope results show that two distinct terrestrial carbonate species (Ca-rich and Fe/Mg-rich) formed in Antarctica on OCs from a thin-film of meltwater containing dissolved CO2. Carbon isotope data suggests the terrestrial carbonates formed in equilibrium with atmospheric CO2 delta 13C = -7.5‰ at >15°C. The wide variation in delta 18O suggests the carbonates did not form in equilibrium with meteoric water alone, but possibly formed from an exchange of oxygen isotopes in both water and dissolved CO2. Antarctica provides a model for carbonate formation in a low water/rock ratio, near 0°C environment like modern Mars. Nakhlite parent basalt formed on Mars 1.3 billion years ago and the meteorites were ejected by a single impact approximately 11 million years ago. They traveled thru space before eventually falling to the Earth surface 10,000-40,000 years ago. Nakhlite samples for this research were all collected from the Miller Range (MIL) in Antarctica. The Nakhlite stable isotope results show two carbonate species (Ca-rich and Fe/Mg-rich) with a range of delta18O values that are similar to the terrestrial OC

  13. Martian fluid and Martian weathering signatures identified in Nakhla, NWA 998 and MIL 03346 by halogen and noble gas analysis

    Cartwright, J. A.; Gilmour, J. D.; Burgess, R.

    2013-03-01

    We report argon (Ar) noble gas, Ar-Ar ages and halogen abundances (Cl, Br, I) of Martian nakhlites Nakhla, NWA 998 and MIL 03346 to determine the presence of Martian hydrous fluids and weathering products. Neutron-irradiated samples were either crushed and step-heated (Nakhla only), or simply step-heated using a laser or furnace, and analysed for noble gases using an extension of the 40Ar-39Ar technique to determine halogen abundances. The data obtained provide the first isotopic evidence for a trapped fluid that is Cl-rich, has a strong correlation with 40ArXS (40ArXS = 40Armeasured - 40Arradiogenic) and displays 40ArXS/36Ar of ˜1000 - consistent with the Martian atmosphere. This component was released predominantly in the low temperature and crush experiments, which may suggest a fluid inclusion host. For the halogens, we observe similar Br/Cl and I/Cl ratios between the nakhlites and terrestrial reservoirs, which is surprising given the absence of crustal recycling, organic matter and frequent fluid activity on Mars. In particular, Br/Cl ratios in our Nakhla samples (especially olivine) are consistent with previously analysed Martian weathering products, and both low temperature and crush analyses show a similar trend to the evaporation of seawater. This may indicate that surface brines play an important role on Mars and on halogen assemblages within Martian meteorites and rocks. Elevated I/Cl ratios in the low temperature NWA 998 and MIL 03346 releases may relate to in situ terrestrial contamination, though we are unable to distinguish between low temperature terrestrial or Martian components. Whilst estimates of the amount of water present based on the 36Ar concentrations are too high to be explained by a fluid component alone, they are consistent with a mixed-phase inclusion (gas and fluid) or with shock-implanted Martian atmospheric argon. The observed fluid is dilute (low salinity, but high Br/Cl and I/Cl ratios), contains a Martian atmospheric component

  14. Challenges in first-principles NPT molecular dynamics of soft porous crystals: A case study on MIL-53(Ga)

    Haigis, Volker; Belkhodja, Yacine; Coudert, François-Xavier; Vuilleumier, Rodolphe; Boutin, Anne

    2014-08-01

    Soft porous crystals present a challenge to molecular dynamics simulations with flexible size and shape of the simulation cell (i.e., in the NPT ensemble), since their framework responds very sensitively to small external stimuli. Hence, all interactions have to be described very accurately in order to obtain correct equilibrium structures. Here, we report a methodological study on the nanoporous metal-organic framework MIL-53(Ga), which undergoes a large-amplitude transition between a narrow- and a large-pore phase upon a change in temperature. Since this system has not been investigated by density functional theory (DFT)-based NPT simulations so far, we carefully check the convergence of the stress tensor with respect to computational parameters. Furthermore, we demonstrate the importance of dispersion interactions and test two different ways of incorporating them into the DFT framework. As a result, we propose two computational schemes which describe accurately the narrow- and the large-pore phase of the material, respectively. These schemes can be used in future work on the delicate interplay between adsorption in the nanopores and structural flexibility of the host material.

  15. Synthesis of highly efficient Mn2O3 catalysts for CO oxidation derived from Mn-MIL-100

    Zhang, Xiaodong; Li, Hongxin; Hou, Fulin; Yang, Yang; Dong, Han; Liu, Ning; Wang, Yuxin; Cui, Lifeng

    2017-07-01

    In this work, metal-organic frameworks (MOFs) Mn-MIL-100 were first prepared, which were next used as templates to obtain the irregular porous Mn2O3 cubes through calcination with air at different temperature. The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), H2-temperature program reduction (H2-TPR) and X-ray photoelectron spectroscopic (XPS). The catalytic activity for CO oxidation over Mn2O3 catalysts was investigated. It was found that calcination temperature had a strong effect on the structure and catalytic activity of Mn2O3 catalyst. Mn2O3 catalyst obtained by calcined at 700 °C (Mn2O3-700) showed a smaller specific surface area, but displayed a high catalytic activity and excellent stability with a complete CO conversion temperature (T98) of 240 °C, which was attributed to the unique structure, a high quantity of surface active oxygen species, smaller particle size, oxygen vacancies and good low temperature reduction behavior. The effect of water vapor on catalytic activity was also examined. The introduction of water vapor to the feedstock induced a positive effect on CO oxidation over Mn2O3-700 catalyst. Furthermore, no obvious drop is observed in activity over catalysts even in the presence of water vapor during 48 h.

  16. Improved Gas Metal Arc Welding Multi-Physics Process Model and Its Application to MIL A46100 Armor-Grade Steel Butt-welds

    2014-01-01

    decomposition during cooling is the so-called CCT (Continuous Cooling Transformation) diagram. In the case of CCT diagrams , the thermal histories...the start and the finish of the aforementioned phase transformations) are characterized by constant cooling rates. An example of the CCT diagram for...Ac1 Bs Fs Ff –0.01K/s1.6 K/s Figure 11. MIL A46100 continuous- cooling-transformation ( CCT ) diagram corresponding to the TTT diagram displayed in

  17. O terceiro milênio e o paradigma da informação 10.5007/1518-2924.1999v4n8p35

    Edilene Vieira Scotti

    1999-01-01

    Full Text Available Reflexão sobre o papel da informação, do conhecimento e das tecnologias de informação na sociedade atual. Discorre sobre as relações da informação com o poder e com a sociedade. Aborda a Sociedade da Informação e os desafios profissionais no terceiro milênio.

  18. Thin Film Nanocomposite Membrane Filled with Metal-Organic Frameworks UiO-66 and MIL-125 Nanoparticles for Water Desalination

    Mohammed Kadhom

    2017-06-01

    Full Text Available Knowing that the world is facing a shortage of fresh water, desalination, in its different forms including reverse osmosis, represents a practical approach to produce potable water from a saline source. In this report, two kinds of Metal-Organic Frameworks (MOFs nanoparticles (NPs, UiO-66 (~100 nm and MIL-125 (~100 nm, were embedded separately into thin-film composite membranes in different weight ratios, 0%, 0.05%, 0.1%, 0.15%, 0.2%, and 0.3%. The membranes were synthesized by the interfacial polymerization (IP of m-phenylenediamine (MPD in aqueous solution and trimesoyl chloride (TMC in an organic phase. The as-prepared membranes were characterized by scanning electron microscopy (SEM, transmission electron microscopy (TEM, contact angle measurement, attenuated total reflection Fourier transform infrared (ATR FT-IR spectroscopy, and salt rejection and water flux assessments. Results showed that both UiO-66 and MIL-125 could improve the membranes’ performance and the impacts depended on the NPs loading. At the optimum NPs loadings, 0.15% for UiO-66 and 0.3% for MIL-125, the water flux increased from 62.5 L/m2 h to 74.9 and 85.0 L/m2 h, respectively. NaCl rejection was not significantly affected (UiO-66 or slightly improved (MIL-125 by embedding these NPs, always at >98.5% as tested at 2000 ppm salt concentration and 300 psi transmembrane pressure. The results from this study demonstrate that it is promising to apply MOFs NPs to enhance the TFC membrane performance for desalination.

  19. CoFe2O4@MIL-100(Fe) hybrid magnetic nanoparticles exhibit fast and selective adsorption of arsenic with high adsorption capacity

    Yang, Ji-Chun; Yin, Xue-Bo

    2017-01-01

    In this study, we report the synthesis and application of mesoporous CoFe2O4@MIL-100(Fe) hybrid magnetic nanoparticles (MNPs) for the simultaneous removal of inorganic arsenic (iAs). The hybrid adsorbent had a core-shell and mesoporous structure with an average diameter of 260 nm. The nanoscale size and mesoporous character impart a fast adsorption rate and high adsorption capacity for iAs. In total, 0.1 mg L−1 As(V) and As(III) could be adsorbed within 2 min, and the maximum adsorption capacities were 114.8 mg g−1 for As(V) and 143.6 mg g−1 for As(III), higher than most previously reported adsorbents. The anti-interference capacity for iAs adsorption was improved by the electrostatic repulsion and size exclusion effects of the MIL-100(Fe) shell, which also decreased the zero-charge point of the hybrid absorbent for a broad pH adsorption range. The adsorption mechanisms of iAs on the MNPs are proposed. An Fe-O-As structure was formed on CoFe2O4@MIL-100(Fe) through hydroxyl substitution with the deprotonated iAs species. Monolayer adsorption of As(V) was observed, while hydrogen bonding led to the multi-layer adsorption of neutral As(III) for its high adsorption capacity. The high efficiency and the excellent pH- and interference-tolerance capacities of CoFe2O4@MIL-100(Fe) allowed effective iAs removal from natural water samples, as validated with batch magnetic separation mode and a portable filtration strategy. PMID:28102334

  20. Separation properties of the MIL-125(Ti) Metal-Organic Framework in high-performance liquid chromatography revealing cis/trans selectivity.

    Van der Perre, Stijn; Liekens, Anuschka; Bueken, Bart; De Vos, Dirk E; Baron, Gino V; Denayer, Joeri F M

    2016-10-21

    Monodisperse MIL-125(Ti) Metal-Organic Framework crystals were synthesized and studied as stationary phase in high performance liquid chromatography (HPLC). Different pure compounds and model mixtures (including stereoisomer mixtures) were injected from which chromatographic parameters, including selectivities and resolution factors, were determined to evaluate the adsorption properties and separation performance of MIL-125(Ti) in liquid phase. The MIL-125(Ti) framework displayed a trans selectivity for cis/trans difunctionalized cyclohexane molecules with high selectivity and resolution for 1,3-dimethylcyclohexane and 4-ethylcyclohexanol. The slurry-packed column was further characterized via van Deemter analysis. Fitting of the van Deemter equation through the experimental points allowed to define the contributions of the different processes to plate height with a significant proportion of the A-term, reflecting the importance of a good crystal packing. Although high in comparison to commercial HPLC stationary phases, a very good plate height of around 50μm was found. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Fabrication of γ-Fe2O3 Nanoparticles by Solid-State Thermolysis of a Metal-Organic Framework, MIL-100(Fe, for Heavy Metal Ions Removal

    Shengtao Hei

    2014-01-01

    Full Text Available Porous γ-Fe2O3 nanoparticles were prepared via a solid-state conversion process of a mesoporous iron(III carboxylate crystal, MIL-100(Fe. First, the MIL-100(Fe crystal that served as the template of the metal oxide was synthesized by a low-temperature (<100°C synthesis route. Subsequently, the porous γ-Fe2O3 nanoparticles were fabricated by facile thermolysis of the MIL-100(Fe powders via a two-step calcination treatment. The obtained γ-Fe2O3 was characterized by X-ray diffraction (XRD, N2 adsorption, X-ray photoelectron spectroscopy (XPS, and scanning electron microscopy (SEM techniques, and then used as an adsorbent for heavy metal ions removal in water treatment. This study illustrates that the metal-organic frameworks may be suitable precursors for the fabrication of metal oxides nanomaterials with large specific surface area, and the prepared porous γ-Fe2O3 exhibits a superior adsorption performance for As(V and As(III ions removal in water treatment.

  2. Fe II/Fe III mixed-valence state induced by Li-insertion into the metal-organic-framework Mil53(Fe): A DFT+U study

    Combelles, C.; Ben Yahia, M.; Pedesseau, L.; Doublet, M.-L.

    The iron-based metal-organic-framework MIL53(Fe) has recently been tested as a cathode materials for Li-Ion batteries, leading to promising cycling life and rate capability. Despite a poor capacity of 70 mAh g -1 associated with the exchange of almost 0.5Li/Fe, this result is the first evidence of a reversible lithium insertion never observed in a MOF system. In the present study, the MIL53(Fe) redox mechanism is investigated through first-principles DFT+U calculations. The results show that MIL53(Fe) is a weak antiferromagnetic charge transfer insulator at T = 0 K, with iron ions in the high-spin S = 5/2 state. Its reactivity vs elemental lithium is then investigated as a function of lithium composition and distribution over the most probable Li-sites of the MOF structure. The redox mechanism is fully interpreted as a two-step insertion/conversion mechanism, associated with the stabilization of the Fe 3+/Fe 2+ mixed-valence state prior to the complete decomposition of the inorganic-organic interactions within the porous MOF architecture.

  3. PPy@MIL-100 Nanoparticles as a pH- and Near-IR-Irradiation-Responsive Drug Carrier for Simultaneous Photothermal Therapy and Chemotherapy of Cancer Cells.

    Zhu, Yu-Da; Chen, Su-Ping; Zhao, Huan; Yang, You; Chen, Xiao-Qin; Sun, Jing; Fan, Hong-Song; Zhang, Xing-Dong

    2016-12-21

    A medical nanoplatform with small size, low cost, biocompatibility, good biodegradability, and, in particular, multifunctionality has attracted much attention in the exploration of novel therapeutic methodologies. As an emerging material of self-assembled porous structure, metal-organic frameworks (MOFs) have high expectations because of their special properties compared to traditional porous materials. Therefore, integration of MOFs and functional materials is leading to the creation of new multifunctional composites/hybrids. Photothermal therapy (PTT), using near-IR (NIR) laser-absorbing nanomaterials as PTT agents, has shown encouraging therapeutic effects to photothermally ablate tumors. However, the most of widely used PTT agents are inorganic materials and nonbiodegradable. Herein, uniform polypyrrole (PPy) nanoparticles (NPs) with good biodegradability were synthesized by a microemulsion method. The PPy NPs were further coated with the mesoporous iron-based MOF structure MIL-100 by interaction between PPy NPs and MIL-100 precursors at room temperature. As a multifunctional nanoplatform, an anticancer drug could easily be loaded into the mesopores of the MIL-100 shell. The PPy core, as an organic photothermal agent, is able to photothermally ablate cancer cells and improve the efficacy of chemotherapy under NIR irradiation. The composites showed an outstanding in vivo synergistic anticancer capacity. Our work could encourage further study in the construction of a synergetic system using MOFs and organic PTT agents.

  4. Salen- Zr(IV) complex grafted into amine-tagged MIL-101(Cr) as a robust multifunctional catalyst for biodiesel production and organic transformation reactions

    Hassan, Hassan M. A.; Betiha, Mohamed A.; Mohamed, Shaimaa K.; El-Sharkawy, E. A.; Ahmed, Emad A.

    2017-08-01

    The synthesis of metal-organic frameworks (MOFs), porous coordination polymers with functional groups has received immense interest due to the functional groups can offer desirable properties and allow post-synthetic modification. Herein, for the first time, Zr(IV)-Sal Schiff base complex incorporated into amino-functionalized MIL-101(Cr) framework by salicylaldehyde condensing to amino group, and coordinating Zr(IV) ion have been successfully synthesized. The worthiness of the synthesized material as a catalyst has been examined for the esterification of oleic acid (free fatty acid) with methanol producing biodiesel (methyl oleate), Knoveonagel condensation reaction of aldehydes and Friedel-Crafts acylation of anisole. Our findings demonstrated that Salen-Zr(IV) grafted to framework of NH2-MIL-101(Cr) as a solid acid catalyst exhibited distinct catalytic performance for the production of biodiesel by esterification of oleic acid with methanol, Knoveonagel condensation and Friedel-Crafts acylation. These could be attributed to high surface area which allow high distribution of Zr(IV) species lead to a sufficient contact with the reactants species. Furthermore, the catalyst showed excellent recycling efficiency due to the strong interaction between the Zr(IV) ions and chelating groups in the NH2-MIL-101(Cr)-Sal.

  5. Facile Synthesis of Potassium Poly(heptazine imide) (PHIK)/Ti-Based Metal-Organic Framework (MIL-125-NH2) Composites for Photocatalytic Applications.

    Rodríguez, Nicolás A; Savateev, Aleksandr; Grela, María A; Dontsova, Dariya

    2017-07-12

    Photocatalytically active composites comprising potassium poly(heptazine imide) (PHIK) and a Ti-based metal-organic framework (MOF, MIL-125-NH 2 ) are prepared in situ by simply dispersing both materials in water. The driving forces of composite formation are the electrostatic interactions between the solids and the diffusion of potassium ions from PHIK to MIL-125-NH 2 . This mechanism implies that other composites of poly(heptazine imide) salts and different MOFs bearing positive surface charge can potentially be obtained in a similar fashion. The suggested strategy thus opens a new avenue for the facile synthesis of such materials. The composites are shown to have a superior photocatalytic activity in Rhodamine B degradation under blue light irradiation. The reaction rate is doubled compared to that of pure MOF compound and is 7 times higher than the activity of the pristine PHIK. The results of the electron paramagnetic resonance (EPR) investigations and the analysis of the electronic structures of the solids suggest the electron transfer from MIL-125-NH 2 to PHIK in the composite. The possible pathways for the dye degradation and the rationalization of the increased activity of the composites are elaborated.

  6. Fe3O4 and metal-organic framework MIL-101(Fe) composites catalyze luminol chemiluminescence for sensitively sensing hydrogen peroxide and glucose.

    Qian Tang, Xue; Dan Zhang, Yi; Wei Jiang, Zhong; Mei Wang, Dong; Zhi Huang, Cheng; Fang Li, Yuan

    2018-03-01

    In this work, Fe 3 O 4 and metal-organic framework MIL-101(Fe) composites (Fe 3 O 4 /MIL-101(Fe)) was demonstrated to possess excellent catalytic property to directly catalyze luminol chemiluminescence without extra oxidants. We utilized Fe 3 O 4 /MIL-101(Fe) to develop a ultra-sensitive quantitative analytical method for H 2 O 2 and glucose. The possible mechanism of the chemiluminescence reaction had been investigated. Under optimal conditions, the relative chemiluminescence intensity was linearly proportional to the logarithm of H 2 O 2 concentration in the range of 5-150nM with a limit of detection of 3.7nM (signal-to-noise ratio = 3), and glucose could be linearly detected in the range from 5 to 100nM and the detection limit was 4.9nM (signal-to-noise ratio = 3). Furthermore, the present approach was successfully applied to quantitative determination of H 2 O 2 in medical disinfectant and glucose in human serum samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Composite Monopack for 120mm Mortar, With Plastic Pallet Adapters on a 42" x 53" Wooden Pallet, MIL-STD-1660 Tests, "Design Criteria for Ammunition Unit Loads", and Extreme Temperature Tests

    Dugan, Jeffery L

    2005-01-01

    .... The test units were tested in accordance with the procedures set forth in MIL-STD-1660. Stacking, repetitive shock, edgewise-rotational drop, incline-impact, forklifting, and disassembly testing were conducted on the test units...

  8. Grate Pallet 8232 (GP-8232) Vehicle Pallet, Evaluation Tests MIL-STD-1660, "Design Criteria for Ammunition Unit Loads" and TP-94-01 (REV 1), "Transportability Testing Procedures"

    Barickman, Philip

    2003-01-01

    .... The testing was conducted for informational purposes only. The GP-8232 Vehicle Pallet was evaluated by the testing procedures set forth in MIL-STD-1660 and TP-94-01 (Rev. 1) testing procedures...

  9. Projectile, 155MM, XM982, Excalibur, Packed One (1) per PA179 Container, Unitized Up to Three (3) per 40 in. x 48 in. Wooden Pallet, MIL-STD-1660 Tests

    Dugan, Jeffery L

    2007-01-01

    The U.S. Army Defense Ammunition Center (DAC), Validation Engineering Division (SJMAC-DEV), conducted tests in accordance with MIL-STD-1660, "Design Criteria for Ammunition Unit Loads" on the XM982 155MM Excalibur Projectile packed one...

  10. Investigation of ball bond integrity for 0.8 mil (20 microns) diameter gold bonding wire on low k die in wire bonding technology

    Kudtarkar, Santosh Anil

    Microelectronics technology has been undergoing continuous scaling to accommodate customer driven demand for smaller, faster and cheaper products. This demand has been satisfied by using novel materials, design techniques and processes. This results in challenges for the chip connection technology and also the package technology. The focus of this research endeavor was restricted to wire bond interconnect technology using gold bonding wires. Wire bond technology is often regarded as a simple first level interconnection technique. In reality, however, this is a complex process that requires a thorough understanding of the interactions between the design, material and process variables, and their impact on the reliability of the bond formed during this process. This research endeavor primarily focused on low diameter, 0.8 mil thick (20 mum) diameter gold bonding wire. Within the scope of this research, the integrity of the ball bond formed by 1.0 mil (25 mum) and 0.8 mil (20 mum) diameter wires was compared. This was followed by the evaluation of bonds formed on bond pads having doped SiO2 (low k) as underlying structures. In addition, the effect of varying the percentage of the wire dopant, palladium and bonding process parameters (bonding force, bond time, ultrasonic energy) for 0.8 mil (20 mum) bonding wire was also evaluated. Finally, a degradation empirical model was developed to understand the decrease in the wire strength. This research effort helped to develop a fundamental understanding of the various factors affecting the reliability of a ball bond from a design (low diameter bonding wire), material (low k and bonding wire dopants), and process (wire bonding process parameters) perspective for a first level interconnection technique, namely wire bonding. The significance of this research endeavor was the systematic investigation of the ball bonds formed using 0.8 mil (20 microm) gold bonding wire within the wire bonding arena. This research addressed low k

  11. Sparse Representation Based Multi-Instance Learning for Breast Ultrasound Image Classification

    Lu Bing

    2017-01-01

    Full Text Available We propose a novel method based on sparse representation for breast ultrasound image classification under the framework of multi-instance learning (MIL. After image enhancement and segmentation, concentric circle is used to extract the global and local features for improving the accuracy in diagnosis and prediction. The classification problem of ultrasound image is converted to sparse representation based MIL problem. Each instance of a bag is represented as a sparse linear combination of all basis vectors in the dictionary, and then the bag is represented by one feature vector which is obtained via sparse representations of all instances within the bag. The sparse and MIL problem is further converted to a conventional learning problem that is solved by relevance vector machine (RVM. Results of single classifiers are combined to be used for classification. Experimental results on the breast cancer datasets demonstrate the superiority of the proposed method in terms of classification accuracy as compared with state-of-the-art MIL methods.

  12. The effects of single instance, multiple instance, and general case training on generalized vending machine use by moderately and severely handicapped students.

    Sprague, J R; Horner, R H

    1984-01-01

    This report provides an experimental analysis of generalized vending machine use by six moderately or severely retarded high school students. Dependent variables were training trials to criterion and performance on 10 nontrained "generalization" vending machines. A multiple-baseline design across subjects was used to compare three strategies for teaching generalized vending machine use. Training occurred with (a) a single vending machine, (b) three similar machines, or (c) three machines that...

  13. Two new Bent-toed Geckos of the Cyrtodactylus pulchellus complex from Peninsular Malaysia and multiple instances of convergent adaptation to limestone forest ecosystems.

    Grismer, L Lee; Wood, Perry L; Anuar, Shahrul; Grismer, Marta S; Quah, Evan S H; Murdoch, Matthew L; Muin, Mohd Abdul; Davis, Hayden R; Aguilar, César; Klabacka, Randy; Cobos, Anthony J; Aowphol, Anchalee; Sites, Jack W

    2016-04-25

    A new species of limestone cave-adapted gecko of the Cyrtodactylus pulchellus complex, C. hidupselamanya sp. nov., is described from an isolated karst formation at Felda Chiku 7, Kelantan, Peninsular Malaysia. This formation is scheduled to be completely quarried for its mineral content. From what we know about the life history of C. hidupselamanya sp. nov., this will result in its extinction. A new limestone forest-adapted species, C. lenggongensis sp. nov., from the Lenggong Valley, Perak was previously considered to be conspecific with C. bintangrendah but a re-evaluation of morphological, color pattern, molecular, and habitat preference indicates that it too is a unique lineage worthy of specific recognition. Fortunately C. lenggongensis sp. nov. is not facing extinction because its habitat is protected by the UNESCO Archaeological Heritage of the Lenggong Valley due to the archaeological significance of that region. Both new species can be distinguished from all other species of Cyrtodactylus based on molecular evidence from the mitochondrial gene ND2 and its flanking tRNAs as well as having unique combinations of morphological and color pattern characteristics. Using a time-calibrated BEAST analysis we inferred that the evolution of a limestone habitat preference and its apparently attendant morphological and color pattern adaptations evolved independently at least four times in the C. pulchellus complex between 26.1 and 0.78 mya.

