bluuebunny/crossref_metadata_2025 huggingface dataset:
Unusual Foreign Body in Urinary Bladder: A Case Report
Authors: Paul Deb Prosad , Das Debasish , Iqbal Kazi Sohel
Published: July 2012

In the urinary tract, foreign body is most commonly found in the urinary bladder. It is commonly self-inflicted but can rarely be introduced by other person. Various types of foreign bodies have been reported, which includes infusion set, aluminum rod, gold chain, pearl, fish, pencil etc. Here we report a case of a 28-year young man who gave the history of forceful introduction of a long wire of mobile charger into the bladder by another person. It could not be removed by himself and by the local doctors. Then he was referred to Enam Medical College & Hospital and subsequently was removed by suprapubic cystostomy. DOI: http://dx.doi.org/10.3329/jemc.v1i1.11139J Enam Med Col 2011; 1(1): 41-42
Lupus Vulgaris Causing Nasal Destruction: Rare Presentation in Current Time
Authors: Uddin Md Rokon , Akhter Farzana , Shumon Ahmed Minhaz
Published: July 2012

A 42-years old lady reported with slowly progressive reddish lesions over the nose, followed by atrophy and ulceration for about 6 years. Clinical examination revealed atrophied, ulcerated, erythematous lesions over central face, forehead and neck destroying whole nose. Mantoux test resulted 16×18 mm on 48 hours observation. Histopathological examination of the lesion showed noncaseating grunuloma along with Langhans giant cells in the upper dermis surrounded by lymphocytes. The conclusive diagnosis was lupus vulgaris based on above findings. Six months therapy with INH 300 mg plus rifampicin 600 mg supplemented by initial 2 months ethambutol 1000 mg plus pyrazinamide 1500 mg daily resulted clean-looking perforation with healthy margin. DOI: http://dx.doi.org/10.3329/jemc.v1i1.11140J Enam Med Col 2011; 1(1): 43-45
Lipid Peroxidation and Antioxidant Status in Preeclampsia
Authors: Begum Rokeya
Published: July 2012

Background: Preeclampsia is the most common and major medical complication of pregnancy with a high incidence of maternal and foetal morbidity and mortality. During pregnancy abnormally increased lipid peroxidation and free radical formation as well as significantly decreased antioxidants production in maternal blood may lead to pathogenesis of preeclampsia. So, we designed this study as little information is known about lipid peroxidation and antioxidant level in preeclampsia.Objectives: To assess the serum malondialdehyde (MDA) level as a lipid peroxidation product and vitamin E (antioxidant) level in women with preeclampsia as well as in normal pregnancy and to compare the values.Materials and Methods: The study was conducted on 60 women aged from 25 to 35 years in the department of Biochemistry, Budi Kemuliaan Maternity Hospital (BKMH) in Jakarta during the period April to July 2004. Twenty were normal pregnant women and 20 were preeclamptic patients. For comparison age matched 20 apparently healthy nonpregnant women were included in the study. The study subjects were selected from outpatient department (OPD) of Obstetrics and Gynaecology of BKMH in Jakarta. Serum MDA (lipid peroxidation product) level was measured by thiobarbituric acid reactive substances assay (TBRAS) method and vitamin E was estimated spectroflurometrically. Data were analyzed by unpaired Students t test between the groups by using SPSS version 12.Results: The mean serum MDA levels were significantly higher in normal pregnancy and also in preeclampsia than that of nonpregnant control group women (p<0.001). Again the serum MDA levels were significantly higher in preeclampsia than that of normal pregnant women (p<0.001). The serum vitamin E levels were significantly lower in preeclampsia and also in normal pregnancy than that of nonpregnant control women (p<0.001). Moreover, the serum vitamin E levels were significantly lower in preeclampsia compared to that of normal pregnancy which was also statistically significant (p<0.001)Conclusion: As in preeclamptic group level of oxidation product is high and antioxidant level is low, it can be assumed that in preeclampsia, serum antioxidants are excessively utilized to counteract the cellular damage mediated by free radicals production and deficient antioxidants as well as increased lipid peroxidations may be the important factors in the pathogenesis of preeclampsia. DOI: http://dx.doi.org/10.3329/jemc.v1i2.11462 J Enam Med Col 2011; 1(2): 56-59
Putaminal and White Matter Necrosis due to Methanol Intoxication
Authors: Mohiuddin Ahmed
Published: July 2012