  14. Noble metals can have different effects on photocatalysis over metal-organic frameworks (MOFs): a case study on M/NH₂-MIL-125(Ti) (M=Pt and Au).

    Sun, Dengrong; Liu, Wenjun; Fu, Yanghe; Fang, Zhenxing; Sun, Fangxiang; Fu, Xianzhi; Zhang, Yongfan; Li, Zhaohui

    2014-04-14

    M-doped NH2-MIL-125(Ti) (M=Pt and Au) were prepared by using the wetness impregnation method followed by a treatment with H2 flow. The resultant samples were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS) analyses, N2-sorption BET surface area, and UV/Vis diffuse reflectance spectroscopy (DRS). The photocatalytic reaction carried out in saturated CO2 with triethanolamine (TEOA) as sacrificial agent under visible-light irradiations showed that the noble metal-doping on NH2-MIL-125(Ti) promoted the photocatalytic hydrogen evolution. Unlike that over pure NH2-MIL-125(Ti), in which only formate was produced, both hydrogen and formate were formed over Pt- and Au-loaded NH2-MIL-125(Ti). However, Pt and Au have different effects on the photocatalytic performance for formate production. Compared with pure NH2-MIL-125(Ti), Pt/NH2-MIL-125(Ti) showed an enhanced activity for photocatalytic formate formation, whereas Au has a negative effect on this reaction. To elucidate the origin of the different photocatalytic performance, electron spin resonance (ESR) analyses and density functional theory (DFT) calculations were carried out over M/NH2-MIL-125(Ti).The photocatalytic mechanisms over M/NH2-MIL-125(Ti) (M=Pt and Au) were proposed. For the first time, the hydrogen spillover from the noble metal Pt to the framework of NH2-MIL-125(Ti) and its promoting effect on the photocatalytic CO2 reduction is revealed. The elucidation of the mechanism on the photocatalysis over M/NH2-MIL-125(Ti) can provide some guidance in the development of new photocatalysts based on MOF materials. This study also demonstrates the potential of using noble metal-doped MOFs in photocatalytic reactions involving hydrogen as a reactant, like hydrogenation reactions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Generalized query-based active learning to identify differentially methylated regions in DNA.

    Haque, Md Muksitul; Holder, Lawrence B; Skinner, Michael K; Cook, Diane J

    2013-01-01

    Active learning is a supervised learning technique that reduces the number of examples required for building a successful classifier, because it can choose the data it learns from. This technique holds promise for many biological domains in which classified examples are expensive and time-consuming to obtain. Most traditional active learning methods ask very specific queries to the Oracle (e.g., a human expert) to label an unlabeled example. The example may consist of numerous features, many of which are irrelevant. Removing such features will create a shorter query with only relevant features, and it will be easier for the Oracle to answer. We propose a generalized query-based active learning (GQAL) approach that constructs generalized queries based on multiple instances. By constructing appropriately generalized queries, we can achieve higher accuracy compared to traditional active learning methods. We apply our active learning method to find differentially DNA methylated regions (DMRs). DMRs are DNA locations in the genome that are known to be involved in tissue differentiation, epigenetic regulation, and disease. We also apply our method on 13 other data sets and show that our method is better than another popular active learning technique.

  16. Presentation of a salivary tumour si mil primitive lung with metastases of carcinoid tumour of the colon

    Cataldi, S.; Ximenez; Carzoglio, J.

    2010-01-01

    Introduction: Colon carcinoid tumors are primary tumors in the colon, a rare histology. The lung tumour Si mil - Amyloid is within primary lung tumours, infrequent histology and often behaves like a benign tumour. In this paper we present the case of a patient with a history of having undergone colon surgery for a malignant carcinoid. Two years after developing a lung salivary tumour simile initially presented as metastasis Colonic carcinoid lung tumour. Clinical case: It is about a female patient of 64 years, who in September 2008 he makes a right hemicolectomy extended by an occlusive syndrome sub. Anatomic Pathology (A P) accounted for Carcinoid Tumor Malignant one that committed the entire wall and 50 lymph nodes are resected, all free metastasis. The patient does not receive complementary treatments and an imaging over in December 2009 is evident in a tomographic study a bulky upper lobe pulmonary parenchymal process right. The fiberoptic bronchoscopy (Fob) showed complete obstruction of the right upper lobe bronchus by a vegetating process whose biopsy reported a malignant lung tumor commitment carcinoid support primitive colonic confirmed by immunohistochemistry (IHC). The March 23, 2010 takes place the right upper lobectomy with lymphadenectomy. The A P and IHC study confirmed adenosquamous carcinoma with stroma simile amiloide low degree of malignancy. This injury can be approved to a salivary tumour early lung simile. Bronchial compromised by tumor margin and 22 negative lymph nodes. The patient is referred for additional radiation treatment. Discussion: Tumours of salivary gland type of primitive lung is a very rare condition and diagnosis is a r arity . Usually they originate in the bronchial epithelium submucosal gland. Endo luminal lesions usually occur as infrequently and develop in outlying areas. The development of lung tumours unrelated bronchial structure has been explained by a possible origin from a primitive stem cell that can differentiate a

  17. Remarkable adsorptive removal of nitrogen-containing compounds from a model fuel by a graphene oxide/MIL-101 composite through a combined effect of improved porosity and hydrogen bonding

    Ahmed, Imteaz; Jhung, Sung Hwa, E-mail: sung@knu.ac.kr

    2016-08-15

    Highlights: • Metal-organic frameworks (MIL-101) were composed with graphene oxide (GnO). • GnO/MIL-101 showed the highest adsorption capacity for indole and quinoline. • Adsorption mechanism was clearly shown based on adsorption results and FTIR. • GnO/MIL-101 might be applied commercially considering capacity and reusability. - Abstract: A composite was prepared by combining a highly porous metal-organic framework (MOF), MIL-101 (Cr-benzenedicarboxylate), and graphene oxide (GnO). The porosity of the composite increased appreciably by the addition of GnO up to a specific amount in the MOF, though further increases in the quantity of GnO was detrimental to porosity. The improved porosity of the GnO/MIL-101 composite was utilized for adsorptive denitrogenation (ADN) of a model fuel where indole (IND) and quinoline (QUI) were used as nitrogen-containing compounds (NCCs). It was found that both IND and QUI showed improved adsorption on the composite compared with pristine MIL-101 or GnO due to the improved porosity of the composite. Interestingly, the improvement in adsorption of IND was much higher than the quantity estimated for the porosity. Importantly, GnO/MIL-101 showed the highest adsorption capacities for NCCs. Irrespective of the studied solvents and co-presence of IND and QUI, the composite adsorbent performed ADN most effectively. This remarkable improvement is explained by the additional mechanism of hydrogen bonding between the surface functional groups of GnO and the hydrogen attached to the nitrogen atom of IND. This hydrogen bonding mechanism is also supported by the results of the adsorption of pyrrole and methylpyrrole. On the other hand, QUI does not show hydrogen-bonding capability, and therefore, its enhanced adsorption originates from only the increased porosity of the adsorbents.

  18. Remarkable adsorptive removal of nitrogen-containing compounds from a model fuel by a graphene oxide/MIL-101 composite through a combined effect of improved porosity and hydrogen bonding

    Ahmed, Imteaz; Jhung, Sung Hwa

    2016-01-01

    Highlights: • Metal-organic frameworks (MIL-101) were composed with graphene oxide (GnO). • GnO/MIL-101 showed the highest adsorption capacity for indole and quinoline. • Adsorption mechanism was clearly shown based on adsorption results and FTIR. • GnO/MIL-101 might be applied commercially considering capacity and reusability. - Abstract: A composite was prepared by combining a highly porous metal-organic framework (MOF), MIL-101 (Cr-benzenedicarboxylate), and graphene oxide (GnO). The porosity of the composite increased appreciably by the addition of GnO up to a specific amount in the MOF, though further increases in the quantity of GnO was detrimental to porosity. The improved porosity of the GnO/MIL-101 composite was utilized for adsorptive denitrogenation (ADN) of a model fuel where indole (IND) and quinoline (QUI) were used as nitrogen-containing compounds (NCCs). It was found that both IND and QUI showed improved adsorption on the composite compared with pristine MIL-101 or GnO due to the improved porosity of the composite. Interestingly, the improvement in adsorption of IND was much higher than the quantity estimated for the porosity. Importantly, GnO/MIL-101 showed the highest adsorption capacities for NCCs. Irrespective of the studied solvents and co-presence of IND and QUI, the composite adsorbent performed ADN most effectively. This remarkable improvement is explained by the additional mechanism of hydrogen bonding between the surface functional groups of GnO and the hydrogen attached to the nitrogen atom of IND. This hydrogen bonding mechanism is also supported by the results of the adsorption of pyrrole and methylpyrrole. On the other hand, QUI does not show hydrogen-bonding capability, and therefore, its enhanced adsorption originates from only the increased porosity of the adsorbents.

  19. Polydimethylsiloxane/MIL-100(Fe) coated stir bar sorptive extraction-high performance liquid chromatography for the determination of triazines in environmental water samples.

    Lei, Yun; Chen, Beibei; You, Linna; He, Man; Hu, Bin

    2017-12-01

    Polydimethylsiloxane (PDMS)/MIL-100(Fe) coated stir bar was prepared by sol gel technique, and good preparation reproducibility was achieved with relative standard deviations (RSDs) ranging from 2.6% to 7.5% (n=7) and 3.6% to 10.8% (n=7) for bar-to-bar and batch-to-batch, respectively. Compared with commercial PDMS coated stir bar (Gerstel) and PEG coated stir bar (Gerstel), the prepared PDMS/MIL-100(Fe) stir bar showed better extraction efficiency for target triazines compounds. It also exhibited relatively fast extraction/desorption kinetics and long lifespan. Based on it, a method of PDMS/MIL-100(Fe) coated stir bar sorptive extraction (SBSE)-high performance liquid chromatography-ultraviolet detector (HPLC-UV) was developed for the determination of six triazines (simazine, atrazine, prometon, ametryn, prometryne and prebane) in environmental water samples. Several parameters affecting SBSE of six target triazines including extraction time, stirring rate, sample pH, ionic strength, desorption solvent and desorption time were investigated. Under the optimal experimental conditions, the limits of detection (LODs, S/N=3) were found to be in the range of 0.021-0.079μgL -1 . The repeatability RSDs were in the range of 2.3-6.3% (n=7, c=0.5μgL -1 ) and the enrichment factors (EFs) ranged from 51.1 to 102-fold (theoretical EF was 200-fold). The proposed method was applied to the analysis of target triazines in environmental water samples, with recoveries of 98.0-118% and 94.0-107% for spiked East Lake water and local pond water samples, respectively. Copyright © 2017. Published by Elsevier B.V.

  20. Low-temperature binding of NO adsorbed on MIL-100(Al)-A case study for the application of high resolution pulsed EPR methods and DFT calculations.

    Mendt, Matthias; Barth, Benjamin; Hartmann, Martin; Pöppl, Andreas

    2017-12-14

    The low-temperature binding of nitric oxide (NO) in the metal-organic framework MIL-100(Al) has been investigated by pulsed electron nuclear double resonance and hyperfine sublevel correlation spectroscopy. Three NO adsorption species have been identified. Among them, one species has been verified experimentally to bind directly to an 27 Al atom and all its relevant 14 N and 27 Al hyperfine interaction parameters have been determined spectroscopically. Those parameters fit well to the calculated ones of a theoretical cluster model, which was derived by density functional theory (DFT) in the present work and describes the low temperature binding of NO to the regular coordinatively unsaturated Al 3+ site of the MIL-100(Al) structure. As a result, the Lewis acidity of that site has been characterized using the NO molecule as an electron paramagnetic resonance active probe. The DFT derived wave function analysis revealed a bent end-on coordination of the NO molecule adsorbed at that site which is almost purely ionic and has a weak binding energy. The calculated flat potential energy surface of this species indicates the ability of the NO molecule to freely rotate at intermediate temperatures while it is still binding to the Al 3+ site. For the other two NO adsorption species, no structural models could be derived, but one of them is indicated to be adsorbed at the organic part of the metal-organic framework. Hyperfine interactions with protons, weakly coupled to the observed NO adsorption species, have also been measured by pulsed electron paramagnetic resonance and found to be consistent with their attribution to protons of the MIL-100(Al) benzenetricarboxylate ligand molecules.

  1. Synthesis of iron-based metal-organic framework MIL-53 as an efficient catalyst to activate persulfate for the degradation of Orange G in aqueous solution.

    Pu, Mengjie; Guan, Zeyu; Ma, Yongwen; Wan, Jinquan; Wang, Yan; Brusseau, Mark L; Chi, Haiyuan

    2018-01-05

    A series of MIL-53(Fe) materials were synthesized using a solvothermal method under different temperature and time conditions and were used as catalysts to activate persulfate and degrade Orange G (OG). Influences of the above conditions on the crystal structure and catalytic behavior were investigated. Degradation of OG under different conditions was evaluated, and the possible activation mechanism was speculated. The results indicate that high synthesis temperature (larger than 170 °C) leads to poor crystallinity and low catalytic activity, while MIL-53(Fe) cannot fully develop at low temperature (100 or 120 °C). The extension of synthesis time from 5 h to 3 d can increase the crystallinity of the samples, but weakened the catalytic activity, which was caused by the reduction of BET surface area and the amount of Fe (II)-coordinative unsaturated sites. Among all the samples, MIL-53(Fe)-A possesses the best crystal structure and catalytic activity. In optimal conditions, OG can be totally decolorized after degradation for 90 min, and a removal rate of 74% for COD was attained after 120 min. The initial solution pH had great influence on OG degradation, with the greatest removal in acidic pH environment. ESR spectra showed that sulfate radical (SO 4 - ·), hydroxyl radical (OH·), persulfate radical (S 2 O 8 - ·), and superoxide radical (O 2 ·) exist in this system under acidic conditions. Furthermore, with the increase of pH, the relative amount of O 2 · increases while that of OH· and SO 4 - · decreases, resulting in a reduced oxidizing capacity of the system.

  2. Low-temperature binding of NO adsorbed on MIL-100(Al)—A case study for the application of high resolution pulsed EPR methods and DFT calculations

    Mendt, Matthias; Barth, Benjamin; Hartmann, Martin; Pöppl, Andreas

    2017-12-01

    The low-temperature binding of nitric oxide (NO) in the metal-organic framework MIL-100(Al) has been investigated by pulsed electron nuclear double resonance and hyperfine sublevel correlation spectroscopy. Three NO adsorption species have been identified. Among them, one species has been verified experimentally to bind directly to an 27Al atom and all its relevant 14N and 27Al hyperfine interaction parameters have been determined spectroscopically. Those parameters fit well to the calculated ones of a theoretical cluster model, which was derived by density functional theory (DFT) in the present work and describes the low temperature binding of NO to the regular coordinatively unsaturated Al3+ site of the MIL-100(Al) structure. As a result, the Lewis acidity of that site has been characterized using the NO molecule as an electron paramagnetic resonance active probe. The DFT derived wave function analysis revealed a bent end-on coordination of the NO molecule adsorbed at that site which is almost purely ionic and has a weak binding energy. The calculated flat potential energy surface of this species indicates the ability of the NO molecule to freely rotate at intermediate temperatures while it is still binding to the Al3+ site. For the other two NO adsorption species, no structural models could be derived, but one of them is indicated to be adsorbed at the organic part of the metal-organic framework. Hyperfine interactions with protons, weakly coupled to the observed NO adsorption species, have also been measured by pulsed electron paramagnetic resonance and found to be consistent with their attribution to protons of the MIL-100(Al) benzenetricarboxylate ligand molecules.

  3. A real time data acquisition system using the MIL-STD-1553B bus. [for transmission of data to host computer for control law processing

    Peri, Frank, Jr.

    1992-01-01

    A flight digital data acquisition system that uses the MIL-STD-1553B bus for transmission of data to a host computer for control law processing is described. The instrument, the Remote Interface Unit (RIU), can accommodate up to 16 input channels and eight output channels. The RIU employs a digital signal processor to perform local digital filtering before sending data to the host. The system allows flexible sensor and actuator data organization to facilitate quick control law computations on the host computer. The instrument can also run simple control laws autonomously without host intervention. The RIU and host computer together have replaced a similar larger, ground minicomputer system with favorable results.

  4. Fabrication, interfacial characterization and mechanical properties of continuous Al{sub 2}O{sub 3} ceramic fiber reinforced Ti/Al{sub 3}Ti metal-intermetallic laminated (CCFR-MIL) composite

    Han, Yuqiang; Lin, Chunfa; Han, Xiaoxiao; Chang, Yunpeng; Guo, Chunhuan, E-mail: guochunhuan@hrbeu.edu.cn; Jiang, Fengchun, E-mail: fengchunjiang@hrbeu.edu.cn

    2017-03-14

    Continuous Al{sub 2}O{sub 3} ceramic fiber reinforced Ti/Al{sub 3}Ti metal-intermetallic laminated (CCFR-MIL) composite was fabricated using a vacuum hot pressing (VHP) sintering method and followed by hot isostatic pressing (HIP). The microstructure characteristics of the interfaces between Ti and Al{sub 3}Ti, as well as Al{sub 2}O{sub 3} fiber and Al{sub 3}Ti intermetallic were analyzed by scanning electron microscopy (SEM). Elemental distribution in the interfacial reaction zones were quantitatively examined by energy-dispersive spectroscopy (EDS). The phases in the composite were identified by X-ray diffractometer (XRD). The mechanical properties of the CCFR-MIL composite were measured using compression and tensile tests under quasi-static strain rate. The experimental results indicated that the residual Al was found in Al{sub 3}Ti intermetallic layer of CCFR-MIL composite. The interfacial reactions occurred during HIP and the reaction products were determined to be Al{sub 2}Ti, TiSi{sub 2}, TiO{sub 2} and Al{sub 2}SiO{sub 5} phases. Compared to Ti/Al{sub 3}Ti MIL composite without fiber reinforcement, both the strength and failure strain of CCFR-MIL composite under both compressive and tensile stress states increased due to the contribution of the continuous ceramic Al{sub 2}O{sub 3} fiber.

  5. La universidad de lãs mil y una noches. The University of a Thousand and One Nights

    Luis Porter

    2005-05-01

    Full Text Available Se trata de un artículo que surge de una pregunta hipotética, aunque indudablemente realista, formulada por un profesor universitario mientras transita rumbo a su institución: ¿Qué es mi universidad? ¿Qué me hace pasar de la decepción al entusiasmo, para volver después al sinsabor y remontar más tarde la alegría? Las respuestas dan lugar a un diálogo interior, durante el que se toma conciencia de que la educación trasciende las puertas y ventanas del aula, para llegar a aquellos lugares lejanos que Juvenal definía como "ultra Auroram et Gangem", ("más allá de la Aurora y el Ganges", y que nosotros, los latinoamericanos, podríamos llamar: "ultra Tropicus et Amazonam". En suma, en su diálogo interior el académico toma conciencia de que su labor educativa abarca un territorio mayor al constreñido a la geografía específica de un sitio o de una institución. De esta manera nos ayuda a asumir que en el ámbito de la educación existen varios atributos que debemos contribuir a crear o recrear: la esperanza, la oportunidad, la imaginación. También a entender que al dedicarnos a ejercer nuestra capacidad de re-lacionar, re-latar, referir y re-flexionar, organizamos, discurrimos, transferimos, construyendo nuestra narrativa, es decir la capacidad de urdir en cada jornada un nuevo plan. Planear cada día, será entonces, como Sherezada, tejer un nuevo cuento, necesario para poder seguir actuando, puesto que la palabra es el único hilo que le da sentido a nuestra condición de educadores, a nuestro ser universitario. This article uses the title of the famous book Arabian Nights which in Spanish (Las mil y una noches has a time connotation, similar to "for ever and a day" in English. In Spanish, "thousand" is a way to mean "infinite"; if you add one to infinite then you have numberless nights. The article departs from a hypothetical question an academic asks him/herself in his way to the educational institution where he-she works

  6. Exsolution of Iron-Titanium Oxides in Magnetite in Miller Range (MIL) 03346 Nakhlite: Evidence for Post Crystallization Reduction in the Nakhlite Cumulate Pile

    Righter, Kevin; Keller, L. P.; Rahman, Z.; Christoffersen, R.

    2012-01-01

    MIL 03346 is one of the most mesostasis-rich nakhlites [1] and thought to have equilibrated at oxygen fugacities near the fayalite-magnetite-quartz oxygen (FMQ) buffer ([2,3]). Studies of FeTi oxides in nakhlites have led to additional constraints on their equilibration temperatures and fO2s [4,5,6,7]. Comparison of these results to fO2s calculated for shergottites indicates that nakhlites are among the most oxidized samples from the martian meteorite suite [2]. The mesostasis of MIL 03346 contains skeletal titanomagnetite. Several scientists noticed several years ago (e.g. [8]) that this titanomagnetite contains very fine oxidation-driven exsolution lamellae (Figure 1). However, the lamellae are so small that they cannot be characterized by electron microprobe analysis (EMPA). Here we select several areas for focused ion beam (FIB) extraction, prepare transmission electron microscopy (TEM) foils, and identify and analyze the lamellae using TEM at the Johnson Space Center (JSC). The resulting analyses are combined with previous work on nakhlites to interpret the thermal and oxidation history of this meteorite group.

  7. Estudios previos para la restauración de la azotea de la Casa Milá de Barcelona (Cataluña, España

    Lacuesta Contreras, Raquel

    1993-12-01

    Full Text Available The Casa Milá of Barcelona, work of the architect Antoni Gaudí, built between 1906 and 1911, was purchased in by the Caixa de Catalunya which then started a process of restoration of the building. One of the stages of this intervention will consist of restoring the roof with all the architectural sculptural elements it contains (the staircase boxes, chimneys, ventilation towers and perimetral paths. A number of previous studies have been done to this end. They deal with the historical constructive, documentary and artistic aspects of all these elements as well as with an action proposal to be taken into account in the restoration project.

    La Casa Milá de Barcelona, obra del arquitecto Antoni Gaudí construida entre 1906 y 1911, fue adquirida en 1986 por la Caixa de Catalunya que a partir de entonces inició un proceso de restauración del edificio. Una de las fases de la intervención consistirá en restaurar la azotea con todos los elementos arquitectónicos-escultóricos que contiene (cajas de escalera, chimeneas, torres de ventilación y pasos de ronda. A tal fin, se han realizado unos estudios previos que contemplan los aspectos histórico-constructivos, documental y artístico de todos estos elementos, y también una propuesta de actuación a tener en cuenta en el proyecto de restauración.

  8. Magnetic solid-phase extraction of triazine herbicides from rice using metal-organic framework MIL-101(Cr) functionalized magnetic particles.

    Liang, Li; Wang, Xinghua; Sun, Ying; Ma, Pinyi; Li, Xinpei; Piao, Huilan; Jiang, Yanxiao; Song, Daqian

    2018-03-01

    The metal-organic framework (MOF) functionalized magnetic graphene oxide/mesoporous silica composites (Fe 3 O 4 @SiO 2 -GO/MIL-101(Cr)) were synthesized and utilized as magnetic solid-phase extraction (MSPE) adsorbent for the extraction of seven triazine herbicides (terbuthylazine, secbumeton, terbumeton, atraton, atrazine, prometon and trietazine) in rice samples. Several experimental parameters, including type and volume of extraction solvent, amount of MIL-101(Cr), extraction time, volume of desorption solvent and desorption time were investigated and optimized. The limits of detection (LODs) of seven triazine herbicides obtained by using the proposed MSPE method combined with high performance liquid chromatography (HPLC) were in the range of 0.010-0.080µgkg -1 . The recoveries of the triazine herbicides in spiked rice samples ranged from of 83.9-103.5% with the relative standard deviations lower than 8.7%. The intra and inter-day (n = 6) precisions for all triazine herbicides at the spiked level of 100.0µgkg -1 were 1.4-5.9% and 2.6-7.8%, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Elucidating the Vibrational Fingerprint of the Flexible Metal–Organic Framework MIL-53(Al) Using a Combined Experimental/Computational Approach

    2018-01-01

    In this work, mid-infrared (mid-IR), far-IR, and Raman spectra are presented for the distinct (meta)stable phases of the flexible metal–organic framework MIL-53(Al). Static density functional theory (DFT) simulations are performed, allowing for the identification of all IR-active modes, which is unprecedented in the low-frequency region. A unique vibrational fingerprint is revealed, resulting from aluminum-oxide backbone stretching modes, which can be used to clearly distinguish the IR spectra of the closed- and large-pore phases. Furthermore, molecular dynamics simulations based on a DFT description of the potential energy surface enable determination of the theoretical Raman spectrum of the closed- and large-pore phases for the first time. An excellent correspondence between theory and experiment is observed. Both the low-frequency IR and Raman spectra show major differences in vibrational modes between the closed- and large-pore phases, indicating changes in lattice dynamics between the two structures. In addition, several collective modes related to the breathing mechanism in MIL-53(Al) are identified. In particular, we rationalize the importance of the trampoline-like motion of the linker for the phase transition. PMID:29449906

  10. Application of novel metal organic framework, MIL-53(Fe) and its magnetic hybrid: For removal of pharmaceutical pollutant, doxycycline from aqueous solutions.

    Naeimi, Shakiba; Faghihian, Hossein

    2017-07-01

    As a pharmaceutical pollutant, doxycycline causes contamination when enters into the environment. In this research MIL-53(Fe), and its magnetic hybrid MIL-53(Fe)/Fe 3 O 4 were synthesized and employed for removal of doxycycline from aqueous solutions. The adsorbents were characterized by XRD, SEM, BET, FTIR, EDAX, VSM and TG-DTG technique. The effect of different variables such as DOC concentration, pH, contacting time, and adsorbent dose on the removal efficiency was studied and under optimized conditions the adsorption capacity of 322mgg -1 was obtained. The adsorption process was kinetically fast and the equilibration was attained within 30min. The used adsorbent was easily separated from the solution by applying external magnetic field. The regenerated adsorbent retained most of its initial capacity after six regeneration steps. The effect of ionic strength was studied and it was indicated that removal of doxycycline from salt-containing water with moderate ionic strengths was quite feasible. Langmuir, Freundlich, Tempkin and Dubinin-Redushkevich isotherms were employed to describe the nature of adsorption process. The sorption data was well interpreted by the Longmuir model. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Co-Labeling for Multi-View Weakly Labeled Learning.

    Xu, Xinxing; Li, Wen; Xu, Dong; Tsang, Ivor W

    2016-06-01

    It is often expensive and time consuming to collect labeled training samples in many real-world applications. To reduce human effort on annotating training samples, many machine learning techniques (e.g., semi-supervised learning (SSL), multi-instance learning (MIL), etc.) have been studied to exploit weakly labeled training samples. Meanwhile, when the training data is represented with multiple types of features, many multi-view learning methods have shown that classifiers trained on different views can help each other to better utilize the unlabeled training samples for the SSL task. In this paper, we study a new learning problem called multi-view weakly labeled learning, in which we aim to develop a unified approach to learn robust classifiers by effectively utilizing different types of weakly labeled multi-view data from a broad range of tasks including SSL, MIL and relative outlier detection (ROD). We propose an effective approach called co-labeling to solve the multi-view weakly labeled learning problem. Specifically, we model the learning problem on each view as a weakly labeled learning problem, which aims to learn an optimal classifier from a set of pseudo-label vectors generated by using the classifiers trained from other views. Unlike traditional co-training approaches using a single pseudo-label vector for training each classifier, our co-labeling approach explores different strategies to utilize the predictions from different views, biases and iterations for generating the pseudo-label vectors, making our approach more robust for real-world applications. Moreover, to further improve the weakly labeled learning on each view, we also exploit the inherent group structure in the pseudo-label vectors generated from different strategies, which leads to a new multi-layer multiple kernel learning problem. Promising results for text-based image retrieval on the NUS-WIDE dataset as well as news classification and text categorization on several real-world multi

  12. Correlation of Gas Permeability in a Metal-Organic Framework MIL-101(Cr)-Polysulfone Mixed-Matrix Membrane with Free Volume Measurements by Positron Annihilation Lifetime Spectroscopy (PALS).

    Jeazet, Harold B Tanh; Koschine, Tönjes; Staudt, Claudia; Raetzke, Klaus; Janiak, Christoph

    2013-10-25

    Hydrothermally stable particles of the metal-organic framework MIL-101(Cr) were incorporated into a polysulfone (PSF) matrix to produce mixed-matrix or composite membranes with excellent dispersion of MIL-101 particles and good adhesion within the polymer matrix. Pure gas (O2, N2, CO2 and CH4) permeation tests showed a significant increase of gas permeabilities of the mixed-matrix membranes without any loss in selectivity. Positron annihilation lifetime spectroscopy (PALS) indicated that the increased gas permeability is due to the free volume in the PSF polymer and the added large free volume inside the MIL-101 particles. The trend of the gas transport properties of the composite membranes could be reproduced by a Maxwell model.

  13. Correlation of Gas Permeability in a Metal-Organic Framework MIL-101(Cr)–Polysulfone Mixed-Matrix Membrane with Free Volume Measurements by Positron Annihilation Lifetime Spectroscopy (PALS)

    Jeazet, Harold B. Tanh; Koschine, Tönjes; Staudt, Claudia; Raetzke, Klaus; Janiak, Christoph

    2013-01-01

    Hydrothermally stable particles of the metal-organic framework MIL-101(Cr) were incorporated into a polysulfone (PSF) matrix to produce mixed-matrix or composite membranes with excellent dispersion of MIL-101 particles and good adhesion within the polymer matrix. Pure gas (O2, N2, CO2 and CH4) permeation tests showed a significant increase of gas permeabilities of the mixed-matrix membranes without any loss in selectivity. Positron annihilation lifetime spectroscopy (PALS) indicated that the increased gas permeability is due to the free volume in the PSF polymer and the added large free volume inside the MIL-101 particles. The trend of the gas transport properties of the composite membranes could be reproduced by a Maxwell model. PMID:24957061

  14. A Novel Classification Method for Syndrome Differentiation of Patients with AIDS

    Yufeng Zhao

    2015-01-01

    Full Text Available We consider the analysis of an AIDS dataset where each patient is characterized by a list of symptoms and is labeled with one or more TCM syndromes. The task is to build a classifier that maps symptoms to TCM syndromes. We use the minimum reference set-based multiple instance learning (MRS-MIL method. The method identifies a list of representative symptoms for each syndrome and builds a Gaussian mixture model based on them. The models for all syndromes are then used for classification via Bayes rule. By relying on a subset of key symptoms for classification, MRS-MIL can produce reliable and high quality classification rules even on datasets with small sample size. On the AIDS dataset, it achieves average precision and recall 0.7736 and 0.7111, respectively. Those are superior to results achieved by alternative methods.

  15. Metal-organic framework MIL-101(Cr) as a sorbent of porous membrane-protected micro-solid-phase extraction for the analysis of six phthalate esters from drinking water: a combination of experimental and computational study.

    Wang, Ting; Wang, Jian; Zhang, Conglu; Yang, Zhao; Dai, Xinpeng; Cheng, Maosheng; Hou, Xiaohong

    2015-08-07

    An attractive metal-organic framework (MOF) MIL-101(Cr) material was synthesized at the nanoscale and applied as a sorbent in the porous membrane-protected micro-solid-phase extraction (μ-SPE) device for the pre-concentration of phthalate esters (PAEs) in drinking water samples for the first time. Parameters influencing the extraction efficiency, such as the selection of sorbent materials, pH adjustment, the effect of salt, magnetic-stirring extraction time, the desorption solvent and the desorption time, were investigated. Under the optimum conditions, the limits of detection from gas chromatography-mass spectrometric analysis for PAEs varied from 0.004 to 0.02 μg L(-1). The linear ranges were from 0.1 to 50 μg L(-1) or from 0.2 to 50 μg L(-1) for the analytes with the relative standard deviations fluctuating from 0.8 to 10.9% (n = 5). The enrichment factors (EFs) for the target PAEs were varied from 143 to 187. MIL-101(Cr) exhibited remarkable advantages compared to activated carbon and MIL-100(Fe). On the other hand, the computational method was first used to predict the adsorption of MIL-101(Cr) towards PAEs. The molecular interactions and the free binding energies between MIL-101(Cr) and PAEs were observed and calculated in terms of the molecular modeling method. MIL-101(Cr) showed high potential in the analysis of PAEs at trace levels in drinking water. The computational result was consistent with the detected enrichment factors. The computational modeling accurately predicted the extraction efficiency of MOF-based material towards the target analytes. Therefore, the combination of experimental and computational study provided a new strategy on the trace contaminant analysis.

  16. A novel metal-organic framework composite MIL-101(Cr)@GO as an efficient sorbent in dispersive micro-solid phase extraction coupling with UHPLC-MS/MS for the determination of sulfonamides in milk samples.

    Jia, Xiuna; Zhao, Pan; Ye, Xiu; Zhang, Lianjun; Wang, Ting; Chen, Qinyu; Hou, Xiaohong

    2017-07-01

    As a novel material, metal-organic framework/graphite oxide (MIL-101(Cr)@GO) has great potential for the pretreatment of trace analytes. In the present study, MIL-101(Cr)@GO was synthesized using a solvothermal synthesis method at the nanoscale and was applied as sorbent in the dispersive micro-solid phase extraction (DMSPE) for the enrichment of the trace sulfonamides (SAs) from milk samples for the first time. Several experimental parameters including kinds of sorbents, the effect of pH, the amount of MIL-101(Cr)@GO, ionic strength, adsorption time, desorption solvent and desorption time were investigated. Under the optimal conditions, the linear ranges were from 0.1 to 10μg/L, 0.2-20μg/L or 0.5-50μg/L for the analytes with regression coefficients (r) from 0.9942 to 0.9999. The limits of detection were between 0.012 and 0.145μg/L. The recoveries ranged from 79.83% to 103.8% with relative standard deviations (RSDs)MIL-101(Cr)@GO exhibited remarkable advantages compared to MIL-101(Cr), MIL-100(Fe), activated carbon and other sorbent materials used in pretreatment methods. A simple, rapid, sensitive, inexpensive and less solvent consuming method of DMSPE-ultra-high performance liquid chromatography-tandem mass spectrometry (DMSPE-UHPLC-MS/MS) was successfully applied to the pre-concentration and determination of twelve SAs in milk samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Application of Fe3O4@MIL-100 (Fe) core-shell magnetic microspheres for evaluating the sorption of organophosphate esters to dissolved organic matter (DOM).

    Pang, Long; Yang, Peijie; Yang, Huiqiang; Ge, Liming; Xiao, Jingwen; Zhou, Yifan

    2018-06-01

    Organophosphate esters (OPEs) are widely used as flame retardants and plasticizers in many products and materials. Because of the potential biologic toxicity on human beings, OPEs are regarded as a class of emerging pollutants. Dissolved organic matters (DOM) have significant effects on the bioavailability and toxicity of the pollutants in the environment. Negligible-depletion solid-phase microextraction (nd-SPME) is an efficient way for measuring the freely dissolved pollutants but suffers from long equilibrium time. Metal-organic frameworks (MOFs) are a class of porous crystalline materials with unique properties such as high pore volume, regular porosity, and tunable pore size, being widely used for the extraction of various organic compounds. Here we developed a novel method for quick determination the sorption coefficients of OPEs to DOM in aquatic phase using Fe 3 O 4 @MIL-100 (Fe) core-shell magnetic microspheres. The mesoporous structures of the as-synthesized microspheres hindered the extraction of OPEs which associated with humic acid due to the volume exclusion effect. However, the freely dissolved OPEs can access into the mesoporous and then were extracted by MIL-100 (Fe). Due to the small pore size (4.81 nm), large surface area (141 m 2  g -1 ), high pore volume (0.17 g 3  g -1 ), and ultra-thin MOFs layers, Fe 3 O 4 @MIL-100 (Fe) core-shell magnetic microspheres have large contact area for the analytes in aqueous phase and therefore the diffusion distance was largely shortened. Besides, the microspheres can be collected conveniently after the extraction process by applying a magnetic field. Compared to the nd-SPME method with 35 h equilibration time (t 90% ), the proposed method for these studied OPEs only need 24 min to achieve equilibration. The sorption coefficients (logK DOC ) of the OPEs to humic acid were ranged from 3.84-5.28, which were highly consistent with the results by using polyacrylate-coated fiber and polydimethylsiloxane

  18. Comentario al libro "Los mil abrazos de Morfeo" de la Académica Eugenia Guzmán Cervantes

    Adolfo de Francisco Zea

    2002-04-01

    Full Text Available

    Señor Presidente, Señores Académicos:


    Permítame, Señor Presidente, expresar a Usted y a la Junta Directiva de la Academia Nacional de Medicina mi profundo agradecimiento por la distinción de que he sido objeto al designárseme para hacer el comentario de orden al libro «Los Mil Abrazos de Morfeo», del que es autora la distinguida Académica y Profesora Titular del Departamento de Psicología de la Universidad Nacional, doña Eugenia Guzmán Cervantes, quien esta noche lo ha presentado con brillantez, erudición y amenidad ante los señores Académicos y el distinguido Auditorio que nos acompaña.

    La obra es el resultado de largos años de estudio y de trabajo de su autora en los campos de la neuropsicología clínica, la neurofisiología del sueño y sus diferentes patologías, la psicopatología de la conducta y los aspectos biológicos del comportamiento, y de su interés por incursionar en el área de los ritmos biológicos y sus implicaciones en la industria y el transporte aéreo, para compensar, según confiesa, su frustración al no haber podido ser piloto de pruebas.

    Esta ambición de Eugenia, frustrada en buena hora, le ha permitido llegar a alturas aún mayores que las que hubiera podido alcanzar como aviadora, al entregar a la comunidad científica este espléndido libro de casi trescientas páginas, treinta de las cuales corresponden a referencias bibliográficas, en las que actualiza los conocimientos que se tienen sobre el dormir y el soñar, discute con autoridad las diversas teorías formuladas sobre estas materias, analiza con propiedad los datos aportados por la ciencia en los últimos años y expone además, sus personales y bien sedimentadas opiniones sobre tan fascinantes temas.

    Por tratarse de asuntos que han inquietado a la humanidad desde tiempo inmemorial, es lógico que la autora se refiera a tres dioses de la mitología griega: Morfeo, el dios

  19. Experimental screening of porous materials for high pressure gas adsorption and evaluation in gas separations: application to MOFs (MIL-100 and CAU-10).

    Wiersum, Andrew D; Giovannangeli, Christophe; Vincent, Dominique; Bloch, Emily; Reinsch, Helge; Stock, Norbert; Lee, Ji Sun; Chang, Jong-San; Llewellyn, Philip L

    2013-02-11

    A high-throughput gas adsorption apparatus is presented for the evaluation of adsorbents of interest in gas storage and separation applications. This instrument is capable of measuring complete adsorption isotherms up to 40 bar on six samples in parallel using as little as 60 mg of material. Multiple adsorption cycles can be carried out and four gases can be used sequentially, giving as many as 24 adsorption isotherms in 24 h. The apparatus has been used to investigate the effect of metal center (MIL-100) and functional groups (CAU-10) on the adsorption of N(2), CO(2), and light hydrocarbons on MOFs. This demonstrates how it can serve to evaluate sample quality and adsorption reversibility, to determine optimum activation conditions and to estimate separation properties. As such it is a useful tool for the screening of novel adsorbents for different applications in gas separation, providing significant time savings in identifying potentially interesting materials.

  20. Development of 30-pin connectors for electronic modules of C and I systems for NPP's confirming to customized MIL STD-1344 requirements

    Marathe, P.P.; Madala, Kalyan C.; Ramakrishna, P.

    2014-01-01

    The electrical connectors form an important constituent of C and I system where customized circuits and hardware is required to be configured meeting the Nuclear Power Plant regulatory requirements. C and I hardware has to handle multiple hundreds of I/O's and the system architectures are made in modular construction having C and I system hardware packaged in plug-in electronic modules in the required form factors. In addition if the system has to satisfy customized JSS 55555 requirements meeting stringent shock, vibration and environmental specifications, the connectors used for the electronic modules shall meet the customized MIL STD-1344 requirements and meet reliability target for the system. 30-pin type special connectors for electronic modules and 2x30 (60) pin field cabling connectors were developed meeting the required qualification specifications. (author)

  1. Identificada una malformació dental no gaire comuna en un individu del III mil·lenni aC

    López Onaindia, Diego

    2016-01-01

    Un estudi de la UAB ha permès identificar el cas més antic de macrodòncia bilateral aïllada a les segones premolars inferiors descrit fins a la data. Es tracta d'una malformació dental no gaire comuna que s'ha trobat en un individu de la Cova del Pantà de Foix (Castellet i la Gornal, Barcelona), les inhumacions de la qual estan datades al III mil·lenni aC. Tot i que no es coneix la causa d'aquesta malformació, els resultats la relacionen amb l'existència de factors d'estrès ambiental que haur...

  2. Synthesis of highly efficient Mn{sub 2}O{sub 3} catalysts for CO oxidation derived from Mn-MIL-100

    Zhang, Xiaodong, E-mail: fatzhxd@126.com [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093 (China); Li, Hongxin; Hou, Fulin; Yang, Yang; Dong, Han; Liu, Ning [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093 (China); Wang, Yuxin [Institute of Applied Biotechnology, Taizhou Vocation & Technical College, Taizhou, Zhejiang 318000 (China); Cui, Lifeng, E-mail: lifeng.cui@gmail.com [Environment and Low-Carbon Research Center, School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200093 (China)

    2017-07-31

    Highlights: • The morphology of porous Mn{sub 2}O{sub 3} cubes was inherited from Mn-MIL-100 template. • Mn{sub 2}O{sub 3} obtained at calcined temperature of 700 °C displayed high activity. • Enhanced activity is attributed to surface active oxygen, and reduction behavior. - Abstract: In this work, metal-organic frameworks (MOFs) Mn-MIL-100 were first prepared, which were next used as templates to obtain the irregular porous Mn{sub 2}O{sub 3} cubes through calcination with air at different temperature. The catalysts were characterized by N{sub 2} adsorption-desorption, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), H{sub 2}-temperature program reduction (H{sub 2}-TPR) and X-ray photoelectron spectroscopic (XPS). The catalytic activity for CO oxidation over Mn{sub 2}O{sub 3} catalysts was investigated. It was found that calcination temperature had a strong effect on the structure and catalytic activity of Mn{sub 2}O{sub 3} catalyst. Mn{sub 2}O{sub 3} catalyst obtained by calcined at 700 °C (Mn{sub 2}O{sub 3}-700) showed a smaller specific surface area, but displayed a high catalytic activity and excellent stability with a complete CO conversion temperature (T{sub 98}) of 240 °C, which was attributed to the unique structure, a high quantity of surface active oxygen species, smaller particle size, oxygen vacancies and good low temperature reduction behavior. The effect of water vapor on catalytic activity was also examined. The introduction of water vapor to the feedstock induced a positive effect on CO oxidation over Mn{sub 2}O{sub 3}-700 catalyst. Furthermore, no obvious drop is observed in activity over catalysts even in the presence of water vapor during 48 h.

  3. O dialogismo e as construções narrativas no game literário brasileiro: Memórias de um Sargento de Milícias

    Patricia Margarida Farias Coelho

    2014-02-01

    Full Text Available Neste estudo, refletimos, a partir da proposta teórica-metodológica sobre o conceito dialogismo proposto por Bakhtin e buscamos depreender como foram construídas as narrativas para os games educativos. Este artigo tem dois objetivos: (i compreender como as narrativas são desenvolvidas para plataformas digitais e, (ii verificar  os aspectos dialógicos desenvolvidos por Bakhtin a partir da análise do jogo online. Dessa forma, tomamos como corpus o game: Memórias de um Sargento de Milícias. Nossa pesquisa encontra-se, em fase de desenvolvimento, mas constatamos que essa nova maneira de ler transforma e contribui positivamente para o acesso à literatura. Dialogism and narrative constructions in the Brazilian literary game Memórias de um Sargento de Milícias (Memoirs of a Militia Sergeant Abstract This study reflects on Bakhtin’s theoretical and methodological proposal about the concept of dialogism and the inferences on the construction of narratives for educational games. This paper has two objectives: (i to understand how narratives for digital platforms are developed, and (ii to check the dialogic aspects developed by Bakhtin from the analysis of the online game. In order to achieve the goals, the corpus chosen is the game Memoirs of a Militia Sergeant. Although this research is also in the development stage, this new way of reading has been found to contribute positively to and transform access to literature. Keywords: Educational game; literary work; dialogism; narrative; education.

  4. Composite Monopack for 120mm Mortar, With Plastic Pallet Adapters on a 42" x 53" Wooden Pallet, MIL-STD-1660 Tests, "Design Criteria for Ammunition Unit Loads", and Extreme Temperature Tests

    Dugan, Jeffery L

    2005-01-01

    ... (AMSRD-AAR-AIL-P) to conduct MIL-STD-1660 Tests to determine if the composite monopack for the 120MM mortar, with plastic pallet adapters on a 42" x 53" wooden pallet, designed by US Army ARDEC and manufactured...

  5. Ada Compiler Validation Summary Report: Certificate Number: 890804S1. 10142 Loral/Rolm Mil-Spec Computers ADE, Revision 3.01 MV 10000 Host and HAWK/32 Target

    1989-08-04

    Date Owners Declaration I, the undersigned, representing agree that as part of the joint Marketing Agreement between Roim Mil-Spec and Data General for...possible. Format pragma NLINE (name (, namei): Where: name Specfies the subprogram or neric unit you want inLined at each calL The subprogam or

  6. Ada Compiler Validation Summary Report: Certificate Number: 890804S1.10141 Loral/Rolm Mil-Spec Computers ADE, Revision 3.01 MV 10000 Host and HAWK/32 Target

    1989-08-04

    undersigned, representing /-- /Wz agree that as part of the joint Marketing Agreement between Rolm Mil-Spec and Data General for the Ada Development...the assembly (e wkhout the pragma. Source Code in the folowing emaple, prama NLINE applie to all tb calls to SQUARE in WrrH INLINF. procedure WITH

  7. A Simple Vortex-Assisted Magnetic Dispersive Solid Phase Microextraction System for Preconcentration and Separation of Triazine Herbicides from Environmental Water and Vegetable Samples Using Fe₃O₄@MIL-100(Fe) Sorbent.

    Nasrollahpour, Atefe; Moradi, Seyyed Ershad

    2018-04-04

    A vortex-assisted magnetic dispersive solid phase microextraction coupled with high-performance liquid chromatography has been developed for the extraction and determination of triazine herbicides by using magnetic metal organic frameworks [Fe₃O₄@MIL-100(Fe)] in environmental water and vegetable samples. The Fe₃O₄@MIL-100(Fe) composite has been characterized by using X-ray diffraction spectroscopy, tunneling electron microscopy, thermogravimetric measurement, and Brunauer-Emmett-Teller analysis. The method is based on the sorption of triazine herbicides on Fe₃O₄@MIL-100(Fe) because of the complex formation between iron oxide nanoparticles and triazine herbicides beside π-π interactions between organic parts of Fe₃O₄@MIL-100(Fe) and triazine herbicides. The experimental parameters for the preconcentration of triazine herbicides, such as the type and volume of the eluent, pH, time of the sorption and desorption, and the amount of the sorbent, were optimized. Under the optimized conditions, the method was linear over the concentration range of 0.0061 to 70 ng/mL for each triazine herbicide, and the correlation coefficients ranged from 0.9988 to 0.9997. The limit of detection of the method at a signal-to-noise ratio of 3 was 2.0 to 5.3 ng/mL. The relative standard deviations for inter- and intraday assays were in the range of 5.8 to 10.2% and 3.8 to 6.3%, respectively.

  8. Supporting inquiry learning by promoting normative understanding of multivariable causality

    Keselman, Alla

    2003-11-01

    Early adolescents may lack the cognitive and metacognitive skills necessary for effective inquiry learning. In particular, they are likely to have a nonnormative mental model of multivariable causality in which effects of individual variables are neither additive nor consistent. Described here is a software-based intervention designed to facilitate students' metalevel and performance-level inquiry skills by enhancing their understanding of multivariable causality. Relative to an exploration-only group, sixth graders who practiced predicting an outcome (earthquake risk) based on multiple factors demonstrated increased attention to evidence, improved metalevel appreciation of effective strategies, and a trend toward consistent use of a controlled comparison strategy. Sixth graders who also received explicit instruction in making predictions based on multiple factors showed additional improvement in their ability to compare multiple instances as a basis for inferences and constructed the most accurate knowledge of the system. Gains were maintained in transfer tasks. The cognitive skills and metalevel understanding examined here are essential to inquiry learning.

  9. De Italo Calvino a Ricardo Piglia, do centro para a margem: o deslocamento como proposta para a literatura deste milênio

    Renato Cordeiro Gomes

    2004-06-01

    Full Text Available O escritor italiano Italo Calvino deixou como testamento literário seis propostas que caracterizariam a literatura do "próximo milênio", mas não teve tempo de redigir a sexta dessas propostas, justamente a "consistência". O escritor argentino Ricardo Piglia, na conferência "Três propostas para o próximo milênio (e cinco dificuldades", proferida na Casa de las Américas, Cuba, em 2000, propõe, então, escrevê-la, não a consistência, mas o "deslocamento, a distância", para equacionar o problema do futuro da literatura e sua função na sociedade, vista, entretanto, a partir da margem, das bordas das tradições centrais da América Hispânica.El escritor italiano Italo Calvino ha dejado como testigo literario seis propuestas para caracterizar la literatura del "próximo milenio", pero no tuvo tiempo de escribir la sexta, justo la que llevaria el nombre de "consistencia". El escritor argentino Ricardo Piglia en su conferencia "Tres propuestas para el próximo milenio (y cinco dificultades", hecha en la Casa de Las Américas, Cuba, año 2000, intenta escribirla - no como consistencia - sino como "desplazamiento, distancia", para equacionar el problema del futuro de la literatura y su función en la sociedad, pero desde el margen, desde el borde de las tradiciones centrales de Hispano-América.The Italan writer Italo Calvino has left as his literary legacy the six proposals that would characterize the literature of the "next millenium", but he had no time to write "consistency", the sixth of these proposals. The Argentinian writer Ricardo Piglia at the "Three proposals for the next millenium (and five difficulties", conference held at "Casa de las Américas", Cuba, in 2000, proposes, therefore, to write the proposals "dislocation" and "distance" in the place of consistency, aiming at solving the problem of literature's future and its role in society, which is seen, however, from the edge, from the border of Spanish America's central

  10. THE SOFTWARE OF THE ADVANCED MIL-STD-1553B MULTIPLEX DATA BUS TESTER AND INTERFACE MODULE: FEATURES AND IMPLEMENTATION DETAILS

    Dmitry E. Gouriev

    2018-03-01

    Full Text Available The UEM-MK is a new module of universal device and parametric tester of multiplex data bus, which meets all requirements for testing equipment for use in validation of devices against requirements of GOST R 52070-2003 (the same as MIL-STD-1553B Notice 4. The module can handle work of bus controller, up to 32 remote terminals and bus monitor/analyser simultaneously, can inject errors of all necessary types. In the article the software of the module is described. The software consist of: the driver, the control panel, the self-test program, the program for validation testing of remote terminals (PTOU, the extended function library, integrated environment (program BPOUEM. The latter three components are top-level components for users and software developments. The driver provides a connection with the module. Control panel provides module identification, self-testing and simplest actions on the bus in interactive mode. The PTOU program provides validation testing of remote terminals in accordance with the GOST R 51765-2001 test plan. The BPOUEM program lets users to create their own scenarios for testing and network environment imitation in interactive mode, whereas the extended function library lets the same in a form of application programs. Both these components also let to record and analyse bus traffic. The purpose, features and implementation details of all mentioned software components are described in the article, however, especial attention is paid to extended function library and the BPOUEM program.