Not available DOI: http://dx.doi.org/10.3329/jemc.v1i2.11470
The Impact of Climate Change on the Emerging and Re-emerging Infectious Diseases: Global Perspective
Authors: Ahmed Iftikhar
Published: July 2012

Not available   DOI: http://dx.doi.org/10.3329/jemc.v1i2.11472
LC3-Associated Phagocytosis (LAP): Connections with Host Autophagy
Authors: Lai Shu-chin , Devenish Rodney J.
Published: July 2012

Autophagy is an intracellular degradative process with a number of roles, one of which can be the protection of eukaryotic cells from invading microbes. Microtubule-associated protein light-chain 3 (LC3) is a key autophagy-related protein that is recruited to the double-membrane autophagosome responsible for sequestering material intended for delivery to lysosomes. GFP-LC3 is widely used as a marker of autophagosome formation as denoted by the formation of green puncta when viewed by fluorescence microscopy. Recently, it has been demonstrated that LC3 can be recruited to other membranes including single-membrane phagosomes, in a process termed LC3-associated phagocytosis (LAP). Thus, the observation of green puncta in cells can no longer, by itself, be taken as evidence of autophagy. This review will clarify those features of LAP which serve to distinguish it from autophagy and that make connections with host autophagic responses in terms of infection by microbial pathogens. More specifically, it will refer to concurrent studies of the mechanism by which LAP is triggered in comparison to autophagy.
Exergy Analysis of Overspray Process in Gas Turbine Systems
Authors: Kim Kyoung Hoon , Kim Kyoungjin
Published: July 2012

Gas turbine power can be augmented by overspray process which consists of inlet fogging and wet compression. In this study exergy analysis of the overspray process in gas turbine system is carried out with a non-equilibrium analytical modeling based on droplet evaporation and the second law of thermodynamics. This work focuses on the effects of system parameters such as pressure ratio, water injection ratio, and initial droplet diameter on exergetical performances including irreversibility and exergy efficiency of the process. The process performances are also estimated under the condition of saturated water injection ratio above which complete evaporation of injected water droplets within a compressor is not possible. The results show that the irreversibility increases but the saturated irreversibility decreases with increasing initial droplet diameter for a specified pressure ratio.
Plasma Membranes Modified by Plasma Treatment or Deposition as Solid Electrolytes for Potential Application in Solid Alkaline Fuel Cells
Authors: Reinholdt Marc , Ilie Alina , Roualdès Stéphanie , Frugier Jérémy , Schieda Mauricio , Coutanceau Christophe , Martemianov Serguei , Flaud Valérie , Beche Eric , Durand Jean
Published: July 2012

In the highly competitive market of fuel cells, solid alkaline fuel cells using liquid fuel (such as cheap, non-toxic and non-valorized glycerol) and not requiring noble metal as catalyst seem quite promising. One of the main hurdles for emergence of such a technology is the development of a hydroxide-conducting membrane characterized by both high conductivity and low fuel permeability. Plasma treatments can enable to positively tune the main fuel cell membrane requirements. In this work, commercial ADP-Morgane® fluorinated polymer membranes and a new brand of cross-linked poly(aryl-ether) polymer membranes, named AMELI-32®, both containing quaternary ammonium functionalities, have been modified by argon plasma treatment or triallylamine-based plasma deposit. Under the concomitant etching/cross-linking/oxidation effects inherent to the plasma modification, transport properties (ionic exchange capacity, water uptake, ionic conductivity and fuel retention) of membranes have been improved. Consequently, using plasma modified ADP-Morgane® membrane as electrolyte in a solid alkaline fuel cell operating with glycerol as fuel has allowed increasing the maximum power density by a factor 3 when compared to the untreated membrane.
Acuminatol and Other Antioxidative Resveratrol Oligomers from the Stem Bark of Shorea acuminata
Authors: Muhammad Norhayati , Din Laily B. , Sahidin Idin , Hashim Siti Farah , Ibrahim Nazlina , Zakaria Zuriati , Yaacob Wan A.
Published: July 2012