  11. GUERRA, NACIÓN Y DERECHOS A LOS 112 AÑOS DE LA GUERRA DE LOS MIL DÍAS (1899-1902

    Rafael Rubiano Muñoz

    2011-11-01

    Full Text Available A finales del siglo XIX, se produjo la Guerra de los Mil Días, acontecimiento abrupto de las confrontaciones acumuladas de las elites políticas colombianas en un largo ciclo. Bajo el dominio de los gobiernos de la Regeneración (1885-1902, se enfrentaron los conservadores nacionalistas, liderados por Miguel Antonio Caro, y los liberales radicales, dirigidos por Rafael Uribe Uribe, a quienes se les unieron circunstancialmente los conservadores históricos liderados por Carlos Martínez Silva y Marceliano Vélez. El artículo explora el sentido histórico y político de la guerra, se examinan sus consecuencias para el país, y sus incidencias en el siglo XX; se destacan en ese evento bélico, la pérdida de Panamá y la construcción del canal, la dictadura de Rafael Reyes conocido como el “quinquenio” y la propuesta del proyecto de Republicanismo, concebido por Carlos E. Restrepo, presidente entre 1910 a 1914, quien propuso una reforma constitucional, que planteaba las bases del Estado de derecho en Colombia.

  12. Fuel characteristics pertinent to the design of aircraft fuel systems, Supplement I : additional information on MIL-F-7914(AER) grade JP-5 fuel and several fuel oils

    Barnett, Henry C; Hibbard, Robert R

    1953-01-01

    Since the release of the first NACA publication on fuel characteristics pertinent to the design of aircraft fuel systems (NACA-RM-E53A21), additional information has become available on MIL-F7914(AER) grade JP-5 fuel and several of the current grades of fuel oils. In order to make this information available to fuel-system designers as quickly as possible, the present report has been prepared as a supplement to NACA-RM-E53A21. Although JP-5 fuel is of greater interest in current fuel-system problems than the fuel oils, the available data are not as extensive. It is believed, however, that the limited data on JP-5 are sufficient to indicate the variations in stocks that the designer must consider under a given fuel specification. The methods used in the preparation and extrapolation of data presented in the tables and figures of this supplement are the same as those used in NACA-RM-E53A21.

  13. Probing Interactions of N-Donor Molecules with Open Metal Sites within Paramagnetic Cr-MIL-101: A Solid-State NMR Spectroscopic and Density Functional Theory Study.

    Wittmann, Thomas; Mondal, Arobendo; Tschense, Carsten B L; Wittmann, Johannes J; Klimm, Ottokar; Siegel, Renée; Corzilius, Björn; Weber, Birgit; Kaupp, Martin; Senker, Juergen

    2018-02-14

    Understanding host-guest interactions is one of the key requirements for adjusting properties in metal-organic frameworks (MOFs). In particular, systems with coordinatively unsaturated Lewis acidic metal sites feature highly selective adsorption processes. This is attributed to strong interactions with Lewis basic guest molecules. Here we show that a combination of 13 C MAS NMR spectroscopy with state-of-the-art density functional theory (DFT) calculations allows one to unravel the interactions of water, 2-aminopyridine, 3-aminopyridine, and diethylamine with the open metal sites in Cr-MIL-101. The 13 C MAS NMR spectra, obtained with ultrafast magic-angle spinning, are well resolved, with resonances distributed over 1000 ppm. They present a clear signature for each guest at the open metal sites. Based on competition experiments this leads to the following binding preference: water open metal sites, the NMR data offer additional information about the guest and framework dynamics. We expect that our strategy has the potential for probing the binding situation of adsorbate mixtures at the open metal sites of MOFs in general and thus accesses the microscopic interaction mechanisms for this important material class, which is essential for deriving structure-property relationships.

  14. Mediciones épicas: un médico para 7 mil millones de pacientes. New York: Harper Collins Publishers, 2015

    Héctor Gómez Dantés

    2015-07-01

    Full Text Available La lectura de un libro que describe el desarrollo de un innovador método de medición para conocer con la mayor precisión cómo enferman y mueren las poblaciones en el mundo no parecería tener ningún atractivo para esos 7 mil millones de personas mencionadas en el texto de Jeremy N. Smith. Uno se pregunta: ¿para qué queremos saber las razones de nuestra posible muerte, si la sociedad nos mueve a hacer todo lo posible por alcanzarla y de manera hasta prematura? Lo cierto es que los sistemas encargados de atender nuestra salud o, mejor dicho, nuestras enfermedades,desconocen la verdadera dimensión de los problemas que nos aquejan a nivel global y contabilizan razones o causas a nivel individual sin el menor sentido de precisión.razones o causas a nivel individual sin el menor sentido de precisión...

  15. A pesquisa em saúde e os objetivos do milênio: desafios e oportunidades globais, soluções e políticas nacionais

    Morel Carlos M.

    2004-01-01

    Full Text Available Saúde, ciência e tecnologia são requisitos para o desenvolvimento econômico e social. Os Objetivos de Desenvolvimento do Milênio da ONU para 2015 representam um imenso desafio para os países em desenvolvimento. Esses países terão de organizar sistemas de pesquisa em saúde baseados em prioridades sanitárias e assegurar a incorporação dos resultados às políticas e ações de saúde. Avanços na área biomédica, em particular em genômica, abrem novas oportunidades, mas impõem desafios adicionais. O Brasil, possuidor de um forte parque industrial e uma vigorosa comunidade científica, tem capacidade para desenvolver um sistema de pesquisas em saúde capaz de contribuir efetivamente para o cumprimento das metas da ONU.

  16. Fitodefensivos em plantas medicinais: macromoléculas hidrofílicas de folhas de mil folhas (Achillea millefolium L. inibem o crescimento in vitro de bactérias fitopatogênicas Agrochemicals in medicinal plants: hydrophilic macromolecules from leaves of "mil folhas" (Achillea millefolium L. inhibit in vitro growth of phytopathogenic bacteria

    N.G. Tessarollo

    2013-01-01

    Full Text Available Extratos aquosos da planta medicinal Achillea millefolium contêm macromoléculas de interesse para desenvolver fitodefensivos para a agricultura. Duas frações de mil folhas foram obtidas por ultrafiltração, E1 (contendo moléculas maiores que 30 kDa, e E3 (peptídeos entre 1 e 10 kDa que inibiram o crescimento das bactérias fitopatogênicas Ralstonia solanacearum, gram-negativa, e Clavibacter michiganensis subsp. michiganensis, gram-positiva, com dependência de concentração. Os valores de concentração inibitória mínima (CIM para ambos os extratos e bactérias foram baixos, entre 20 e 80µM. A CIM relativa à proteína total evidenciou a presença de macromoléculas muito ativas em E3, embora com baixa concentração proteica. E3 se aplica à prospecção de peptídeos antimicrobianos. Estimar a CIM relativa à quantidade de amostra vegetal valorizou o potencial antimicrobiano natural de E1, que contém alta concentração proteica. E1e E3 se aplicam ao desenvolvimento de fitodefensivos para uso biotecnológico. A ultrafiltração fracionou as amostras de forma nativa, rápida, e com baixo custo; além de dessalinizar, clarificar, purificar, e concentrar E1 e E3. Esse estudo inédito sobre a separômica e a ação antimicrobiana de extratos macromoleculares aquosos de mil folhas sugere que plantas cicatrizantes podem apresentar grande potencial para desenvolver fitodefensivos agrícolas naturais não danosos, à semelhança de medicamentos fitoterápicos.Aqueous extracts from the medicinal plant Achillea millefolium contain macromolecules of interest to develop agrochemicals for agriculture. Two fractions of "mil folhas" were obtained by ultrafiltration, E1 (containing molecules larger than 30 kDa and E3 (peptides between 1 and 10 kDa, which inhibited the growth of phytopathogenic bacteria Ralstonia solanacearum, gram-negative, and Clavibacter michiganensis subsp. michiganensis, gram-positive, concentration-dependent. The values of

  17. Action Recognition Using Discriminative Structured Trajectory Groups

    Atmosukarto, Indriyati

    2015-01-06

    In this paper, we develop a novel framework for action recognition in videos. The framework is based on automatically learning the discriminative trajectory groups that are relevant to an action. Different from previous approaches, our method does not require complex computation for graph matching or complex latent models to localize the parts. We model a video as a structured bag of trajectory groups with latent class variables. We model action recognition problem in a weakly supervised setting and learn discriminative trajectory groups by employing multiple instance learning (MIL) based Support Vector Machine (SVM) using pre-computed kernels. The kernels depend on the spatio-temporal relationship between the extracted trajectory groups and their associated features. We demonstrate both quantitatively and qualitatively that the classification performance of our proposed method is superior to baselines and several state-of-the-art approaches on three challenging standard benchmark datasets.

  18. Metal-organic framework MIL-101 as sorbent based on double-pumps controlled on-line solid-phase extraction coupled with high-performance liquid chromatography for the determination of flavonoids in environmental water samples.

    Liu, Yue; Hu, Jia; Li, Yan; Li, Xiao-Shuang; Wang, Zhong-Liang

    2016-10-01

    A novel method with high sensitivity for the rapid determination of chrysin, apigenin and luteolin in environment water samples was developed by double-pumps controlled on-line solid-phase extraction (SPE) coupled with high-performance liquid chromatography (HPLC). In the developed technique, metal organic framework MIL-101 was synthesized and applied as a sorbent for SPE. The as-synthesized MIL-101 was characterized by scanning electron microscope, X-ray diffraction spectrometry, thermal gravimetric analysis and micropore physisorption analysis. The MIL-101 behaved as a fast kinetics in the adsorption of chrysin, apigenin and luteolin. On-line SPE of chrysin, apigenin and luteolin was processed by loading a sample solution at a flow rate of 1.0 mL/min for 10 min. The extracted analytes were subsequently eluted into a ZORBAX Bonus-RP analytical column (25 cm long × 4.6 mm i.d.) for HPLC separation under isocratic condition with a mobile phase (MeOH: ACN: 0.02 M H 3 PO 4 = 35:35:30) at a flow rate of 1.0 mL/min. Experimental conditions, including ionic strength, sample pH, sample loading rates, sample loading time and desorption analytes time, were further optimized to obtain efficient preconcentration and high-precision determination of the analytes mentioned above. The method achieved the merits of simplicity, rapidity, sensitivity, wide linear range and high sample throughput. The possible mechanism for the adsorption of flavonoids on MIL-101 was proposed. The developed method has been applied to determine trace chrysin, apigenin and luteolin in a variety of environmental water samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A new indium metal-organic 3D framework with 1,3,5-benzenetricarboxylate, MIL-96 (In), containing μ 3-oxo-centered trinuclear units and a hexagonal 18-ring network

    Volkringer, Christophe; Loiseau, Thierry

    2006-01-01

    A new indium trimesate In 12 O(OH) 12 ({OH} 4 ,{H 2 O} 5 )[btc] 6 .∼31H 2 O, called MIL-96 (btc = 1,3,5-benzenetricarboxylate or trimesate species) was hydrothermally synthesized under mild condition (210 deg. C, 5 h) in the presence of trimethyl 1,3,5-benzenetricarboxylate in water and characterized by single-crystal X-ray diffraction technique. The MIL-96 (In) structure exhibits a three-dimensional metal-organic framework containing isolated trinuclear μ 3 -oxo-bridged indium clusters and infinite chains of InO 4 (OH) 2 and InO 2 (OH) 3 (H 2 O) octahedra generating a hexagonal network based on 18-membered ring. The two types of indium entities are connected to each other through the trimesate species which induce corrugated chains of indium octahedra, linked via μ 2 -hydroxo bonds with the specific -cis-cis-trans- sequence. The 3D framework of MIL-96 reveals three kind of cavities (two of them have estimated ∼ 400 A 3 volumes), in which are encapsulated free water molecules. The latter species are removed upon heating at 150 deg. C

  20. Solid-phase extraction with the metal-organic framework MIL-101(Cr) combined with direct analysis in real time mass spectrometry for the fast analysis of triazine herbicides.

    Li, Xianjiang; Xing, Jiawei; Chang, Cuilan; Wang, Xin; Bai, Yu; Yan, Xiuping; Liu, Huwei

    2014-06-01

    MIL-101(Cr) is an excellent metal-organic framework with high surface area and nanoscale cavities, making it promising in solid-phase extraction. Herein, we used MIL-101(Cr) as a solid-phase extraction packing material combined with fast detection of direct analysis in real time mass spectrometry (DART-MS) for the analysis of triazine herbicides. After systematic optimization of the operation parameters, including the gas temperature of DART, the moving speed of the 1D platform, solvent for desorption, amount of MIL-101(Cr) extraction time, eluent volume and salt concentration, this method can realize the simultaneous detection of five kinds of triazine herbicides. The limits of detection were 0.1∼0.2 ng/mL and the linear ranges covered more than two orders of magnitude with the quantitation limits of 0.5∼1 ng/mL. Moreover, the developed method has been applied for the analysis of lake water samples and the recoveries for spiked analytes were in the range of 85∼110%. These results showed that solid-phase extraction with metal-organic frameworks is an efficient sample preparation approach for DART-MS analysis and could find more applications in environmental analysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Learning How to Learn

    Lauridsen, Karen M.; Lauridsen, Ole

    Ole Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Karen M. Lauridsen, Aarhus School of Business and Social Sciences, Aarhus University, Denmark Learning Styles in Higher Education – Learning How to Learn Applying learning styles (LS) in higher education...... by Constructivist learning theory and current basic knowledge of how the brain learns. The LS concept will thus be placed in a broader learning theoretical context as a strong learning and teaching tool. Participants will be offered the opportunity to have their own LS preferences established before...... teaching leads to positive results and enhanced student learning. However, learning styles should not only be considered a didactic matter for the teacher, but also a tool for the individual students to improve their learning capabilities – not least in contexts where information is not necessarily...

  2. Learning to Learn.

    Weiss, Helen; Weiss, Martin

    1988-01-01

    The article reviews theories of learning (e.g., stimulus-response, trial and error, operant conditioning, cognitive), considers the role of motivation, and summarizes nine research-supported rules of effective learning. Suggestions are applied to teaching learning strategies to learning-disabled students. (DB)

  3. Constrained Deep Weak Supervision for Histopathology Image Segmentation.

    Jia, Zhipeng; Huang, Xingyi; Chang, Eric I-Chao; Xu, Yan

    2017-11-01

    In this paper, we develop a new weakly supervised learning algorithm to learn to segment cancerous regions in histopathology images. This paper is under a multiple instance learning (MIL) framework with a new formulation, deep weak supervision (DWS); we also propose an effective way to introduce constraints to our neural networks to assist the learning process. The contributions of our algorithm are threefold: 1) we build an end-to-end learning system that segments cancerous regions with fully convolutional networks (FCNs) in which image-to-image weakly-supervised learning is performed; 2) we develop a DWS formulation to exploit multi-scale learning under weak supervision within FCNs; and 3) constraints about positive instances are introduced in our approach to effectively explore additional weakly supervised information that is easy to obtain and enjoy a significant boost to the learning process. The proposed algorithm, abbreviated as DWS-MIL, is easy to implement and can be trained efficiently. Our system demonstrates the state-of-the-art results on large-scale histopathology image data sets and can be applied to various applications in medical imaging beyond histopathology images, such as MRI, CT, and ultrasound images.

  4. Atuação do pediatra nos primeiros mil dias da criança: a busca pela nutrição e desenvolvimento saudáveis

    Antonio Jose Ledo Alves da Cunha

    2015-12-01

    Full Text Available Resumo Objetivos: Descrever o conceito dos primeiros mil dias, sua importância para a saúde e ações a serem implantadas, em especial pelos pediatras, para que a criança alcance nutrição e desenvolvimento saudáveis. Fonte dos dados: Revisão não sistemática nas bases SciELO, Lilacs, Medline, Scopus e Web of Science nos últimos dez anos com os termos mil dias, nutrição infantil, desenvolvimento infantil, infância, criança. Busca não sistemática na Internet de organizações que adotam o conceito dos mil dias e emitem recomendações sobre a saúde da criança. Síntese dos dados: Os primeiros mil dias vão da concepção até o fim do segundo ano de vida. É um importante período para intervenções que garantam nutrição e desenvolvimento saudáveis, que trarão benefícios em todo o ciclo de vida. As crianças devem receber alimentação adequada, por meio de nutrição pré-natal adequada, aleitamento materno exclusivo nos primeiros seis meses, adição de alimentos complementares adequados e continuação da amamentação até os dois anos. Face à condição de dependência absoluta de cuidados de um adulto, é fundamental que tenham um ambiente propício e acolhedor necessário para desenvolver laços fortes com seus cuidadores e lançar as bases para um desenvolvimento pleno e saudável. Conclusões: O pediatra, junto com outros profissionais, pode atuar na promoção de ações com ênfase no conceito dos primeiros mil dias que garantam a nutrição e o desenvolvimento saudáveis da criança. Focalizar ações nesse período poderá aumentar as chances de a criança ter uma vida saudável e produtiva no futuro, fortalecer famílias e comunidades e contribuir para quebrar o ciclo intergeracional da pobreza.

  5. El recluta. Testimonio literario del impacto de la Guerra de los Mil Días en la familia antioqueña

    Jair Alexis Trujillo Mosquera

    2015-08-01

    Full Text Available Este ensayo da cuenta del resultado parcial de un estudio mayor, cuyo propósito fundamental es mostrar el impacto de la guerra en la esfera doméstica (social. Para este propósito, se analizó El recluta, antología de cuentos sobre la Guerra de los Mil Días. Esta obra tiene un valor fundamental y es que fue escrita durante la contienda, rasgo que la diferencia de casi toda la literatura de este período (y tema. La pregunta por la familia aparece de manera explícita en el libro: mediante convocatoria, en el año 1901, el periódico El Cascabel dirigido por H. Gaviria, propuso: “el siguiente tema para un cuento corto que no traspase los límites de tres columnas de El Cascabel: Un pobre recluta que ha hecho campaña en la presente contienda civil y que á su regreso encuentra en su hogar... lo que quieran que encuentre los Sres. Tomás Carrasquilla, Efe Gómez […]”. El recluta es valioso porque nos permite analizar la guerra desde una óptica distinta; este libro nos ofrece una mirada bifocal, ya que podemos adentrarnos en las vidas, tanto del recluta, como de su entorno, su familia, su vida doméstica; en otras palabras, dejar de mirar los ejércitos para ir a las “gentes” que están del otro lado de los campos de batalla. La guerra tiene la particularidad de actuar de manera estructural, sus tentáculos van mucho más allá de lo obvio, el combate. This essay accounts for partial results of a higher research which basic purpose is to show the impact of war on the domestic (social scenario. For this purpose, “El Recluta” (anthology of short stories about the “Guerra de los Mil Días” war. This book has a special value since it was written during the war, which is a trait that distinguishes it from almost the entire literature (and topics of such a period. The question about the family appears explicitly in the book: through a call made in 1901, newspaper “El Cascabel” directed by H. Gaviria, made the following proposal

  6. System for Comparing Gamma Sources Varying by Ratios of up to 1:1000; Dispositivo Gamma que para Comparar Fuentes Difieren Hasta uno En Mil

    Tejera Rivera, A.; Navarro Cuevas, D. [Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico)

    1967-03-15

    , principalmente gamma y de un mismo radioisotopo, cuando difieren en una relacion del orden de uno a miL La utilidad inmediata de este dispositivo es la elaboracion de patrones gamma para la calibracion de camaras de ionizacion que requieren actividades del orden de milicuries de radioisotopos, como el {sup 60}Co o el {sup 131}I, a partir de patrones respectivos con actividades del orden del microcurie. El principio en que se basan los dispositivos construidos es restringir el paso de la luz emitida por el cristal de centelleo al tubo fotomultiplicador. En el primer dispositivo se enmascaro la mitad de la cara del cristal de centelleo, Nal (TI), y la mitad de la cara del foto-multiplicador de tal forma que haciendo girar el cristal se sobreponen las mascaras y se restringe la luz desde 50% hasta 0%. Con este dispositivo se ha conseguido en la practica comparar actividades de uno a veinte. En el segundo dispositivo se han dispuesto cinco diafragmas en un disco rotatorio que permiten el paso desde 100% de luz hasta 1%. Usando este dispositivo es posible comparar fuentes que difieren hasta mil veces en actividad, manteniendo dentro de 100 000 cuentas/min la lectura del escalador. Este procedimiento resulta ventajoso principalmente porque disminuye el error debido a diferencias del tiempo muerto instrumental para los recuentos realizados con fuentes de muy diferente actividad y permite, ademas, comparar estas muestras usando un blindaje de dimensiones reducidas. (author)

  7. Learning Styles.

    Missouri Univ., Columbia. Coll. of Education.

    Information is provided regarding major learning styles and other factors important to student learning. Several typically asked questions are presented regarding different learning styles (visual, auditory, tactile and kinesthetic, and multisensory learning), associated considerations, determining individuals' learning styles, and appropriate…

  8. UN MONSTRUO DE MIL CABEZAS

    Miriam Bautista González

    2015-01-01

    Full Text Available La comunicación interpersonal, muchas veces es dejada de lado por los comunicólogos, sin embargo tiene suma gravitación en las relaciones cotidianas entre las personas y en los procesos comunicacionales, toca el lenguaje de los gestos, la (in comunicación política, ceremonial y protocolo, intermediación en la comunicación, los jóvenes se incomunican. Respecto al Periodismo Investigativo señala que a pesar de los riesgos que implica el periodismo investigativo, muchos profesionales de América Latina no dudan en practicarlo, escudriñando muchas veces en temas que de no ser por ellos permanecerían ocultos. En otro artículo se habla de la importante repercusión que tuvo en América Latina el concurso CHASQUI, el que contó con la participación de profesionales de todo el continente. Incluye la entrega de entrevistas a destacados comunicadores de América Latina. Una sección está dedicada a las nuevas tecnologías: red de noticias y transmisiones vía satélite.

  9. Atributos químicos e físicos de um argissolo cultivado com Panicum maximum Jacq. cv. IPR-86 Milênio, sob lotação rotacionada e adubado com nitrogênio Chemical and physical attributes in an anfisol cultivated with Panicum maximum Jacq. cv. IPR-86 Milênio, under rotational stocking and fertilized with nitrogen

    Patrícia Sarmento

    2008-02-01

    Full Text Available A avaliação dos atributos químicos e físicos do solo é necessária em estudos que exploram intensivamente os sistemas de pastejo. No presente trabalho, objetivou-se avaliar as variações nos atributos físicos e químicos de um Argissolo cultivado com capim-milênio, sob pastejo, no intervalo compreendido entre outubro/2001 e maio/2002, no quinto ano de aplicação sucessiva das seguintes doses de N: 0, 150, 300 e 450 kg ha-1. Após os cinco anos de aplicação de 450 kg ha-1 de N, o teor de MO aumentou em 5 g dm-3, o que resultou em aumento da CTC. No período de outubro/2001 a maio/2002 houve diminuição nos valores de pH e de V com a aplicação de N. A densidade do solo variou pouco com a adubação nitrogenada; a percentagem de microporos aumentou e a de macroporos diminuiu na camada de 0-5 cm com o aumento das doses de N, mas a porosidade total permaneceu constante; e a resistência à penetração, quando o solo apresentava 90 g kg-1 de água, não foi afetada pelas doses de N e não foi restritiva ao crescimento das plantas.It is necessary to evaluate the soil physical and chemical attributes in studies that explore grazing systems intensively. In this work the variation in physical and chemical attributes of an Alfissol cultivated with Panicum maximum Jacq. cv. IPR-86 Milênio under grazing were evaluated from October 2001 to May 2002, in the fifth year of consecutive N application at rates of 0, 150, 300, and 450 kg ha-1. After five successive applications of 450 kg ha-1 N, the OM content increased 5 g dm-3, which resulted in CEC increase. From October 2001 to May 2002 the pH and basis saturation degree decreased with the increasing N rates. The range in soil density with N fertilization was small; the micropore percentage increased and the macropore percentage decreased in the 0-5 cm layer with increasing N rates, but the total porosity remained constant; and the soil penetration resistance at 90 g ha-1 of water was not

  10. Learning Networks, Networked Learning

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  11. Antes de la separación de Panamá: la guerra de los mil días, el contexto internacional y el canal

    Thomas Fischer

    1998-01-01

    Full Text Available Los contemporáneos de finales del siglo pasado eran conscientes de vivir en un periodo de transición, que llevaba en su seno profundas contradicciones, sin saber qué les depararia el nuevo siglo. Así pues, se sentían los hombres que hacían historia al final del siglo pasado en Colombia. En 1899 empezó una guerra civil, la llamada guerra de los mil días. Este enfrentamiento significó la culminación de una serie de guerras civiles que marcaron el siglo XIX. Aunque el conflicto armado entre liberales y conservadores no afectó a todas las regiones de la misma manera, dividió a la población más que nunca. Fue quizá la guerra más desastrosa, tanto en lo referente a los daños ocasionados en la economía nacional como en relación a las bajas humanas registradas. Un año después del final de la guerra se separó el departamento de Panamá. Esto se debió a la fragilidad del concepto nacional de Colombia que tenía un sistema político poco apto para asistir a la negociación del problema más urgente de la agenda internacional del país: la transacción de los derechos para excavar y construir por territorio colombiano un canal que uniría el Oceano Atlántico con el Pacífico en favor de los Estados Unidos. Con la ocupación de Cuba y Puerto Rico esta potencia se había establecido como poder hegemónico en la región, desplazando a las potencias europeas. No cabe duda de que la crisis que atravesó Colombia marcó un cambio fundamental en la conciencia nacional.

  12. In-tube solid-phase microextraction based on NH2-MIL-53(Al)-polymer monolithic column for online coupling with high-performance liquid chromatography for directly sensitive analysis of estrogens in human urine.

    Luo, Xialin; Li, Gongke; Hu, Yufei

    2017-04-01

    In this work, a novel NH 2 -MIL-53(Al) incorporated poly(styrene-divinylbenzene-methacrylic acid) (poly(St-DVB-MAA)) monolith was prepared via chemical fabrication. Moreover, it has been efficiently applied to the in-tube solid-phase microextraction (SPME) for online coupling with high-performance liquid chromatography (HPLC) to the direct determination of five estrogens in human urine samples. The NH 2 -MIL-53(Al)-polymer monolith was suitable for in-tube SPME owing to its good permeability, high extraction efficiency, chemical stability, good reproducibility and long lifetime. The extraction conditions including extraction solvent, pH of sample solution, flow rate of extraction and desorption, and desorption volume were investigated. Under the optimum conditions, the enrichment factors were 180-304 and saturated amounts of extraction were 2326-21393 pmol for estriol, 17β-estradiol, estrone, ethinyl estradiol and progesterone, respectively. The adsorption mechanism was also explored which contributed to its strong extraction to target compounds. The proposed method had low limit of detection (2.0-40ng/L) and good linearity (with R 2 between 0.9908 and 0.9978). Four endogenous estrogens were detected in urine samples and the recoveries of all five analytes were ranged from 75.1-120% with relative standard deviations (RSDs) less than 8.7%. The results showed that the proposed online SPME-HPLC method based on NH 2 -MIL-53(Al)-polymer monolithic column was highly sensitive for directly monitoring trace amount of estrogens in human urine sample. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Portable Tablets in Science Museum Learning: Options and Obstacles

    Gronemann, Sigurd Trolle

    2017-06-01

    Despite the increasing use of portable tablets in learning, their impact has received little attention in research. In five different projects, this media-ethnographic and design-based analysis of the use of portable tablets as a learning resource in science museums investigates how young people's learning with portable tablets matches the intentions of the museums. By applying media and information literacy (MIL) components as analytical dimensions, a pattern of discrepancies between young people's expectations, their actual learning and the museums' approaches to framing such learning is identified. It is argued that, paradoxically, museums' decisions to innovate by introducing new technologies, such as portable tablets, and new pedagogies to support them conflict with many young people's traditional ideas of museums and learning. The assessment of the implications of museums' integration of portable tablets indicates that in making pedagogical transformations to accommodate new technologies, museums risk opposing didactic intention if pedagogies do not sufficiently attend to young learners' systemic expectations to learning and to their expectations to the digital experience influenced by their leisure use.

  14. A theoretical design for learning model addressing the networked society

    Levinsen, Karin; Nielsen, Janni; Sørensen, Birgitte Holm

    2010-01-01

    The transition from the industrial to the networked society produces contradictions that challenges the educational system and force it to adapt to new conditions. In a Danish virtual Master in Information and Communication Technologies and Learning (MIL) these contradictions appear as a field of...... which enables students to develop Networked Society competencies and maintain progression in the learning process also during the online periods. Additionally we suggest that our model contributes to the innovation of a networked society's design for learning....... is continuously decreasing. We teach for deep learning but are confronted by students' cost-benefit strategies when they navigate through the study programme under time pressure. To meet these challenges a Design for Learning Model has been developed. The aim is to provide a scaffold that ensures students......' acquisition of the subject matter within a time limit and at a learning quality that support their deep learning process during a subsequent period of on-line study work. In the process of moving from theory to application the model passes through three stages: 1) Conceptual modelling; 2) Orchestration, and 3...

  15. Learning Problems

    ... Staying Safe Videos for Educators Search English Español Learning Problems KidsHealth / For Kids / Learning Problems What's in ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...

  16. Synthesis, characterization and sorption properties of functionalized Cr-MIL-101-X (X=–F, –Cl, –Br, –CH{sub 3}, –C{sub 6}H{sub 4}, –F{sub 2}, –(CH{sub 3}){sub 2}) materials

    Buragohain, Amlan [Department of Chemistry, Indian Institute of Technology Guwahati, 781039 Assam (India); Couck, Sarah [Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); Van Der Voort, Pascal [Department of Inorganic and Physical Chemistry, Ghent University, COMOC – Center for Ordered Materials, Organometallics and Catalysis, Krijgslaan 281-S3, 9000 Ghent (Belgium); Denayer, Joeri F.M. [Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels (Belgium); Biswas, Shyam, E-mail: sbiswas@iitg.ernet.in [Department of Chemistry, Indian Institute of Technology Guwahati, 781039 Assam (India)

    2016-06-15

    Four existing and three new functionalized chromium terephthalates having MIL-101 topology and denoted as Cr-MIL-101-X (existing ones with X=–F, 1-F; –Cl, 2-Cl; –Br, 3-Br; –CH{sub 3}, 4-CH{sub 3}; new ones with X=–C{sub 6}H{sub 4}, 5-C{sub 6}H{sub 4}; –F{sub 2}, 6-F{sub 2}, –(CH{sub 3}){sub 2}, 7-(CH{sub 3}){sub 2}) were synthesized under hydrothermal conditions. All the materials except 5-C{sub 6}H{sub 4} could be prepared by a general synthetic route, in which the mixtures of CrO{sub 3}, H{sub 2}BDC-X (BDC=1,4-benzenedicarboxylate) linkers, conc. HCl and water with a molar ratio of 1:1:3.9:222.2 were reacted at 180 °C for 144 h. Compared to the 144 h of synthesis time, three of the compounds, namely 1-Cl, 2-Br and 5-C{sub 6}H{sub 4}, could be prepared in much shorter reaction times (12–18 h at 180–210 °C). The materials possess high thermal stability up to 270–300 °C in an air atmosphere. The activated compounds exhibit significant porosity (S{sub BET} range: 1273–2135 m{sup 2} g{sup −1}). At 0 °C and 1 bar, the CO{sub 2} adsorption capacities of the compounds fall in the 1.7–2.9 mmol g{sup −1} range. Compounds 1-F and 6-F{sub 2} showed enhanced CO{sub 2} uptake values compared to parent Cr-MIL-101. The benzene adsorption capacities of the compounds lie in the range of 66.2–139.5 molecules per unit cell at 50 °C and p/p{sub 0}=0.35. The increased benzene uptake value of 1-F compared to un-functionalized Cr-MIL-101 and 4-CH{sub 3} suggests that the fluorination has induced more hydrophobicity in Cr-MIL-101 as compared to the methylation. - Graphical abstract: Benzene adsorption by seven functionalized Cr-MIL-101-X metal-organic framework (MOF) materials Display Omitted - Highlights: • Seven functionalized Cr-MIL-101-X materials were synthesized solvothermally. • All Cr-MIL-101-X materials exhibited high thermal stability up to 270–300 °C in air. • All Cr-MIL-101-X compounds displayed considerable porosity towards N{sub 2

  17. Synthesis, characterization and sorption properties of functionalized Cr-MIL-101-X (X=–F, –Cl, –Br, –CH3, –C6H4, –F2, –(CH3)2) materials

    Buragohain, Amlan; Couck, Sarah; Van Der Voort, Pascal; Denayer, Joeri F.M.; Biswas, Shyam

    2016-01-01

    Four existing and three new functionalized chromium terephthalates having MIL-101 topology and denoted as Cr-MIL-101-X (existing ones with X=–F, 1-F; –Cl, 2-Cl; –Br, 3-Br; –CH 3 , 4-CH 3 ; new ones with X=–C 6 H 4 , 5-C 6 H 4 ; –F 2 , 6-F 2 , –(CH 3 ) 2 , 7-(CH 3 ) 2 ) were synthesized under hydrothermal conditions. All the materials except 5-C 6 H 4 could be prepared by a general synthetic route, in which the mixtures of CrO 3 , H 2 BDC-X (BDC=1,4-benzenedicarboxylate) linkers, conc. HCl and water with a molar ratio of 1:1:3.9:222.2 were reacted at 180 °C for 144 h. Compared to the 144 h of synthesis time, three of the compounds, namely 1-Cl, 2-Br and 5-C 6 H 4 , could be prepared in much shorter reaction times (12–18 h at 180–210 °C). The materials possess high thermal stability up to 270–300 °C in an air atmosphere. The activated compounds exhibit significant porosity (S BET range: 1273–2135 m 2 g −1 ). At 0 °C and 1 bar, the CO 2 adsorption capacities of the compounds fall in the 1.7–2.9 mmol g −1 range. Compounds 1-F and 6-F 2 showed enhanced CO 2 uptake values compared to parent Cr-MIL-101. The benzene adsorption capacities of the compounds lie in the range of 66.2–139.5 molecules per unit cell at 50 °C and p/p 0 =0.35. The increased benzene uptake value of 1-F compared to un-functionalized Cr-MIL-101 and 4-CH 3 suggests that the fluorination has induced more hydrophobicity in Cr-MIL-101 as compared to the methylation. - Graphical abstract: Benzene adsorption by seven functionalized Cr-MIL-101-X metal-organic framework (MOF) materials Display Omitted - Highlights: • Seven functionalized Cr-MIL-101-X materials were synthesized solvothermally. • All Cr-MIL-101-X materials exhibited high thermal stability up to 270–300 °C in air. • All Cr-MIL-101-X compounds displayed considerable porosity towards N 2 , CO 2 and benzene. • Mono- and di-fluorinated Cr-MIL-101 materials showed enhanced CO 2 adsorption capacities.

  18. Learning about Learning

    Siegler, Robert S.

    2004-01-01

    The field of children's learning was thriving when the Merrill-Palmer Quarterly was launched; the field later went into eclipse and now is in the midst of a resurgence. This commentary examines reasons for these trends, and describes the emerging field of children's learning. In particular, the new field is seen as differing from the old in its…

  19. Learning to Learn Differently

    Olsen, Trude Høgvold; Glad, Tone; Filstad, Cathrine

    2018-01-01

    Purpose: This paper aims to investigate whether the formal and informal learning patterns of community health-care nurses changed in the wake of a reform that altered their work by introducing new patient groups, and to explore whether conditions in the new workplaces facilitated or impeded shifts in learning patterns. Design/methodology/approach:…

  20. A combination of computational-experimental study on metal-organic frameworks MIL-53(Al) as sorbent for simultaneous determination of estrogens and glucocorticoids in water and urine samples by dispersive micro-solid-phase extraction coupled to UPLC-MS/MS.

    Gao, Guihua; Li, Sijia; Li, Shuo; Wang, Yudan; Zhao, Pan; Zhang, Xiangyu; Hou, Xiaohong

    2018-04-01

    In this work, computational and experimental methods were used to study the adsorption of estrogens and glucocorticoids on metal-organic frameworks (MOFs). Computer-aided molecular simulation was applied to predict the adsorption of eight analytes on four MOFs (MIL-101(Cr), MIL-100(Fe), MIL-53(Al), and UiO-66(Zr)) by examining molecular interactions and calculating free binding energies. Subsequently, the four water-stable MOFs were synthesized and evaluated as adsorbents for the target hormones in aqueous solution. As the MOF exhibiting the highest adsorption capacity in both computations and experiments, MIL-53(Al) was chosen as a sorbent to develop a dispersive micro-solid-phase extraction procedure coupled to ultra-performance liquid chromatography tandem mass spectrometry for simultaneous determination of the target analytes in water and human urine samples. Experimental parameters affecting the extraction recoveries, including pH, ionic strength, MIL-53(Al) amount, extraction time, desorption time, and desorption solvent, were optimized. The optimized method provided a linear range of 0.005025-368.6μg/L with good correlation coefficients (0.9982 ≤ r 2 ≤ 0.9992), and limits of detection (S/N = 3) and quantification (S/N = 10) of 0.0015-1.0μg/L and 0.005-1.8μg/L, respectively. The analyte recoveries were in the range of 80.6-98.4% in water samples and 88.4-93.2% in urine samples. Furthermore, MIL-53(Al) showed good stability over 10 extraction cycles (RSD extraction efficiencies for MOFs and targets, providing new directions for the development and utilization of MOFs. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Distance Learning

    Braddock, Joseph

    1997-01-01

    A study reviewing the existing Army Distance Learning Plan (ADLP) and current Distance Learning practices, with a focus on the Army's training and educational challenges and the benefits of applying Distance Learning techniques...

  2. Blended learning

    Dau, Susanne

    2016-01-01

    Blended Learning has been implemented, evaluated and researched for the last decades within different educational areas and levels. Blended learning has been coupled with different epistemological understandings and learning theories, but the fundamental character and dimensions of learning...... in blended learning are still insufficient. Moreover, blended learning is a misleading concept described as learning, despite the fact that it fundamentally is an instructional and didactic approach (Oliver & Trigwell, 2005) addressing the learning environment (Inglis, Palipoana, Trenhom & Ward, 2011......) instead of the learning processes behind. Much of the existing research within the field seems to miss this perspective. The consequence is a lack of acknowledgement of the driven forces behind the context and the instructional design limiting the knowledge foundation of learning in blended learning. Thus...

  3. Learn, how to learn

    Narayanan, M.

    2002-12-01

    Ernest L. Boyer, in his 1990 book, "Scholarship Reconsidered: Priorities of the Professorate" cites some ground breaking studies and offers a new paradigm that identifies the need to recognize the growing conversation about teaching, scholarship and research in the Universities. The use of `ACORN' model suggested by Hawkins and Winter to conquer and mastering change, may offer some helpful hints for the novice professor, whose primary objective might be to teach students to `learn how to learn'. Action : It is possible to effectively change things only when a teaching professor actually tries out a new idea. Communication : Changes are successful only when the new ideas effectively communicated and implemented. Ownership : Support for change is extremely important and is critical. Only strong commitment for accepting changes demonstrates genuine leadership. Reflection : Feedback helps towards thoughtful evaluation of the changes implemented. Only reflection can provide a tool for continuous improvement. Nurture : Implemented changes deliver results only when nurtured and promoted with necessary support systems, documentation and infrastructures. Inspired by the ACORN model, the author experimented on implementing certain principles of `Total Quality Management' in the classroom. The author believes that observing the following twenty principles would indeed help the student learners how to learn, on their own towards achieving the goal of `Lifelong Learning'. The author uses an acronym : QUOTES : Quality Underscored On Teaching Excellence Strategy, to describe his methods for improving classroom teacher-learner participation. 1. Break down all barriers. 2. Create consistency of purpose with a plan. 3. Adopt the new philosophy of quality. 4. Establish high Standards. 5. Establish Targets / Goals. 6. Reduce dependence on Lectures. 7. Employ Modern Methods. 8. Control the Process. 9. Organize to reach goals. 10. Prevention vs. Correction. 11. Periodic Improvements. 12

  4. Intentional Learning Vs Incidental Learning

    Shahbaz Ahmed

    2017-01-01

    This study is conducted to demonstrate the knowledge of intentional learning and incidental learning. Hypothesis of this experiment is intentional learning is better than incidental learning, participants were demonstrated and were asked to learn the 10 non sense syllables in a specific sequence from the colored cards in the end they were asked to recall the background color of each card instead of non-sense syllables. Independent variables of the experiment are the colored cards containing n...

  5. Posthuman learning

    Hasse, Cathrine

    This book shall explore the concept of learning from the new perspective of the posthuman. The vast majority of cognitive, behavioral and part of the constructionist learning theories operate with an autonomous individual who learn in a world of separate objects. Technology is (if mentioned at all......) understood as separate from the individual learner and perceived as tools. Learning theory has in general not been acknowledging materiality in their theorizing about what learning is. A new posthuman learning theory is needed to keep up with the transformations of human learning resulting from new...... technological experiences. One definition of learning is that it is a relatively permanent change in behavior as the result of experience. During the first half of the twentieth century, two theoretical approaches dominated the domain of learning theory: the schools of thought commonly known as behaviorism...

  6. Learning e-Learning

    Gabriel ZAMFIR

    2009-01-01

    Full Text Available What You Understand Is What Your Cognitive Integrates. Scientific research develops, as a native environment, knowledge. This environment consists of two interdependent divisions: theory and technology. First division occurs as a recursive research, while the second one becomes an application of the research activity. Over time, theories integrate methodologies and technology extends as infrastructure. The engine of this environment is learning, as the human activity of knowledge work. The threshold term of this model is the concepts map; it is based on Bloom’ taxonomy for the cognitive domain and highlights the notion of software scaffolding which is grounded in Vygotsky’s Social Development Theory with its major theme, Zone of Proximal Development. This article is designed as a conceptual paper, which analyzes specific structures of this type of educational research: the model reflects a foundation for a theory and finally, the theory evolves as groundwork for a system. The outcomes of this kind of approach are the examples, which are, theoretically, learning outcomes, and practically exist as educational objects, so-called e-learning.

  7. Junta de soldadura disímil de la aleación hk – 40 y del hierro fundido 24//Dissimilar welding joints of the alloy hk - 40 and of the cast iron 24

    Tomás Fernández‐Columbié

    2014-05-01

    Full Text Available El objetivo del trabajo es establecer el comportamiento microestructural de una unión soldada disímil en una aleación HK 40 y el hierro fundido 24, la cual se realiza en equipo que prestan servicios en la industria del níquel y que por las características de la unión, surgen en el mismo problema de agrietamiento. Se realizó una caracterización química de ambas aleaciones, luego por el proceso demecanizado se prepararon un total de nueve muestras, las que fueron soldada por proceso manual por arco eléctrico, los electrodos revestidos empleados fueron el E 312–16, el UTP 65 y el Castell Xiron 244, demostrándose en el análisis microestructural y en el diagrama de Schaeffler, que la disposición de la unión con el electrodo E 312–16 provoca la aparición de estructura interdendritica con origen a la fundición blanca, siendo más favorable la unión con el electrodo UTP 65. Se le realizó el análisis de microdureza en cada unión.Palabras claves: disímil, aleación, agrietamiento, soldadura, electrodos._____________________________________________________________________________AbstractIt is paper have the objective to establish the behaviour microstructure of an union welded dissimilar in an alloy HK 40 and the cast iron 24, which is carried out in team that you lend services in the industry of the nickel and that for the characteristics of the union, they arise in the same cracking problem. He was carried out a chemical characterization of both alloys, then for the process ofautomated got ready a total of nine samples, those that were welding for process shield for electric arch (SMAW, the electrodes lined employees were the E 312 - 16, the UTP 65 and the Castell Xiron 244, being demonstrated in the analysis microstructure and in the diagram of Schaeffler that the disposition of the union with the electrode E 312 - 16 cause the appearance of structure inter dendritewith origin to the white foundry, being more available the union

  8. Blended Learning

    Van der Baaren, John

    2009-01-01

    Van der Baaren, J. (2009). Blended Learning. Presentation given at the Mini symposium 'Blended Learning the way to go?'. November, 5, 2009, The Hague, The Netherlands: Netherlands Defence Academy (NDLA).

  9. Interface learning

    Thorhauge, Sally

    2014-01-01

    "Interface learning - New goals for museum and upper secondary school collaboration" investigates and analyzes the learning that takes place when museums and upper secondary schools in Denmark work together in local partnerships to develop and carry out school-related, museum-based coursework...... for students. The research focuses on the learning that the students experience in the interface of the two learning environments: The formal learning environment of the upper secondary school and the informal learning environment of the museum. Focus is also on the learning that the teachers and museum...... professionals experience as a result of their collaboration. The dissertation demonstrates how a given partnership’s collaboration affects the students’ learning experiences when they are doing the coursework. The dissertation presents findings that museum-school partnerships can use in order to develop...

  10. Learning Disabilities

    ... books. While his friends were meeting for pickup soccer games after school, he was back home in ... sometimes thought to contribute to learning disabilities. Poor nutrition early in life also may lead to learning ...

  11. Workplace learning

    Warring, Niels

    2005-01-01

    In November 2004 the Research Consortium on workplace learning under Learning Lab Denmark arranged the international conference “Workplace Learning – from the learner’s perspective”. The conference’s aim was to bring together researchers from different countries and institutions to explore...... and discuss recent developments in our understanding of workplace and work-related learning. The conference had nearly 100 participants with 59 papers presented, and among these five have been selected for presentation is this Special Issue....

  12. Children's Learning

    Siegler, Robert S.

    2005-01-01

    A new field of children's learning is emerging. This new field differs from the old in recognizing that children's learning includes active as well as passive mechanisms and qualitative as well as quantitative changes. Children's learning involves substantial variability of representations and strategies within individual children as well as…

  13. Blended Learning

    Imbriale, Ryan

    2013-01-01

    Teachers always have been and always will be the essential element in the classroom. They can create magic inside four walls, but they have never been able to create learning environments outside the classroom like they can today, thanks to blended learning. Blended learning allows students and teachers to break free of the isolation of the…

  14. Transformative Learning

    Wang, Victor C. X.; Cranton, Patricia

    2011-01-01

    The theory of transformative learning has been explored by different theorists and scholars. However, few scholars have made an attempt to make a comparison between transformative learning and Confucianism or between transformative learning and andragogy. The authors of this article address these comparisons to develop new and different insights…

  15. Blended Learning

    Bauerová, Andrea

    2013-01-01

    This thesis is focused on a new approach of education called blended learning. The history and developement of Blended Learning is described in the first part. Then the methods and tools of Blended Learning are evaluated and compared to the traditional methods of education. At the final part an efficient developement of the educational programs is emphasized.

  16. Just Learning

    Larsen-Freeman, Diane

    2017-01-01

    In this "First Person Singular" essay, the author describes her education, teaching experience, and interest in understanding the learning of language. Anyone reading this essay will not be surprised to learn that the author's questions about language learning and optimal teaching methods were only met with further questions, and no…

  17. MIL-101(Cr)@GO for dispersive micro-solid-phase extraction of pharmaceutical residue in chicken breast used in microwave-assisted coupling with HPLC-MS/MS detection.

    Wang, Yudan; Dai, Xinpeng; He, Xi; Chen, Lin; Hou, Xiaohong

    2017-10-25

    In this work, MIL-101(Cr)@GO (Graphite Oxide) was synthesized using a hydrothermal synthesis method and was applied as a dispersive micro-solid-phase extraction (D-μ-SPE) sorbent for the efficient concentration of four residual drugs (metronidazole, MNZ; tinidazole, TNZ; chloramphenicol, CAP; sulfamethoxazole, SMX). Meanwhile, the extraction process was optimized by combining it with microwave-assisted extraction. Factors affecting the D-μ-SPE efficiency, such as selection of sorbent materials, pH of the sample solution, salting-out effect, amount of used material, extraction time, desorption solvent and desorption time, were studied. Under the optimal extraction conditions, the linearity ranged from 10 to 1000ngkg -1 and 1-100ngkg -1 (r 2 ≥0.9928) for the target analytes. The limits of detection were between 0.08 and 1.02ngkg -1 , and the limits of quantitation were between 0.26 and 3.40ngkg -1 . Additionally, the developed method also exhibited good precision (RSD≤2.5%), repeatability (RSD≤4.3%), high recoveries (88.9%-102.3%) and low matrix effects (78.2%-95.1%). The proposed method proved to be an efficient and reliable approach for the determination of the analytes. Finally, we successfully detected the four drugs in chicken breast. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Microestructura de una unión disímil AISI 321 y una aleación A 351 grado HK-40 obtenida mediante soldadura manual por arco eléctrico

    Reilis Fuentes-Guilarte

    2016-05-01

    Full Text Available El objetivo fue establecer el comportamiento microestructural de una unión disímil de acero inoxidable austenítico AISI 321 y de la aleación A 351 grado HK 40 obtenida por fundición mediante soldadura manual por arco eléctrico y electrodos revestidos del tipo E 309 L-16. La estructura ferrita–austeníta que se forma en la unión del acero con la aleación es resultado del elevado contenido de carbono de la segunda. La baja velocidad de enfriamiento del cordón de soldadura revela ausencia de discontinuidades en el retículo cristalino de la zona afectada térmicamente y atenúa la formación de carburos de cromo del tipo Cr23C6, que puede formar la aleación A 351 grado HK 40 durante la difusión del volumen de fracción en masa del cromo.

  19. Padrões para germinação, pureza, umidade e peso de mil sementes em análises de sementes de espécies florestais nativas do Rio Grande do Sul

    Fernanda de Oliveira Brüning

    2011-06-01

    Full Text Available O presente trabalho teve como objetivo propor padrões de confiabilidade, em relação à germinação, pureza, peso de mil sementes e grau de umidade das sementes, visando ao controle de qualidade das análises de sementes de espécies florestais. Para tanto, foram utilizados resultados de análises de sementes de espécies florestais em laboratório, a partir do ano de 1997 até 2007, obtidos dos arquivos do Laboratório de Análise de Sementes da Fundação Estadual de Pesquisa Agropecuária do Estado do Rio Grande do Sul. Os padrões de confiabilidade foram construídos com base em uma análise de normalidade dos dados e da utilização do critério do pseudossigma. Os limites se mostraram eficientes no estabelecimento do valor mínimo aceitável para que um lote de sementes seja comercializado, propondo que valores de germinação dentro dos limites de confiabilidade baixos devem ser descartados, pois não apresentam índices germinativos aceitáveis. 

  20. Learning Networks for Lifelong Learning

    Sloep, Peter

    2009-01-01

    Presentation in a seminar organized by Christopher Hoadley at Penn State University, October 2004.Contains general introduction into the Learning Network Programme and a demonstration of the Netlogo Simulation of a Learning Network.

  1. Learning organisations

    Sabina Jelenc Krašovec

    2000-12-01

    Full Text Available A vast array of economical, social, political, cultural and other factors influences the transformed role of learning and education in the society, as well as the functioning of local community and its social and communication patterns. The influences which are manifested as global problems can only be successfully solved on the level of local community. Analogously with the society in general, there is a great need of transforming a local community into a learning, flexible and interconnected environment which takes into account different interests, wishes and needs regarding learning and being active. The fundamental answer to changes is the strategy of lifelong learning and education which requires reorganisation of all walks of life (work, free time, family, mass media, culture, sport, education and transforming of organisations into learning organisations. With learning society based on networks of knowledge individuals are turning into learning individuals, and organisations into learning organisations; people who learn take the responsibility of their progress, learning denotes partnership among learning people, teachers, parents, employers and local community, so that they work together to achieve better results.

  2. Learning Opportunities for Group Learning

    Gil, Alfonso J.; Mataveli, Mara

    2017-01-01

    Purpose: This paper aims to analyse the impact of organizational learning culture and learning facilitators in group learning. Design/methodology/approach: This study was conducted using a survey method applied to a statistically representative sample of employees from Rioja wine companies in Spain. A model was tested using a structural equation…

  3. Mimetic Learning

    Christoph Wulf

    2008-03-01

    Full Text Available Mimetic learning, learning by imitation, constitutes one of the most important forms of learning. Mimetic learning does not, however, just denote mere imitation or copying: Rather, it is a process by which the act of relating to other persons and worlds in a mimetic way leads to an en-hancement of one’s own world view, action, and behaviour. Mimetic learning is productive; it is related to the body, and it establishes a connection between the individual and the world as well as other persons; it creates practical knowledge, which is what makes it constitutive of social, artistic, and practical action. Mimetic learning is cultural learning, and as such it is crucial to teaching and education (Wulf, 2004; 2005.

  4. Deep learning

    Goodfellow, Ian; Courville, Aaron

    2016-01-01

    Deep learning is a form of machine learning that enables computers to learn from experience and understand the world in terms of a hierarchy of concepts. Because the computer gathers knowledge from experience, there is no need for a human computer operator to formally specify all the knowledge that the computer needs. The hierarchy of concepts allows the computer to learn complicated concepts by building them out of simpler ones; a graph of these hierarchies would be many layers deep. This book introduces a broad range of topics in deep learning. The text offers mathematical and conceptual background, covering relevant concepts in linear algebra, probability theory and information theory, numerical computation, and machine learning. It describes deep learning techniques used by practitioners in industry, including deep feedforward networks, regularization, optimization algorithms, convolutional networks, sequence modeling, and practical methodology; and it surveys such applications as natural language proces...

  5. Experimental and molecular docking investigation on metal-organic framework MIL-101(Cr) as a sorbent for vortex assisted dispersive micro-solid-phase extraction of trace 5-nitroimidazole residues in environmental water samples prior to UPLC-MS/MS analysis.

    Lu, Nan; Wang, Ting; Zhao, Pan; Zhang, Lianjun; Lun, Xiaowen; Zhang, Xueli; Hou, Xiaohong

    2016-11-01

    In the presented work, metal-organic framework (MOF) material MIL-101(Cr) (MIL, Matérial Institute Lavoisier) was used as a sorbent for vortex assisted dispersive micro-solid-phase extraction (VA-D-μ-SPE) of trace amount of metronidazole (MNZ), ronidazole (RNZ), secnidazole (SNZ), dimetridazole (DMZ), tinidazole (TNZ), and ornidazole (ONZ) in different environmental water samples. Ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) was used to quantify the target analytes. The extraction conditions, including type of sorbents, amount of MIL-101(Cr), solution pH, extraction method, extraction time, effect of salt, and elution conditions were investigated. Upon the optimal conditions, the developed method showed an excellent extraction performance with the average recovery ranging from 75.2 to 98.8 %. Good sensitivity levels were achieved with the detection limits of 0.03∼0.06 μg/L and the quantitation limits of 0.09∼0.20 μg/L. The linear ranges were varied from 0.1 to 20 for SNZ and ONZ and from 0.2 to 40 μg/L for MNZ, RNZ, DMZ, and TNZ (r 2  > 0.992), and repeatability of the method was satisfactory with the relative standard deviations (RSD) extraction and determination of 5-nitroimidazoles (5-NDZs) in 12 real water samples, showing the positive findings of MNZ and TNZ ranging from 0.3 to 1.0 μg/L. Furthermore, molecular docking was applied to explain the molecular interactions and free binding energies between MIL-101(Cr) and 5-NDZs, providing a deep insight into the adsorption mechanism. The proposed method exhibited the advantages of simplicity, rapidly, less solvent consumption, ease of operation, higher sensitivity, and lower matrix effect. Graphical abstract Schematic diagram of the extraction process and molecular docking investigation.

  6. Learning Disabilities and ADHD

    ... of illnesses and disabilities Learning disabilities and ADHD Learning disabilities and ADHD Learning disabilities affect how you ... ADHD. Learning disabilities Attention deficit hyperactivity disorder (ADHD) Learning disabilities top Having a learning disability does not ...

  7. Informal learning.

    Callanan, Maureen; Cervantes, Christi; Loomis, Molly

    2011-11-01

    We consider research and theory relevant to the notion of informal learning. Beginning with historical and definitional issues, we argue that learning happens not just in schools or in school-aged children. Many theorists have contrasted informal learning with formal learning. Moving beyond this dichotomy, and away from a focus on where learning occurs, we discuss five dimensions of informal learning that are drawn from the literature: (1) non-didactive, (2) highly socially collaborative, (3) embedded in meaningful activity, (4) initiated by learner's interest or choice, and (5) removed from external assessment. We consider these dimensions in the context of four sample domains: learning a first language, learning about the mind and emotions within families and communities, learning about science in family conversations and museum settings, and workplace learning. Finally, we conclude by considering convergences and divergences across the different literatures and suggesting areas for future research. WIREs Cogni Sci 2011 2 646-655 DOI: 10.1002/wcs.143 For further resources related to this article, please visit the WIREs website. Copyright © 2011 John Wiley & Sons, Ltd.

  8. Machine Learning

    CERN. Geneva

    2017-01-01

    Machine learning, which builds on ideas in computer science, statistics, and optimization, focuses on developing algorithms to identify patterns and regularities in data, and using these learned patterns to make predictions on new observations. Boosted by its industrial and commercial applications, the field of machine learning is quickly evolving and expanding. Recent advances have seen great success in the realms of computer vision, natural language processing, and broadly in data science. Many of these techniques have already been applied in particle physics, for instance for particle identification, detector monitoring, and the optimization of computer resources. Modern machine learning approaches, such as deep learning, are only just beginning to be applied to the analysis of High Energy Physics data to approach more and more complex problems. These classes will review the framework behind machine learning and discuss recent developments in the field.

  9. Doing learning

    Mathiasen, John Bang; Koch, Christian

    2014-01-01

    Purpose: To investigate how learning occurs in a systems development project, using a company developing wind turbine control systems in collaboration with customers as case. Design/methodology/approach: Dewey’s approach to learning is used, emphasising reciprocity between the individual...... learning processes and that the interchanges between materiality and systems developers block the learning processes due to a customer with imprecise demands and unclear system specifications. In the four cases discussed, learning does occur however. Research limitations/implications: A qualitative study...... focusing on individual systems developers gives limited insight into whether the learning processes found would occur in other systems development processes. Practical implications: Managers should ensure that constitutive means, such as specifications, are available, and that they are sufficiently...

  10. Metric learning

    Bellet, Aurelien; Sebban, Marc

    2015-01-01

    Similarity between objects plays an important role in both human cognitive processes and artificial systems for recognition and categorization. How to appropriately measure such similarities for a given task is crucial to the performance of many machine learning, pattern recognition and data mining methods. This book is devoted to metric learning, a set of techniques to automatically learn similarity and distance functions from data that has attracted a lot of interest in machine learning and related fields in the past ten years. In this book, we provide a thorough review of the metric learnin

  11. Learning to learn in MOOCs

    Milligan, Sandra; Ringtved, Ulla Lunde

    This paper outlines one way of understanding what it is about learning in MOOCs that is so distinctive, and explores the implications for the design of MOOCs. It draws on an ongoing research study into the nature of learning in MOOCs at the University of Melbourne.......This paper outlines one way of understanding what it is about learning in MOOCs that is so distinctive, and explores the implications for the design of MOOCs. It draws on an ongoing research study into the nature of learning in MOOCs at the University of Melbourne....

  12. Learning Cultures

    Rasmussen, Lauge Baungaard

    1998-01-01

    the article present different concepts and modelsof learning. It discuss some strutural tendenciesof developing environmental management systemsand point out alternatives to increasing formalization of rules.......the article present different concepts and modelsof learning. It discuss some strutural tendenciesof developing environmental management systemsand point out alternatives to increasing formalization of rules....

  13. Blended learning

    Staugaard, Hans Jørgen

    2012-01-01

    Forsøg på at indkredse begrebet blended learning i forbindelse med forberedelsen af projekt FlexVid.......Forsøg på at indkredse begrebet blended learning i forbindelse med forberedelsen af projekt FlexVid....

  14. Reflective Learning

    dell

    The main intent of this study was to identify the impact of using learning log as a learning strategy on the academic performance of university students. Second year psychology students were included as subjects of this study. In the beginning of the study, the students were divided into two: experimental group (N = 60) and ...

  15. Perceptual learning.

    Seitz, Aaron R

    2017-07-10

    Perceptual learning refers to how experience can change the way we perceive sights, sounds, smells, tastes, and touch. Examples abound: music training improves our ability to discern tones; experience with food and wines can refine our pallet (and unfortunately more quickly empty our wallet), and with years of training radiologists learn to save lives by discerning subtle details of images that escape the notice of untrained viewers. We often take perceptual learning for granted, but it has a profound impact on how we perceive the world. In this Primer, I will explain how perceptual learning is transformative in guiding our perceptual processes, how research into perceptual learning provides insight into fundamental mechanisms of learning and brain processes, and how knowledge of perceptual learning can be used to develop more effective training approaches for those requiring expert perceptual skills or those in need of perceptual rehabilitation (such as individuals with poor vision). I will make a case that perceptual learning is ubiquitous, scientifically interesting, and has substantial practical utility to us all. Copyright © 2017. Published by Elsevier Ltd.

  16. Pervasive Learning

    Helms, Niels Henrik; Larsen, Lasse Juel

    2009-01-01

    , it is not a specific place where you can access scarce information. Pervasive or ubiquitous communication opens up for taking the organizing and design of learning landscapes a step further. Furthermore it calls for theoretical developments, which can open up for a deeper understanding of the relationship between...... emerging contexts, design of contexts and learning....

  17. Flipped Learning

    Holmboe, Peter; Hachmann, Roland

    I FLIPPED LEARNING – FLIP MED VIDEO kan du læse om, hvordan du som underviser kommer godt i gang med at implementere video i undervisning, der har afsæt i tankerne omkring flipped learning. Bogen indeholder fire dele: I Del 1 fokuserer vi på det metarefleksive i at tænke video ind i undervisningen...

  18. Flipped Learning

    Hachmann, Roland; Holmboe, Peter

    arbejde med faglige problemstillinger gennem problembaserede og undersøgende didaktiske designs. Flipped Learning er dermed andet og mere end at distribuere digitale materialer til eleverne forud for undervisning. Flipped Learning er i lige så høj grad et syn på, hvordan undervisning med digitale medier...

  19. Situating learning

    Ribeiro, Gustavo; Georg, Susse; Finchman, Rob

    2004-01-01

    This paper looks at learning experiences in South Africa and Thailand by highlighting the role of context and culture in the learning process. The authors are based at Danish and South African higher education institutions and have contributed to DUCED's TFS programme in the positions of overall...

  20. Embodied Learning

    Stolz, Steven A.

    2015-01-01

    This article argues that psychological discourse fails miserably to provide an account of learning that can explain how humans come to understand, particularly understanding that has been grasped meaningfully. Part of the problem with psychological approaches to learning is that they are disconnected from the integral role embodiment plays in how…

  1. Distance learning

    Katarina Pucelj

    2006-12-01

    Full Text Available I would like to underline the role and importance of knowledge, which is acquired by individuals as a result of a learning process and experience. I have established that a form of learning, such as distance learning definitely contributes to a higher learning quality and leads to innovative, dynamic and knowledgebased society. Knowledge and skills enable individuals to cope with and manage changes, solve problems and also create new knowledge. Traditional learning practices face new circumstances, new and modern technologies appear, which enable quick and quality-oriented knowledge implementation. The centre of learning process at distance learning is to increase the quality of life of citizens, their competitiveness on the workforce market and ensure higher economic growth. Intellectual capital is the one, which represents the biggest capital of each society and knowledge is the key factor for succes of everybody, who are fully aware of this. Flexibility, openness and willingness of people to follow new IT solutions form suitable environment for developing and deciding to take up distance learning.

  2. Legitimate Learning.

    Stevenson, John

    1997-01-01

    What is considered legitimate learning is culturally and contextually specific, depending on what values are involved. Different values are engaged depending on whether legitimate learning is considered transformation of the individual in relation to self, in relation to society, or in relation to the workplace. (SK)

  3. Machine Learning.

    Kirrane, Diane E.

    1990-01-01

    As scientists seek to develop machines that can "learn," that is, solve problems by imitating the human brain, a gold mine of information on the processes of human learning is being discovered, expert systems are being improved, and human-machine interactions are being enhanced. (SK)

  4. Blended Learning as Transformational Institutional Learning

    VanDerLinden, Kim

    2014-01-01

    This chapter reviews institutional approaches to blended learning and the ways in which institutions support faculty in the intentional redesign of courses to produce optimal learning. The chapter positions blended learning as a strategic opportunity to engage in organizational learning.

  5. "Learned Helplessness" or "Learned Incompetence"?

    Sergent, Justine; Lambert, Wallace E.

    Studies in the past have shown that reinforcements independent of the subjects actions may induce a feeling of helplessness. Most experiments on learned helplessness have led researchers to believe that uncontrollability (non-contingency of feedback upon response) was the determining feature of learned helplessness, although in most studies…

  6. Teacher learning as workplace learning

    Imants, J.; Van Veen, K.

    2010-01-01

    Against the background of increasing attention in teacher professional development programs for situating teacher learning in the workplace, an overview is given of what is known in general and in educational workplace learning literature on the characteristics and conditions of the workplace.

  7. Learning, Learning Organisations and the Global Enterprise

    Manikutty, Sankaran

    2009-01-01

    The steadily increasing degree of globalisation of enterprises implies development of many skills, among which the skills to learn are among the most important. Learning takes place at the individual level, but collective learning and organisational learning are also important. Learning styles of individuals are different and learning styles are…

  8. Can machine learning explain human learning?

    Vahdat, M.; Oneto, L.; Anguita, D.; Funk, M.; Rauterberg, G.W.M.

    2016-01-01

    Learning Analytics (LA) has a major interest in exploring and understanding the learning process of humans and, for this purpose, benefits from both Cognitive Science, which studies how humans learn, and Machine Learning, which studies how algorithms learn from data. Usually, Machine Learning is

  9. Metrication of MIL-HDBK-5C

    1980-08-01

    is presented here for the sake of unifor- appropriate Federal, Military, or SAE Aerospacemity and to emphasize certain principles of Material...Considerations. -The indicated for air melted steel heat treated to pro- AISI or SAE alloy steels contain, in addition to duce a quench structure...D6ACb D6ACc 1379 MPa -- AISI 8740 AISI 4140 AISI 4 3 40 b AISI 4340 c AISI 4 340 d AMS Gradesbe AMS Gradesce D6ACb 1,6ACc 1241 MPa AISI 4130 AISI 8735

  10. Digital Line Graphs (DLG) 2MIL

    Kansas Data Access and Support Center — The DLG data files derived from the 1:2,000,000-scale maps contain selected base categories of cartographic data in digital form. The data files are derived from the...

  11. Evaluation of learning materials

    Bundsgaard, Jeppe; Hansen, Thomas Illum

    2011-01-01

    This paper presents a holistic framework for evaluating learning materials and designs for learning. A holistic evaluation comprises investigations of the potential learning potential, the actualized learning potential, and the actual learning. Each aspect is explained and exemplified through...

  12. Learning Spaces

    Falmagne, Jean-Claude

    2011-01-01

    Learning spaces offer a rigorous mathematical foundation for practical systems of educational technology. Learning spaces generalize partially ordered sets and are special cases of knowledge spaces. The various structures are investigated from the standpoints of combinatorial properties and stochastic processes. Leaning spaces have become the essential structures to be used in assessing students' competence of various topics. A practical example is offered by ALEKS, a Web-based, artificially intelligent assessment and learning system in mathematics and other scholarly fields. At the heart of A

  13. Supportive Learning: Linear Learning and Collaborative Learning

    Lee, Bih Ni; Abdullah, Sopiah; Kiu, Su Na

    2016-01-01

    This is a conceptual paper which is trying to look at the educational technology is not limited to high technology. However, electronic educational technology, also known as e-learning, has become an important part of today's society, which consists of a wide variety of approaches to digitization, components and methods of delivery. In the…

  14. Learning to learn: self-managed learning

    Jesús Miranda Izquierdo

    2006-09-01

    Full Text Available Thi is article analyzes the potentialities and weaknesses that non directive Pedagogy presents, an example of the so called self managed pedagogy, whose postulates are good to analyze for the contributions that this position can make to the search of new ways of learning.

  15. Habitação de iniciativa pública em Luanda e Maputo: modelos de intervenção e impactos socioterritoriais no novo milénio

    Vanessa de Pacheco Melo

    2015-02-01

    Full Text Available No início do novo milénio, em pleno contexto global neoliberal, Luanda e Maputo assistem à consolidação de diferentes paradigmas de intervenção urbana, associados a determinados modelos habitacionais de iniciativa pública, evidenciando-se os condomínios em altura e a habitação de piso único de crescimento extensivo. Atendendo às especificidades contextuais dessas duas capitais lusófonas e a suas grandes desigualdades socioterritoriais, recorremos ao conceito de «direito à cidade» para, por meio da análise de quatro casos de estudo, refletir sobre a adequação das soluções adotadas no âmbito desses dois modelos habitacionais, para a redução dessas desigualdades, no que se refere: às condições de habitabilidade, ao acesso aos benefícios da urbanização e à participação e apropriação de uma vida urbana transformada. Nesse contexto, onclui-se que existe um desequilíbrio entre o investimento estatal e as reais necessidades da maioria da população, tendencialmente de baixos recursos, que limita o «direito à cidade», no que se refere ao acesso às condições de habitabilidade e aos benefícios da urbanização. Esta limitação verifica-se quer nos condomínios em altura, direcionados para uma população de média e alta renda, quer na habitação de piso único de crescimento extensivo, mais adaptada à classe de menores recursos e onde a apropriação é possibilitada em ambos os contextos. Nenhum dos casos engloba todos os direitos contemplados pelo «direito à cidade», mas Maputo apresenta um panorama mais favorável, em parte devido a uma maior abertura à descentralização e participação popular na tomada de decisões e partilha de responsabilidades.

  16. Machine Learning

    Chikkagoudar, Satish; Chatterjee, Samrat; Thomas, Dennis G.; Carroll, Thomas E.; Muller, George

    2017-04-21

    The absence of a robust and unified theory of cyber dynamics presents challenges and opportunities for using machine learning based data-driven approaches to further the understanding of the behavior of such complex systems. Analysts can also use machine learning approaches to gain operational insights. In order to be operationally beneficial, cybersecurity machine learning based models need to have the ability to: (1) represent a real-world system, (2) infer system properties, and (3) learn and adapt based on expert knowledge and observations. Probabilistic models and Probabilistic graphical models provide these necessary properties and are further explored in this chapter. Bayesian Networks and Hidden Markov Models are introduced as an example of a widely used data driven classification/modeling strategy.

  17. Learning Leadership

    Hertel, Frederik; Fast, Alf Michael

    2018-01-01

    Is leadership a result of inheritance or is it something one learns during formal learning in e.g. business schools? This is the essential question addressed in this article. The article is based on a case study involving a new leader in charge of a group of profession practitioners. The leader...... promotes his leadership as a profession comparable to the professions of practitioners. This promotion implies that leadership is something one can and probably must learn during formal learning. The practitioners on the other hand reject this comprehension of leadership and long for a fellow practitioner...... to lead the organization. While asked they are unable to describe how, where and when they think a practitioner develops leadership skills necessary for leading fellows. In the following we will start analysing the case in order to comprehend and discuss both the professional leaders and the practitioners...

  18. Group learning

    Pimentel, Ricardo; Noguira, Eloy Eros da Silva; Elkjær, Bente

    The article presents a study that aims at the apprehension of the group learning in a top management team composed by teachers in a Brazilian Waldorf school whose management is collective. After deciding to extend the school, they had problems recruiting teachers who were already trained based...... on the Steiner´s ideas, which created practical problems for conducting management activities. The research seeks to understand how that group of teachers collectively manage the school, facing the lack of resources, a significant heterogeneity in the relationships, and the conflicts and contradictions......, and they are interrelated to the group learning as the construction, maintenance and reconstruction of the intelligibility of practices. From this perspective, it can be said that learning is a practice and not an exceptional phenomenon. Building, maintaining and rebuilding the intelligibility is the group learning...

  19. Learning Disabilities

    ... NICHD) See all related organizations Publications Problemas de aprendizaje Order NINDS Publications Patient Organizations CHADD - Children and ... NICHD) See all related organizations Publications Problemas de aprendizaje Order NINDS Publications Definition Learning disabilities are disorders ...

  20. Reflective Learning

    dell

    The experimental group students used learning log on a weekly basis while the control group did not. ... The term “memory” in psychology usually denotes an interest in the retention ... activities that contribute to information being remembered.

  1. Interorganizational learning systems

    Hjalager, Anne-Mette

    1999-01-01

    The occurrence of organizational and interorganizational learning processes is not only the result of management endeavors. Industry structures and market related issues have substantial spill-over effects. The article reviews literature, and it establishes a learning model in which elements from...... organizational environments are included into a systematic conceptual framework. The model allows four types of learning to be identified: P-learning (professional/craft systems learning), T-learning (technology embedded learning), D-learning (dualistic learning systems, where part of the labor force is exclude...... from learning), and S-learning (learning in social networks or clans). The situation related to service industries illustrates the typology....

  2. Lifelong Learning

    Krogh, Lone; Jensen, Annie Aarup

    2010-01-01

    Master education for adults has become a strategy for Lifelong Learning among many well-educated people in Denmark. This type of master education is part of the ‘parallel education system' in Denmark. As one of the first Danish universities who offered this type of Master education, Aalborg...... the intended as well as the unintended effects (personal and professional) of the master education. The data have been gathered among graduates from a specific master education, Master in Learning Processes, and the paper will draw on results from a quantitative survey based on a questionnaire answered by 120...

  3. Learning SPARQL

    DuCharme, Bob

    2011-01-01

    Get hands-on experience with SPARQL, the RDF query language that's become a key component of the semantic web. With this concise book, you will learn how to use the latest version of this W3C standard to retrieve and manipulate the increasing amount of public and private data available via SPARQL endpoints. Several open source and commercial tools already support SPARQL, and this introduction gets you started right away. Begin with how to write and run simple SPARQL 1.1 queries, then dive into the language's powerful features and capabilities for manipulating the data you retrieve. Learn wha

  4. Deep Learning in Open Source Learning Streams

    Kjærgaard, Thomas

    2016-01-01

    This chapter presents research on deep learning in a digital learning environment and raises the question if digital instructional designs can catalyze deeper learning than traditional classroom teaching. As a theoretical point of departure the notion of ‘situated learning’ is utilized...... and contrasted to the notion of functionalistic learning in a digital context. The mechanism that enables deep learning in this context is ‘The Open Source Learning Stream’. ‘The Open Source Learning Stream’ is the notion of sharing ‘learning instances’ in a digital space (discussion board, Facebook group......, unistructural, multistructural or relational learning. The research concludes that ‘The Open Source Learning Stream’ can catalyze deep learning and that there are four types of ‘Open Source Learning streams’; individual/ asynchronous, individual/synchronous, shared/asynchronous and shared...

  5. Mastering machine learning with scikit-learn

    Hackeling, Gavin

    2014-01-01

    If you are a software developer who wants to learn how machine learning models work and how to apply them effectively, this book is for you. Familiarity with machine learning fundamentals and Python will be helpful, but is not essential.

  6. Classification and Weakly Supervised Pain Localization using Multiple Segment Representation.

    Sikka, Karan; Dhall, Abhinav; Bartlett, Marian Stewart

    2014-10-01

    Automatic pain recognition from videos is a vital clinical application and, owing to its spontaneous nature, poses interesting challenges to automatic facial expression recognition (AFER) research. Previous pain vs no-pain systems have highlighted two major challenges: (1) ground truth is provided for the sequence, but the presence or absence of the target expression for a given frame is unknown, and (2) the time point and the duration of the pain expression event(s) in each video are unknown. To address these issues we propose a novel framework (referred to as MS-MIL) where each sequence is represented as a bag containing multiple segments, and multiple instance learning (MIL) is employed to handle this weakly labeled data in the form of sequence level ground-truth. These segments are generated via multiple clustering of a sequence or running a multi-scale temporal scanning window, and are represented using a state-of-the-art Bag of Words (BoW) representation. This work extends the idea of detecting facial expressions through 'concept frames' to 'concept segments' and argues through extensive experiments that algorithms such as MIL are needed to reap the benefits of such representation. The key advantages of our approach are: (1) joint detection and localization of painful frames using only sequence-level ground-truth, (2) incorporation of temporal dynamics by representing the data not as individual frames but as segments, and (3) extraction of multiple segments, which is well suited to signals with uncertain temporal location and duration in the video. Extensive experiments on UNBC-McMaster Shoulder Pain dataset highlight the effectiveness of the approach by achieving competitive results on both tasks of pain classification and localization in videos. We also empirically evaluate the contributions of different components of MS-MIL. The paper also includes the visualization of discriminative facial patches, important for pain detection, as discovered by our

  7. Transforming learning?

    1999-09-01

    A new Learning and Skills Council for post-16 learning is the latest proposal from the UK Government in its attempt to ensure a highly skilled workforce for the next century. Other aims will be to reduce the variability in standards of the existing post-16 system, coordination and coherence between further education and training, and a reduction in the duplication and layers in contracting and funding. The proposals include: a national Learning and Skills Council, with 40-50 local Learning and Skills Councils to develop local plans; a strengthened strategic role for business in education and training, influencing a budget of #5bn a radical new youth programme entitled `Connexions', with dedicated personal advisors for young people; greater cooperation between sixth forms and colleges; and the establishment of an independent inspectorate covering all work-related learning and training, to include a new role for Ofsted in inspecting the provision for 16-19 year-olds in schools and colleges. It is hoped that this programme will build on the successes of the previous systems and that savings of at least #50m can be achieved through streamlining and the reduction in bureaucracy. The intentions are set out in a White Paper, Learning to Succeed, which is available from the Stationery Office and bookshops, as well as on the website www.dfee.gov.uk/post16. Published in addition to the White Paper was `School Sixth form funding: a consultation paper' (available from DfEE publications, Prolog, PO Box 5050, Sherwood Park, Annesley, Nottingham NG15 0DJ) and `Transition plan for the post-16 education and training and for local delivery of support for small firms' (available from Trevor Tucknutt, TECSOP Division, Level 3, Department for Education and Employment, Moorfoot, Sheffield S1 4PQ). The deadline for comments on both the sixth form consultation document and the White Paper is 15 October 1999. Almost simultaneously with the announcement of the above proposals came the

  8. Deepening Learning through Learning-by-Inventing

    Apiola, Mikko; Tedre, Matti

    2013-01-01

    It has been shown that deep approaches to learning, intrinsic motivation, and self-regulated learning have strong positive effects on learning. How those pedagogical theories can be integrated in computing curricula is, however, still lacking empirically grounded analyses. This study integrated, in a robotics-based programming class, a method of learning-by-inventing, and studied its qualitative effects on students’ learning through 144 interviews. Five findings were related with learning the...

  9. Learning and Behavior

    ... List About PPMD Events News Login By Area Learning & Behavior Attention, Listening & Learning Autism Spectrum Disorder (ASD) ... Care Guidelines ❯ By Area ❯ Learning & Behavior Share Print Learning & Behavior Facts to Remember People with Duchenne may ...

  10. Learning via Query Synthesis

    Alabdulmohsin, Ibrahim

    2017-01-01

    Active learning is a subfield of machine learning that has been successfully used in many applications. One of the main branches of active learning is query synthe- sis, where the learning agent constructs artificial queries from scratch in order

  11. Managing Learning for Performance.

    Kuchinke, K. Peter

    1995-01-01

    Presents findings of organizational learning literature that could substantiate claims of learning organization proponents. Examines four learning processes and their contribution to performance-based learning management: knowledge acquisition, information distribution, information interpretation, and organizational memory. (SK)

  12. Learning Object Repositories

    Lehman, Rosemary

    2007-01-01

    This chapter looks at the development and nature of learning objects, meta-tagging standards and taxonomies, learning object repositories, learning object repository characteristics, and types of learning object repositories, with type examples. (Contains 1 table.)

  13. Blocking in Category Learning

    Bott, Lewis; Hoffman, Aaron B.; Murphy, Gregory L.

    2007-01-01

    Many theories of category learning assume that learning is driven by a need to minimize classification error. When there is no classification error, therefore, learning of individual features should be negligible. We tested this hypothesis by conducting three category learning experiments adapted from an associative learning blocking paradigm. Contrary to an error-driven account of learning, participants learned a wide range of information when they learned about categories, and blocking effe...

  14. Learned Helplessness

    Hooker, Carol E.

    1976-01-01

    Learned helplessness--the belief that a person's actions have no influence on the outcome of an event--is similar in many respects to the crisis state and depression. The author shows how this impaired social and psychological functioning occurs and identifies techniques that the social worker can use to prevent it. (Author)

  15. Learning Disabilities.

    Neuwirth, Sharyn

    This booklet uses hypothetical case examples to illustrate the definition, causal theories, and specific types of learning disabilities (LD). The cognitive and language performance of students with LD is compared to standard developmental milestones, and common approaches to the identification and education of children with LD are outlined.…

  16. Learning Together

    Kaufman, Sherry

    2014-01-01

    In spring 2012, Sherry Kaufman, a consultant at Francis W. Parker School in Chicago, was asked to support kindergarten teachers in deepening their practice of constructivism and exploring the Reggio Emilia approach to early childhood education. Central to such an approach is the belief that all learning is socially constructed through interaction…

  17. Learning Mongoid

    Rege, Gautam

    2013-01-01

    A step-by-step tutorial with focused examples that will help you build scalable, high performance Rails web applications with Mongoid.If you are an application developer who wants to learn how to use Mongoid in a Rails application, this book will be great for you. You are expected to be familiar with MongoDB and Ruby.

  18. Learning Lichens

    Thorne, Sarah

    2017-01-01

    The lichen is an ideal subject for student study because it is omnipresent in school yards, easily collected and observed year-round, a pioneer of evolution on land, and a bioindicator of air pollution. After doing fieldwork on this unusual composite organism as an apprentice with a team of lichenologists, Sarah Thorne developed Learning Lichens.…

  19. Learning Ionic

    Ravulavaru, Arvind

    2015-01-01

    This book is intended for those who want to learn how to build hybrid mobile applications using Ionic. It is also ideal for people who want to explore theming for Ionic apps. Prior knowledge of AngularJS is essential to complete this book successfully.

  20. Supervised Learning

    Rokach, Lior; Maimon, Oded

    This chapter summarizes the fundamental aspects of supervised methods. The chapter provides an overview of concepts from various interrelated fields used in subsequent chapters. It presents basic definitions and arguments from the supervised machine learning literature and considers various issues, such as performance evaluation techniques and challenges for data mining tasks.

  1. Learning Analytics

    Erik Duval

    2012-06-01

    Full Text Available This paper provides a brief introduction to the domain of ‘learning analytics’. We first explain the background and idea behind the concept. Then we give a brief overview of current research issues. We briefly list some more controversial issues before concluding.

  2. Learning Ansible

    Mohaan, Madhurranjan

    2014-01-01

    If you want to learn how to use Ansible to automate an infrastructure, either from scratch or to augment your current tooling with Ansible, then this is the book for you. It has plenty of practical examples to help you get to grips with Ansible.

  3. Learning Physics

    Cohen, E.

    2005-01-01

    Full Text:The issue of Teaching physics vs Learning physics in our institutions of higher learning will be discussed. Physics is taught mainly by frontal lectures an old (and proven) method. The great advancements of the Information Age are introduced by exposing the students to vast amounts of computerized information and directing them to numerical problem solving by interacting with the computer. These modern methods have several drawbacks: 1. Students get the impression of easy material acquisition while in fact it becomes superficial. 2. There is little integration of topics that are taught in different courses. 3. Insufficient interest is built among undergraduate students to pursue studies that involve deeper thinking and independent research (namely, studies towards a doctoral degree). Learning physics is a formative process in the education of physicists, natural scientists and engineers. It must be based on discussions and exchange of ideas among the students, since understanding the studied material means being able to explain it to a colleague. Some universities in the US initiated programs of learning physics by creating an environment in which small groups of students are engaged in discussing material, jointly solving problems and jointly conducting simulated experiments. This is done under the supervision of a mentor. Suggestions for implementing this method in Israel will be discussed

  4. Influences of Formal Learning, Personal Learning Orientation, and Supportive Learning Environment on Informal Learning

    Choi, Woojae; Jacobs, Ronald L.

    2011-01-01

    While workplace learning includes formal and informal learning, the relationship between the two has been overlooked, because they have been viewed as separate entities. This study investigated the effects of formal learning, personal learning orientation, and supportive learning environment on informal learning among 203 middle managers in Korean…

  5. From learning objects to learning activities

    Dalsgaard, Christian

    2005-01-01

    This paper discusses and questions the current metadata standards for learning objects from a pedagogical point of view. From a social constructivist approach, the paper discusses how learning objects can support problem based, self-governed learning activities. In order to support this approach......, it is argued that it is necessary to focus on learning activities rather than on learning objects. Further, it is argued that descriptions of learning objectives and learning activities should be separated from learning objects. The paper presents a new conception of learning objects which supports problem...... based, self-governed activities. Further, a new way of thinking pedagogy into learning objects is introduced. It is argued that a lack of pedagogical thinking in learning objects is not solved through pedagogical metadata. Instead, the paper suggests the concept of references as an alternative...

  6. How we learn

    Illeris, Knud

    How We Learn, deals with the fundamental issues of the processes of learning, critically assessing different types of learning and obstacles to learning. It also considers a broad range of other important questions in relation to learning such as: modern research into learning and brain functions......, self-perception, motivation and competence development, teaching, intelligence and learning style, learning in relation to gender and life age. The book provides a comprehensive introduction to both traditional learning theory and the newest international research into learning processes, while...... at the same time being an innovative contribution to a new and more holistic understanding of learning including discussion on school-based learning, net-based learning, workplace learning and educational politics. How We Learn examines all the key factors that help to create a holistic understanding of what...

  7. Using Learning Games to Meet Learning Objectives

    Henriksen, Thomas Duus

    2013-01-01

    This paper addresses the question on how learning games can be used to meet with the different levels in Bloom’s and the SOLO taxonomy, which are commonly used for evaluating the learning outcome of educational activities. The paper discusses the quality of game-based learning outcomes based on a...... on a case study of the learning game 6Styles....

  8. Still to Learn from Vicarious Learning

    Mayes, J. T.

    2015-01-01

    The term "vicarious learning" was introduced in the 1960s by Bandura, who demonstrated how learning can occur through observing the behaviour of others. Such social learning is effective without the need for the observer to experience feedback directly. More than twenty years later a series of studies on vicarious learning was undertaken…

  9. Learning Effectiveness of a Strategic Learning Course

    Burchard, Melinda S.; Swerdzewski, Peter

    2009-01-01

    The effectiveness of a postsecondary strategic learning course for improving metacognitive awareness and regulation was evaluated through systematic program assessment. The course emphasized students' awareness of personal learning through the study of learning theory and through practical application of specific learning strategies. Students…

  10. Social Media and Seamless Learning: Lessons Learned

    Panke, Stefanie; Kohls, Christian; Gaiser, Birgit

    2017-01-01

    The paper discusses best practice approaches and metrics for evaluation that support seamless learning with social media. We draw upon the theoretical frameworks of social learning theory, transfer learning (bricolage), and educational design patterns to elaborate upon different ideas for ways in which social media can support seamless learning.…

  11. Deep Learning

    Jensen, Morten Bornø; Bahnsen, Chris Holmberg; Nasrollahi, Kamal

    2018-01-01

    I løbet af de sidste 10 år er kunstige neurale netværk gået fra at være en støvet, udstødt tekno-logi til at spille en hovedrolle i udviklingen af kunstig intelligens. Dette fænomen kaldes deep learning og er inspireret af hjernens opbygning.......I løbet af de sidste 10 år er kunstige neurale netværk gået fra at være en støvet, udstødt tekno-logi til at spille en hovedrolle i udviklingen af kunstig intelligens. Dette fænomen kaldes deep learning og er inspireret af hjernens opbygning....

  12. Learning Java

    Niemeyer, Patrick

    2005-01-01

    Version 5.0 of the Java 2 Standard Edition SDK is the most important upgrade since Java first appeared a decade ago. With Java 5.0, you'll not only find substantial changes in the platform, but to the language itself-something that developers of Java took five years to complete. The main goal of Java 5.0 is to make it easier for you to develop safe, powerful code, but none of these improvements makes Java any easier to learn, even if you've programmed with Java for years. And that means our bestselling hands-on tutorial takes on even greater significance. Learning Java is the most widely sou

  13. Learning Raspbian

    Harrington, William

    2015-01-01

    This book is intended for developers who have worked with the Raspberry Pi and who want to learn how to make the most of the Raspbian operating system and their Raspberry Pi. Whether you are a beginner to the Raspberry Pi or a seasoned expert, this book will make you familiar with the Raspbian operating system and teach you how to get your Raspberry Pi up and running.

  14. Guided discovery learning in geometry learning

    Khasanah, V. N.; Usodo, B.; Subanti, S.

    2018-03-01

    Geometry is a part of the mathematics that must be learned in school. The purpose of this research was to determine the effect of Guided Discovery Learning (GDL) toward geometry learning achievement. This research had conducted at junior high school in Sukoharjo on academic years 2016/2017. Data collection was done based on student’s work test and documentation. Hypothesis testing used two ways analysis of variance (ANOVA) with unequal cells. The results of this research that GDL gave positive effect towards mathematics learning achievement. GDL gave better mathematics learning achievement than direct learning. There was no difference of mathematics learning achievement between male and female. There was no an interaction between sex differences and learning models toward student’s mathematics learning achievement. GDL can be used to improve students’ mathematics learning achievement in geometry.

  15. Learning to Learn Together with CSCL Tools

    Schwarz, Baruch B.; de Groot, Reuma; Mavrikis, Manolis; Dragon, Toby

    2015-01-01

    In this paper, we identify "Learning to Learn Together" (L2L2) as a new and important educational goal. Our view of L2L2 is a substantial extension of "Learning to Learn" (L2L): L2L2 consists of learning to collaborate to successfully face L2L challenges. It is inseparable from L2L, as it emerges when individuals face problems…

  16. US-Vietnam Mil-Mil Relations: How to Elevate the Relationship

    2013-03-01

    heat, yet looking surprisingly cool as he gazed across the calm lagoon of Cam Ranh Bay, and addressed the mostly civilian crew of the ship: Today I...Washington’s interest in accounting, to the fullest extent possible, for thousands of U.S. service members who remained missing in Vietnam. Leading a...Defense Cooperation; and building on lynch-pin legacy issues such as MIA, Agent Orange/dioxin remediation and demining), the U.S. should do the

  17. Proposed MIL Standard and Handbook - Flying Qualities of Air Vehicles. Volume 2. Proposed MIL Handbook

    1982-11-01

    aft c.g. 1.0 1) heo, nedium , Viin to 0 ma. CO RRFFCR Chingesho 00 LO iTAI I Category C 3.4.1.1 Rel atnion in transonicI Transonic 0 SnOB )N 3.5...methods for dealing with lead/lag systems like those of Table 5; unfortunately, neither is physically very appeal - ing. And in each, there is an underlying...cable). A change in the damping ratio requirements would mean that either: a) we restrict unaugmented vehicles as well; this is not appealing 119 - -o

  18. Technology, Learning, and Individual Differences

    Bear, Anne A. Ghost

    2012-01-01

    The learning needs for adults that result from the constant increase in technology are rooted in the adult learning concepts of (a) andragogy, (b) self-directed learning, (c) learning-how-to-learn, (d) real-life learning, and (e) learning strategies. This study described the learning strategies that adults use in learning to engage in an online…

  19. Human Machine Learning Symbiosis

    Walsh, Kenneth R.; Hoque, Md Tamjidul; Williams, Kim H.

    2017-01-01

    Human Machine Learning Symbiosis is a cooperative system where both the human learner and the machine learner learn from each other to create an effective and efficient learning environment adapted to the needs of the human learner. Such a system can be used in online learning modules so that the modules adapt to each learner's learning state both…

  20. Machine-Learning Research

    Dietterich, Thomas G.

    1997-01-01

    Machine-learning research has been making great progress in many directions. This article summarizes four of these directions and discusses some current open problems. The four directions are (1) the improvement of classification accuracy by learning ensembles of classifiers, (2) methods for scaling up supervised learning algorithms, (3) reinforcement learning, and (4) the learning of complex stochastic models.

  1. Targeted Learning

    van der Laan, Mark J

    2011-01-01

    The statistics profession is at a unique point in history. The need for valid statistical tools is greater than ever; data sets are massive, often measuring hundreds of thousands of measurements for a single subject. The field is ready to move towards clear objective benchmarks under which tools can be evaluated. Targeted learning allows (1) the full generalization and utilization of cross-validation as an estimator selection tool so that the subjective choices made by humans are now made by the machine, and (2) targeting the fitting of the probability distribution of the data toward the targe

  2. Learning Vaadin

    Frankel, Nicolas

    2011-01-01

    This book begins with a tutorial on Vaadin 7, followed by a process of planning, analyzing, building, and deploying a fully functional RIA while covering troubleshooting details along the way, making it an invaluable resource for answers to all your Vaadin questions. If you are a Java developer with some experience in Java web development and want to enter the world of Rich Internet Applications this technology and book are ideal for you. Learning Vaadin will be perfect as your next step towards building eye-candy dynamic web applications on a Java-based platform.

  3. Learning Cypher

    Panzarino, Onofrio

    2014-01-01

    An easy-to-follow guide full of tips and examples of real-world applications. In each chapter, a thorough example will show you the concepts in action, followed by a detailed explanation.This book is intended for those who want to learn how to create, query, and maintain a graph database, or who want to migrate to a graph database from SQL. It would be helpful to have some familiarity with Java and/or SQL, but no prior experience is required.

  4. Learning Perl

    Schwartz, Randal; Phoenix, Tom

    2011-01-01

    If you're just getting started with Perl, this is the book you want-whether you're a programmer, system administrator, or web hacker. Nicknamed "the Llama" by two generations of users, this bestseller closely follows the popular introductory Perl course taught by the authors since 1991. This 6th edition covers recent changes to the language up to version 5.14. Perl is suitable for almost any task on almost any platform, from short fixes to complete web applications. Learning Perl teaches you the basics and shows you how to write programs up to 128 lines long-roughly the size of 90% of the Pe

  5. Learning scikit-learn machine learning in Python

    Garreta, Raúl

    2013-01-01

    The book adopts a tutorial-based approach to introduce the user to Scikit-learn.If you are a programmer who wants to explore machine learning and data-based methods to build intelligent applications and enhance your programming skills, this the book for you. No previous experience with machine-learning algorithms is required.

  6. Automatic classification and detection of clinically relevant images for diabetic retinopathy

    Xu, Xinyu; Li, Baoxin

    2008-03-01

    We proposed a novel approach to automatic classification of Diabetic Retinopathy (DR) images and retrieval of clinically-relevant DR images from a database. Given a query image, our approach first classifies the image into one of the three categories: microaneurysm (MA), neovascularization (NV) and normal, and then it retrieves DR images that are clinically-relevant to the query image from an archival image database. In the classification stage, the query DR images are classified by the Multi-class Multiple-Instance Learning (McMIL) approach, where images are viewed as bags, each of which contains a number of instances corresponding to non-overlapping blocks, and each block is characterized by low-level features including color, texture, histogram of edge directions, and shape. McMIL first learns a collection of instance prototypes for each class that maximizes the Diverse Density function using Expectation- Maximization algorithm. A nonlinear mapping is then defined using the instance prototypes and maps every bag to a point in a new multi-class bag feature space. Finally a multi-class Support Vector Machine is trained in the multi-class bag feature space. In the retrieval stage, we retrieve images from the archival database who bear the same label with the query image, and who are the top K nearest neighbors of the query image in terms of similarity in the multi-class bag feature space. The classification approach achieves high classification accuracy, and the retrieval of clinically-relevant images not only facilitates utilization of the vast amount of hidden diagnostic knowledge in the database, but also improves the efficiency and accuracy of DR lesion diagnosis and assessment.

  7. Sustentabilidade na região metropolitana do Cariri – RMC: análise a partir dos objetivos de desenvolvimento do milênio – ODMs / Sustainability in the Cariri metropolitan region: analysis from the millennium development goals – MDGs

    Diego Coelho do Nascimento

    2016-12-01

    Full Text Available A Região Metropolitana do Cariri - RMC criada pela Lei Complementar Nº 78 de 2009, localiza-se ao Sul do estado do Ceará no Nordeste brasileiro e é constituída pelos municípios de Juazeiro do Norte, Crato, Barbalha, Jardim, Missão Velha, Caririaçu, Farias Brito, Nova Olinda e Santana do Cariri. A região atravessa uma acentuada fase de crescimento econômico e demográfico, e, consequentemente, de mudanças sociais e ambientais. O objetivo geral dessa pesquisa foi o de identificar o panorama da Região Metropolitana do Cariri no que diz respeito às dimensões componentes do desenvolvimento sustentável a partir da análise dos Objetivos de Desenvolvimento do Milênio na esfera municipal. A pesquisa possui foco quali-quantitativo, constituindo-se em um Estudo de Caso realizado por meio de pesquisa bibliográfica e documental. A coleta de dados se realizou por meio da análise dos Objetivos de Desenvolvimento do Milênio no âmbito dos municípios da RMC. Por meio da análise dos resultados, notou-se que a prosperidade econômica nessa região (sobretudo, no CRAJUBAR contrasta com a vulnerabilidade social e ambiental, produzindo um ambiente insustentável a médio e longo prazo.

  8. Technology Enhanced Learning

    Klemke, Roland; Specht, Marcus

    2013-01-01

    Klemke, R., & Specht, M. (2013, 26-27 September). Technology Enhanced Learning. Presentation at the fourth international conference on eLearning (eLearning 2013), Belgrade, Serbia. http://econference.metropolitan.ac.rs/

  9. Mobile Inquiry Based Learning

    Specht, Marcus

    2012-01-01

    Specht, M. (2012, 8 November). Mobile Inquiry Based Learning. Presentation given at the Workshop "Mobile inquiry-based learning" at the Mobile Learning Day 2012 at the Fernuniversität Hagen, Hagen, Germany.

  10. Learning and Memory

    1999-01-01

    Under various circumstances and in different species the outward expression of learning varies considerably, and this has led to the classification of different categories of learning. Just as there is no generally agreed on definition of learning, there is no one system of classification. Types of learning commonly recognized are: Habituation, sensitization, classical conditioning, operant conditioning, trial and error, taste aversion, latent learning, cultural learning, imprinting, insight ...

  11. Toward Learning Teams

    Hoda, Rashina; Babb, Jeff; Nørbjerg, Jacob

    2013-01-01

    to sacrifice learning-focused practices. Effective learning under pressure involves conscious efforts to implement original agile practices such as retrospectives and adapted strategies such as learning spikes. Teams, their management, and customers must all recognize the importance of creating learning teams......Today's software development challenges require learning teams that can continuously apply new engineering and management practices, new and complex technical skills, cross-functional skills, and experiential lessons learned. The pressure of delivering working software often forces software teams...

  12. Greedy Deep Dictionary Learning

    Tariyal, Snigdha; Majumdar, Angshul; Singh, Richa; Vatsa, Mayank

    2016-01-01

    In this work we propose a new deep learning tool called deep dictionary learning. Multi-level dictionaries are learnt in a greedy fashion, one layer at a time. This requires solving a simple (shallow) dictionary learning problem, the solution to this is well known. We apply the proposed technique on some benchmark deep learning datasets. We compare our results with other deep learning tools like stacked autoencoder and deep belief network; and state of the art supervised dictionary learning t...

  13. Learning Networks for Professional Development & Lifelong Learning

    Sloep, Peter

    2009-01-01

    Sloep, P. B. (2009). Learning Networks for Professional Development & Lifelong Learning. Presentation at a NeLLL seminar with Etienne Wenger held at the Open Universiteit Nederland. September, 10, 2009, Heerlen, The Netherlands.

  14. Use of blended learning in workplace learning

    Georgsen, Marianne; Løvstad, Charlotte Vange

    2014-01-01

    -based teaching materials. This paper presents the experiences of this particular project, and goes on to discuss the following points: • The blended learning design – use of IT for teaching, learning and communication • Digital learning materials – principals of design and use • Work place learning and learning......In 2014, a new system has been put in place for the inspection and approval of social welfare institutions in Denmark. In as little as 10 weeks, 330 new employees in five regional centres participated in an introductory course, designed as work place learning with extensive use of e-learning and IT...... from work – the interplay between experiences of the learner and the curriculum of the program •The approach taken to customising the e-learning design to the needs and demands of a particular case....

  15. Learning Design Development for Blended Learning

    Hansen, Janne Saltoft

    Learning design development for blended learning We started implementing Blackboard at Aarhus University in 2013. At the Health Faculty Blackboard replaced AULA which was a LMS with functionality for file distribution and only a vague focus on learning tools. Most teachers therefore had...... no experiences with blended leaning and technology supported out-of-class activities. At the pedagogical unit at the Health faculty we wanted to follow the Blackboard implementation with pedagogical tools for learning design to evolve the pedagogical use of the system. We needed to make development of blended...... learning courses easier for the teachers and also ensure quality in the courses. This poster describes the process from development of the learning design to implementation of the learning design at the faculty: 1. How to place demands on a learning design-model and how to develop and use such a model. 2...

  16. Judgments of Learning in Collaborative Learning Environments

    Helsdingen, Anne

    2010-01-01

    Helsdingen, A. S. (2010, March). Judgments of Learning in Collaborative Learning Environments. Poster presented at the 1st International Air Transport and Operations Symposium (ATOS 2010), Delft, The Netherlands: Delft University of Technology.

  17. Learning design guided learning analytics in MOOCs

    Brouns, Francis; Firssova, Olga

    2016-01-01

    Poster presentation for our paper Brouns, F., & Firssova, O. (2016, October).The role of learning design and learning analytics in MOOCs. Paper presented at 9th EDEN Research Workshop, Oldenburg, Germany.

  18. Networked professional learning

    Sloep, Peter

    2013-01-01

    Sloep, P. B. (2013). Networked professional learning. In A. Littlejohn, & A. Margaryan (Eds.), Technology-enhanced Professional Learning: Processes, Practices and Tools (pp. 97–108). London: Routledge.

  19. Resonant learning

    Lindvang, Charlotte

    2013-01-01

    -experience and personal therapy in training, first and foremost from the students’ perspective. The author focuses on presenting the qualitative part of her research which namely addresses the students’ experiences. Semi-structured qualitative interviews and qualitative music analyses were conducted, using a hermeneutic...... approach. The informants were nine music therapy students from Aalborg University, enrolled in the fifth year of their Master’s degree training programme. They were asked to bring a recording of an improvisation of their own choice to the interview. The qualitative data collection of text and music......The article presents a part of the authors PhD-study in music therapy about self-experiential training and the development of music therapeutic competencies. One of the purposes of the study was to explore and generate understanding and insight into the phenomena of learning through self...

  20. Blended Learning: An Innovative Approach

    Lalima; Dangwal, Kiran Lata

    2017-01-01

    Blended learning is an innovative concept that embraces the advantages of both traditional teaching in the classroom and ICT supported learning including both offline learning and online learning. It has scope for collaborative learning; constructive learning and computer assisted learning (CAI). Blended learning needs rigorous efforts, right…

  1. Brain Research: Implications for Learning.

    Soares, Louise M.; Soares, Anthony T.

    Brain research has illuminated several areas of the learning process: (1) learning as association; (2) learning as reinforcement; (3) learning as perception; (4) learning as imitation; (5) learning as organization; (6) learning as individual style; and (7) learning as brain activity. The classic conditioning model developed by Pavlov advanced…

  2. Blended Learning in Personalized Assistive Learning Environments

    Marinagi, Catherine; Skourlas, Christos

    2013-01-01

    In this paper, the special needs/requirements of disabled students and cost-benefits for applying blended learning in Personalized Educational Learning Environments (PELE) in Higher Education are studied. The authors describe how blended learning can form an attractive and helpful framework for assisting Deaf and Hard-of-Hearing (D-HH) students to…

  3. LEARNING ABOUT LEARNING, A CONFERENCE REPORT.

    BRUNER, JEROME

    TO EXPLORE THE NATURE OF THE LEARNING PROCESS, THREE IMPORTANT PROBLEM AREAS WERE STUDIED. STUDIES IN THE FIRST AREA, ATTITUDINAL AND AFFECTIVE SKILLS, ARE CONCERNED WITH INDUCING A CHILD TO LEARN AND SUSTAINING HIS ATTENTION. STUDIES IN THE SECOND AREA, COGNITIVE SKILLS, SOUGHT TO DISCOVER WHETHER GENERAL IDEAS AND SKILLS CAN BE LEARNED IN SUCH A…

  4. When Learning Analytics Meets E-Learning

    Czerkawski, Betul C.

    2015-01-01

    While student data systems are nothing new and most educators have been dealing with student data for many years, learning analytics has emerged as a new concept to capture educational big data. Learning analytics is about better understanding of the learning and teaching process and interpreting student data to improve their success and learning…

  5. Learning Networks for Professional Development & Lifelong Learning

    Brouns, Francis; Sloep, Peter

    2009-01-01

    Brouns, F., & Sloep, P. B. (2009). Learning Networks for Professional Development & Lifelong Learning. Presentation of the Learning Network Programme for a Korean delegation of Chonnam National University and Dankook University (researchers dr. Jeeheon Ryu and dr. Minjeong Kim and a Group of PhD and

  6. Stimulating Deep Learning Using Active Learning Techniques

    Yew, Tee Meng; Dawood, Fauziah K. P.; a/p S. Narayansany, Kannaki; a/p Palaniappa Manickam, M. Kamala; Jen, Leong Siok; Hoay, Kuan Chin

    2016-01-01

    When students and teachers behave in ways that reinforce learning as a spectator sport, the result can often be a classroom and overall learning environment that is mostly limited to transmission of information and rote learning rather than deep approaches towards meaningful construction and application of knowledge. A group of college instructors…

  7. Learning Analytics for Networked Learning Models

    Joksimovic, Srecko; Hatala, Marek; Gaševic, Dragan

    2014-01-01

    Teaching and learning in networked settings has attracted significant attention recently. The central topic of networked learning research is human-human and human-information interactions occurring within a networked learning environment. The nature of these interactions is highly complex and usually requires a multi-dimensional approach to…

  8. Facilitating Learning Organizations. Making Learning Count.

    Marsick, Victoria J.; Watkins, Karen E.

    This book offers advice to facilitators and change agents who wish to build systems-level learning to create knowledge that can be used to gain a competitive advantage. Chapter 1 describes forces driving companies to build, sustain, and effectively use systems-level learning and presents and links a working definition of the learning organization…

  9. Online transfer learning with extreme learning machine

    Yin, Haibo; Yang, Yun-an

    2017-05-01

    In this paper, we propose a new transfer learning algorithm for online training. The proposed algorithm, which is called Online Transfer Extreme Learning Machine (OTELM), is based on Online Sequential Extreme Learning Machine (OSELM) while it introduces Semi-Supervised Extreme Learning Machine (SSELM) to transfer knowledge from the source to the target domain. With the manifold regularization, SSELM picks out instances from the source domain that are less relevant to those in the target domain to initialize the online training, so as to improve the classification performance. Experimental results demonstrate that the proposed OTELM can effectively use instances in the source domain to enhance the learning performance.

  10. Professional learning versus interprofessional learning

    Nielsen, Cathrine Sand

    2014-01-01

    to improve quality in the Danish healthcare system (1). Cooperation between patients and professionals is challenged when patients are transferred between department, hospitals or sectors (2). Sharing and developing knowledge inter-professionally and in particular across sectors is inadequate (3......, which is necessary for development of the future undergraduate health professional education programmes. The PhD project intends to generate knowledge of: - the contributions of InterTværs to the quality of future health professional education programmes and to the future healthcare system....... The transition challenges in the healthcare system do not seem to only affect patients and knowledge, but also the students and learning. References: (1) Institute for Quality and Accreditation in Healthcare. 2012. The Danish Healthcare Quality Programme. Accreditation Standards for Hospitals (2) Siemsen IMD...

  11. When does social learning become cultural learning?

    Heyes, Cecilia

    2017-03-01

    Developmental research on selective social learning, or 'social learning strategies', is currently a rich source of information about when children copy behaviour, and who they prefer to copy. It also has the potential to tell us when and how human social learning becomes cultural learning; i.e. mediated by psychological mechanisms that are specialized, genetically or culturally, to promote cultural inheritance. However, this review article argues that, to realize its potential, research on the development of selective social learning needs more clearly to distinguish functional from mechanistic explanation; to achieve integration with research on attention and learning in adult humans and 'dumb' animals; and to recognize that psychological mechanisms can be specialized, not only by genetic evolution, but also by associative learning and cultural evolution. © 2015 John Wiley & Sons Ltd.

  12. Records for learning

    Binder, Thomas

    2005-01-01

    The article present and discuss findings from a participatory development of new learning practices among intensive care nurses, with an emphasize on the role of place making in informal learning activities.......The article present and discuss findings from a participatory development of new learning practices among intensive care nurses, with an emphasize on the role of place making in informal learning activities....

  13. Mobile Learning Platform

    Annan, Nana Kofi; Ofori-Dwumfou, George; Falch, Morten

    2012-01-01

    on the first experiences gained by both teachers and students by asking the following questions: What are the perceptions of teachers on m-learning? What are the effects of m-learning on students? What does m-learning contribute to face-to-face teaching and learning? Questionnaires were administered...

  14. Students Engaged in Learning

    Ismail, Emad A.; Groccia, James E.

    2018-01-01

    Engaging students in learning is a basic principle of effective undergraduate education. Outcomes of engaging students include meaningful learning experiences and enhanced skills in all learning domains. This chapter reviews the influence of engaging students in different forms of active learning on cognitive, psychomotor, and affective skill…

  15. Cultural Learning Redux

    Tomasello, Michael

    2016-01-01

    M. Tomasello, A. Kruger, and H. Ratner (1993) proposed a theory of cultural learning comprising imitative learning, instructed learning, and collaborative learning. Empirical and theoretical advances in the past 20 years suggest modifications to the theory; for example, children do not just imitate but overimitate in order to identify and…

  16. Teaching for Deep Learning

    Smith, Tracy Wilson; Colby, Susan A.

    2007-01-01

    The authors have been engaged in research focused on students' depth of learning as well as teachers' efforts to foster deep learning. Findings from a study examining the teaching practices and student learning outcomes of sixty-four teachers in seventeen different states (Smith et al. 2005) indicated that most of the learning in these classrooms…

  17. Culture and Organizational Learning

    Cook, N.; Yanow, D.

    2011-01-01

    Traditionally, theories of organizational learning have taken one of two approaches that share a common characterization of learning but differ in focus. One approach focuses on learning by individuals in organizational contexts; the other, on individual learning as a model for organizational

  18. Active Learning Methods

    Zayapragassarazan, Z.; Kumar, Santosh

    2012-01-01

    Present generation students are primarily active learners with varied learning experiences and lecture courses may not suit all their learning needs. Effective learning involves providing students with a sense of progress and control over their own learning. This requires creating a situation where learners have a chance to try out or test their…

  19. Algorithms for Reinforcement Learning

    Szepesvari, Csaba

    2010-01-01

    Reinforcement learning is a learning paradigm concerned with learning to control a system so as to maximize a numerical performance measure that expresses a long-term objective. What distinguishes reinforcement learning from supervised learning is that only partial feedback is given to the learner about the learner's predictions. Further, the predictions may have long term effects through influencing the future state of the controlled system. Thus, time plays a special role. The goal in reinforcement learning is to develop efficient learning algorithms, as well as to understand the algorithms'

  20. Rethinking e-learning

    Bang, Jørgen; Dalsgaard, Christian

    2006-01-01

    “Technology alone does not deliver educational success. It only becomes valuable in education if learners and teachers can do something useful with it” (E-Learning: The Partnership Challenge, 2001, p. 24). This quotation could be used as a bon mot for this chapter. Our main goal is to rethink e-learning...... by shifting the focus of attention from learning resources (learning objects) to learning activities, which also implies a refocusing of the pedagogical discussion of the learning process.Firstly, we try to identify why e-learning has not been able to deliver the educational results as expected five years ago...

  1. Lessons Learned

    Amanda Phelan BNS, MSc, PhD

    2015-03-01

    Full Text Available The public health nurses’ scope of practice explicitly includes child protection within their role, which places them in a prime position to identify child protection concerns. This role compliments that of other professions and voluntary agenices who work with children. Public health nurses are in a privileged position as they form a relationship with the child’s parent(s/guardian(s and are able to see the child in its own environment, which many professionals cannot. Child protection in Ireland, while influenced by other countries, has progressed through a distinct pathway that streamlined protocols and procedures. However, despite the above serious failures have occurred in the Irish system, and inquiries over the past 20 years persistently present similar contributing factors, namely, the lack of standardized and comprehensive service responses. Moreover, poor practice is compounded by the lack of recognition of the various interactional processes taking place within and between the different agencies of child protection, leading to psychological barriers in communication. This article will explore the lessons learned for public health nurses practice in safeguarding children in the Republic of Ireland.

  2. Learning tinnitus

    van Hemmen, J. Leo

    Tinnitus, implying the perception of sound without the presence of any acoustical stimulus, is a chronic and serious problem for about 2% of the human population. In many cases, tinnitus is a pitch-like sensation associated with a hearing loss that confines the tinnitus frequency to an interval of the tonotopic axis. Even in patients with a normal audiogram the presence of tinnitus may be associated with damage of hair-cell function in this interval. It has been suggested that homeostatic regulation and, hence, increase of activity leads to the emergence of tinnitus. For patients with hearing loss, we present spike-timing-dependent Hebbian plasticity (STDP) in conjunction with homeostasis as a mechanism for ``learning'' tinnitus in a realistic neuronal network with tonotopically arranged synaptic excitation and inhibition. In so doing we use both dynamical scaling of the synaptic strengths and altering the resting potential of the cells. The corresponding simulations are robust to parameter changes. Understanding the mechanisms of tinnitus induction, such as here, may help improving therapy. Work done in collaboration with Julie Goulet and Michael Schneider. JLvH has been supported partially by BCCN - Munich.

  3. Learning after acquired brain injury. Learning the hard way

    Boosman, H.

    2015-01-01

    Background: When the brain has suffered damage, the learning process can be considerably disturbed. Brain damage can influence what is learned, but also how learning takes place. What patients can learn can be viewed in terms of ‘learning ability’ and how patients learn in terms of ‘learning style’.

  4. Interpretable Active Learning

    Phillips, Richard L.; Chang, Kyu Hyun; Friedler, Sorelle A.

    2017-01-01

    Active learning has long been a topic of study in machine learning. However, as increasingly complex and opaque models have become standard practice, the process of active learning, too, has become more opaque. There has been little investigation into interpreting what specific trends and patterns an active learning strategy may be exploring. This work expands on the Local Interpretable Model-agnostic Explanations framework (LIME) to provide explanations for active learning recommendations. W...

  5. e-Learning Mathematics

    Almanasreh, Hasan

    2017-01-01

    This study concerns the use of e-learning in the educational system shedding the light on its advantages and disadvantages, and analyzing its applicability either partially or totally. From mathematical perspectives, theories are developed to test the courses tendency to online transformation. This leads to a new trend of learning, the offline-online-offline learning (fnf-learning), it merges e-learning mode with the traditional orientation of education. The derivation of the new trend is bas...

  6. Learning Theories In Instructional Multimedia For English Learning

    Farani, Rizki

    2016-01-01

    Learning theory is the concept of human learning. This concept is one of the important components in instructional for learning, especially English learning. English subject becomes one of important subjects for students but learning English needs specific strategy since it is not our vernacular. Considering human learning process in English learning is expected to increase students' motivation to understand English better. Nowadays, the application of learning theories in English learning ha...

  7. Designing Learning Resources in Synchronous Learning Environments

    Christiansen, Rene B

    2015-01-01

    Computer-mediated Communication (CMC) and synchronous learning environments offer new solutions for teachers and students that transcend the singular one-way transmission of content knowledge from teacher to student. CMC makes it possible not only to teach computer mediated but also to design...... and create new learning resources targeted to a specific group of learners. This paper addresses the possibilities of designing learning resources within synchronous learning environments. The empirical basis is a cross-country study involving students and teachers in primary schools in three Nordic...... Countries (Denmark, Sweden and Norway). On the basis of these empirical studies a set of design examples is drawn with the purpose of showing how the design fulfills the dual purpose of functioning as a remote, synchronous learning environment and - using the learning materials used and recordings...

  8. Multimodal sequence learning.

    Kemény, Ferenc; Meier, Beat

    2016-02-01

    While sequence learning research models complex phenomena, previous studies have mostly focused on unimodal sequences. The goal of the current experiment is to put implicit sequence learning into a multimodal context: to test whether it can operate across different modalities. We used the Task Sequence Learning paradigm to test whether sequence learning varies across modalities, and whether participants are able to learn multimodal sequences. Our results show that implicit sequence learning is very similar regardless of the source modality. However, the presence of correlated task and response sequences was required for learning to take place. The experiment provides new evidence for implicit sequence learning of abstract conceptual representations. In general, the results suggest that correlated sequences are necessary for implicit sequence learning to occur. Moreover, they show that elements from different modalities can be automatically integrated into one unitary multimodal sequence. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Transformative learning spaces

    Maslo, Elina

    Despite rapid development of learning theory in general and language learning theory in particular in the last years, we still cannot provide an unequivocal answer on the question “why do individuals who presumably possess similar cognitive capacities for second language learning achieve such var......, Leo (2010). The ecology of language learning: Practice to theory, theory to practice. Procedia – Social and Behavioral Sciences. Elsevier......., social, personal, cultural, and historical world they live in (van Lier, 2000). People can learn when they discover possibilities for learning, which appear in this complex world – so called affordances (Gibson, 1979). This happens in the interaction between people and their environment on the basis...... to the different ways of interaction of cognitive, affective and social factors by different individuals. Learning stories, where multilingual individuals are telling about their subjective experiences in language learning in particular and learning in general, are constructed by using a special developed...

  10. Scikit-learn: Machine Learning in Python

    Pedregosa, Fabian; Varoquaux, Gaël; Gramfort, Alexandre; Michel, Vincent; Thirion, Bertrand; Grisel, Olivier; Blondel, Mathieu; Prettenhofer, Peter; Weiss, Ron; Dubourg, Vincent; Vanderplas, Jake; Passos, Alexandre; Cournapeau, David; Brucher, Matthieu; Perrot, Matthieu

    2011-01-01

    International audience; Scikit-learn is a Python module integrating a wide range of state-of-the-art machine learning algorithms for medium-scale supervised and unsupervised problems. This package focuses on bringing machine learning to non-specialists using a general-purpose high-level language. Emphasis is put on ease of use, performance, documentation, and API consistency. It has minimal dependencies and is distributed under the simplified BSD license, encouraging its use in both academic ...

  11. Scikit-learn: Machine Learning in Python

    Pedregosa, Fabian; Varoquaux, Gaël; Gramfort, Alexandre; Michel, Vincent; Thirion, Bertrand; Grisel, Olivier; Blondel, Mathieu; Louppe, Gilles; Prettenhofer, Peter; Weiss, Ron; Dubourg, Vincent; Vanderplas, Jake; Passos, Alexandre; Cournapeau, David; Brucher, Matthieu

    2012-01-01

    Scikit-learn is a Python module integrating a wide range of state-of-the-art machine learning algorithms for medium-scale supervised and unsupervised problems. This package focuses on bringing machine learning to non-specialists using a general-purpose high-level language. Emphasis is put on ease of use, performance, documentation, and API consistency. It has minimal dependencies and is distributed under the simplified BSD license, encouraging its use in both academic and commercial settings....

  12. Assessing learning at the workplace

    Evers, Arnoud

    2018-01-01

    • Defining learning at the workplace • Assessing learning at the workplace • Facilitating learning at the workplace: - Structure - Culture - Leadership - Personal factors • Conclusions • Discussion

  13. Mobile learning in medicine

    Serkan Güllüoüǧlu, Sabri

    2013-03-01

    This paper outlines the main infrastructure for implicating mobile learning in medicine and present a sample mobile learning application for medical learning within the framework of mobile learning systems. Mobile technology is developing nowadays. In this case it will be useful to develop different learning environments using these innovations in internet based distance education. M-learning makes the most of being on location, providing immediate access, being connected, and acknowledges learning that occurs beyond formal learning settings, in places such as the workplace, home, and outdoors. Central to m-learning is the principle that it is the learner who is mobile rather than the device used to deliver m learning. The integration of mobile technologies into training has made learning more accessible and portable. Mobile technologies make it possible for a learner to have access to a computer and subsequently learning material and activities; at any time and in any place. Mobile devices can include: mobile phone, personal digital assistants (PDAs), personal digital media players (eg iPods, MP3 players), portable digital media players, portable digital multimedia players. Mobile learning (m-learning) is particularly important in medical education, and the major users of mobile devices are in the field of medicine. The contexts and environment in which learning occurs necessitates m-learning. Medical students are placed in hospital/clinical settings very early in training and require access to course information and to record and reflect on their experiences while on the move. As a result of this paper, this paper strives to compare and contrast mobile learning with normal learning in medicine from various perspectives and give insights and advises into the essential characteristics of both for sustaining medical education.

  14. Pervasive Learning Environments

    Hundebøl, Jesper; Helms, Niels Henrik

    2006-01-01

    The potentials of pervasive communication in learning within industry and education are right now being explored through different R&D projects. This paper outlines the background for and the possible learning potentials in what we describe as pervasive learning environments (PLE). PLE?s differ...... from virtual learning environments (VLE) primarily because in PLE?s the learning content is very much related to the actual context in which the learner finds himself. Two local (Denmark) cases illustrate various aspects of pervasive learning. One is the eBag, a pervasive digital portfolio used...

  15. Transnational Learning Processes

    Nedergaard, Peter

    This paper analyses and compares the transnational learning processes in the employment field in the European Union and among the Nordic countries. Based theoretically on a social constructivist model of learning and methodologically on a questionnaire distributed to the relevant participants......, a number of hypotheses concerning transnational learning processes are tested. The paper closes with a number of suggestions regarding an optimal institutional setting for facilitating transnational learning processes.Key words: Transnational learning, Open Method of Coordination, Learning, Employment......, European Employment Strategy, European Union, Nordic countries....

  16. Learning to Innovate

    Mei, Maggie

    the relationship between organizational learning and innovation creation in an organizational context. Taking a nuanced view of organizational learning, the dissertation investigates how three different organizational learning processes could affect innovation creation at the firm level and project level...... to the understanding of managing organizational learning for innovation creation at firms. The three studies in this dissertation show how three prominent organizational learning processes impact on firms’ innovation performance. Furthermore, the studies in this dissertation emphasize that there are limitation...... and boundary conditions for different organizational learning processes....

  17. e-Learning for Lifelong Learning in Denmark

    Buhl, Mie; Andreasen, Lars Birch

    2010-01-01

    The chapter on 'e-Learning for Lifelong Learning in Denmark' is part of an international White Paper, focusing on educational systems, describing status and characteristics and highlighting specific cases of e-learning and of lifelong learning....

  18. Lessons Learned

    Dougan, A.D.; Blair, S.

    2006-01-01

    LLNL turned in 5 Declaration Line Items (DLI's) in 2006. Of these, one was declared completed. We made some changes to streamline our process from 2005, used less money, time and fewer team members. This report is a description of what changes we made in 2006 and what we learned. Many of our core review team had changed from last year, including our Laboratory Director, the Facility safety and security representatives, our Division Leader, and the OPSEC Committee Chair. We were able to hand out an AP Manual to some of them, and briefed all newcomers to the AP process. We first went to the OPSEC Committee and explained what the Additional Protocol process would be for 2006 and solicited their help in locating declarable projects. We utilized the 'three questions' from the AP meeting last year. LLNL has no single place to locate all projects at the laboratory. We talked to Resource Managers and key Managers in the Energy and Environment Directorate and in the Nonproliferation Homeland and International Security Directorate to find applicable projects. We also talked to the Principal Investigators who had projects last year. We reviewed a list of CRADA's and LDRD projects given to us by the Laboratory Site Office. Talking to the PI's proved difficult because of vacation or travel schedules. We were never able to locate one PI in town. Fortunately, collateral information allowed us to screen out his project. We had no problems in downloading new versions of the DWA and DDA. It was helpful for both Steve Blair and Arden Dougan to have write privileges. During the time we were working on the project, we had to tag-team the work to allow for travel and vacation schedules. We had some difficulty locating an 'activities block' in the software. This was mentioned as something we needed to fix from our 2005 declaration. Evidently the Activities Block has been removed from the current version of the software. We also had trouble finding the DLI Detail Report, which we included

  19. Stealth Learning: Unexpected Learning Opportunities through Games

    Sharp, Laura A.

    2012-01-01

    Educators across the country struggle to create engaging, motivating learning environments for their Net Gen students. These learners expect instant gratification that traditional lectures do not provide. This leaves educators searching for innovative ways to engage students in order to encourage learning. One solution is for educators to use…

  20. From E-learning to Blended Learning

    Hansen, Line Skov; Hansen, Ole

    2013-01-01

    . The project uses a ?capacity building strategy where new practice and skills are built through pedagogical interventions mostly designed as courses based on blended learning with a dialogue oriented and practice related team-work as an important part. Through this work the team learns how to use a specific...