A new resveratrol dimer, acuminatol (1), was isolated along with five known compounds from the acetone extract of the stem bark of Shorea acuminata. Their structures and stereochemistry were determined by spectroscopic methods, which included the extensive use of 2D NMR techniques. All isolated compounds were evaluated for their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (RSA) and the β-carotene-linoleic acid (BCLA) assays, and compared with those of the standards of ascorbic acid (AscA) and butylated hydroxytoluene (BHT). All compounds tested exhibited good to moderate antioxidant activity in the DPPH assay (IC50s 0.84 to 10.06 mM) and displayed strong inhibition of β-carotene oxidation (IC50s 0.10 to 0.22 mM). The isolated compounds were evaluated on the Vero cell line and were found to be non-cytotoxic with LC50 values between 161 to 830 µM.
Synthesis and Characterization of Cationic Glycidyl-Based Poly(aminoester)-Folic Acid Targeting Conjugates and Study on Gene Delivery
Authors: Tsai Pai Feng , Chang Wei Yang , Hsiao Yu Che , Li Kuo Jung , Shau Min Da
Published: July 2012

A new poly(aminoester) (EPAE-FA) containing folic acid and amino groups in the backbone and side chain was synthesized. EPAE-FA self-assembled readily with the plasmid DNA (pCMV-βgal) in HEPES buffer and was characterized by dynamic light scattering, zeta potential, fluorescence images, and XTT cell viability assays. To evaluate the transfection effect of graft ratio of FA on the EPAE system, EPAE-FA polymers with two different graft ratios (EPAE-FA12k and EPAE-FA14k) were also prepared. This study found that all EPAE-FA polymers were able to bind plasmid DNA and yielded positively charged complexes with nano-sized particles ( < 200 nm). To assess the transfection efficiency mediated by EPAE and EPAE-FA polymers, we performed in vitro transfection activity assays using FR-negative (COS-7) and FR-positive (HeLa) cells. The EPAE-FA12k/DNA and EPAE-FA14k/DNA complexes were able to transfect HeLa cell in vitro with higher transfection efficiency than PEI25k/DNA at the similar weight ratio. These results demonstrated that the introduction of FA into EPAE system had a significant effect on transferring ability for FR-positive cells (HeLa). Examination of the cytotoxicity of PEI25k and EPAE-FA system revealed that EPAE-FA system had lower cytotoxicity. In this paper, EPAE-FA seemed to be a novel cationic poly(aminoester) for gene delivery and an interesting candidate for further study.
Cellular Mechanisms of Zinc Dysregulation: A Perspective on Zinc Homeostasis as an Etiological Factor in the Development and Progression of Breast Cancer
Authors: Alam Samina , Kelleher Shannon L.
Published: July 2012

Worldwide, breast cancer is the most commonly diagnosed cancer among women and is the leading cause of female cancer deaths. Zinc (Zn) functions as an antioxidant and plays a role in maintaining genomic stability. Zn deficiency results in oxidative DNA damage and increased cancer risk. Studies suggest an inverse association between dietary and plasma Zn levels and the risk for developing breast cancer. In contrast, breast tumor biopsies display significantly higher Zn levels compared with normal tissue. Zn accumulation in tumor tissue also correlates with increased levels of Zn importing proteins. Further, aberrant expression of Zn transporters in tumors correlates with malignancy, suggesting that altered metal homeostasis in the breast could contribute to malignant transformation and the severity of cancer. However, studies have yet to link dysregulated Zn transport and abnormal Zn-dependent functions in breast cancer development. Herein, we summarize studies that address the multi-modal role of Zn dyshomeostasis in breast cancer with respect to the role of Zn in modulating oxidative stress, DNA damage response/repair pathways and cell proliferation/apoptosis, and the relationship to aberrant regulation of Zn transporters. We also compare Zn dysregulation in breast tissue to that of prostate, pancreatic and ovarian cancer where possible.
A Distributed Reasoning Engine Ecosystem for Semantic Context-Management in Smart Environments
Authors: Almeida Aitor , López-de-Ipiña Diego
Published: July 2012

To be able to react adequately a smart environment must be aware of the context and its changes. Modeling the context allows applications to better understand it and to adapt to its changes. In order to do this an appropriate formal representation method is needed. Ontologies have proven themselves to be one of the best tools to do it. Semantic inference provides a powerful framework to reason over the context data. But there are some problems with this approach. The inference over semantic context information can be cumbersome when working with a large amount of data. This situation has become more common in modern smart environments where there are a lot sensors and devices available. In order to tackle this problem we have developed a mechanism to distribute the context reasoning problem into smaller parts in order to reduce the inference time. In this paper we describe a distributed peer-to-peer agent architecture of context consumers and context providers. We explain how this inference sharing process works, partitioning the context information according to the interests of the agents, location and a certainty factor. We also discuss the system architecture, analyzing the negotiation process between the agents. Finally we compare the distributed reasoning with the centralized one, analyzing in which situations is more suitable each approach.
A Wireless Magnetic Resonance Energy Transfer System for Micro Implantable Medical Sensors
Authors: Li Xiuhan , Zhang Hanru , Peng Fei , Li Yang , Yang Tianyang , Wang Bo , Fang Dongming
Published: July 2012

Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of micro-implantable medical sensors. The entire system is composed of the in vitro part, including the energy transmitting circuit and resonant transmitter coils, and in vivo part, including the micro resonant receiver coils and signal shaping chip which includes the rectifier module and LDO voltage regulator module. Transmitter and receiver coils are wound by Litz wire, and the diameter of the receiver coils is just 1.9 cm. The energy transfer efficiency of the four-coil system is greatly improved compared to the conventional two-coil system. When the distance between the transmitter coils and the receiver coils is 1.5 cm, the transfer efficiency is 85% at the frequency of 742 kHz. The power transfer efficiency can be optimized by adding magnetic enhanced resonators. The receiving voltage signal is converted to a stable output voltage of 3.3 V and a current of 10 mA at the distance of 2 cm. In addition, the output current varies with changes in the distance. The whole implanted part is packaged with PDMS of excellent biocompatibility and the volume of it is about 1 cm3.
Réinventer l'école, réinventer l'administration
Authors: Aebischer Sylvie
Published: July 2012

Résumé Les prémices du discours managérial dans l’éducation sont bien antérieures à la LOLF et sont à rechercher en France dès les années 1980. La loi d’orientation pour l’éducation de 1989 dite loi Jospin est un moment clé de ce tournant politique, alors même qu’elle est généralement lue comme un texte essentiellement pédagogique. L’article éclaire le « moment réformateur » de 1989 à partir d’une scène trop peu étudiée en science politique : le travail d’élaboration de la loi au sein du cabinet ministériel. La prégnance de ce prisme managérial dans ce texte pédagogique s’explique d’abord par l’étude de ses producteurs et de leurs modes de travail. En réintégrant l’analyse des trajectoires des conseillers techniques à la sociologie de l’action publique, cet article montre le lien entre leur origine sociale, leur socialisation professionnelle, leur rapport au système éducatif et leur attachement à la « Réforme de l’État ».
Le Conseil national des programmes (1985-1994) : l'institutionnalisation chaotique d'une entreprise réformatrice
Authors: Clément Pierre
Published: July 2012

Résumé À la fin des années 1980, alors que la capacité mobilisatrice de la laïcité s’épuise et que la « démocratisation » semble dans l’impasse, le ministre de l’Éducation nationale, Lionel Jospin, initie un processus de rénovation des contenus d’enseignement. Créé en 1990, le Conseil national des programmes (CNP) a vocation à constituer la cheville ouvrière de cette entreprise réformatrice. À partir d’une enquête sur archives et par entretiens, cet article analyse les luttes de territoire bureaucratique entre les trois institutions – le CNP, l’Inspection générale et la direction des lycées et collèges – alors en conflit pour le monopole du pouvoir pédagogique. Il montre comment la codification progressive d’un nouveau modus vivendi institutionnel permet l’amorce d’une réforme en profondeur des programmes du second degré, dont le socle commun de connaissances et de compétences constitue l’aboutissement.
La création et la diffusion du « bac théâtre » : une offre scolaire promue « d'en bas »
Authors: Lemêtre Claire
Published: July 2012

Résumé En se centrant sur un des aspects méconnus de la réforme des filières du baccalauréat au moment de la seconde explosion scolaire, l’article met en évidence le rôle déterminant des enseignants dans la mise en œuvre des politiques éducatives et de l’offre de formation en particulier. À partir de l’exemple du « baccalauréat théâtre » et à l’appui d’une enquête ethnographique menée dans la région des Pays de la Loire, le texte montre que cette nouvelle offre scolaire n’est pas seulement promue « d’en haut » dans la mesure où son émergence doit au moins autant à la mobilisation d’enseignants singuliers inscrits dans les sphères militantes et culturelles. L’occasion est alors donnée de rappeler combien la réussite d’une action publique réside aussi dans ses usages et appropriations par les acteurs de terrain.
Participation électorale, pénétration de l'État et violence armée dans la crise politique turque de la seconde moitié des années 1970
Authors: Gourisse Benjamin
Published: July 2012

Résumé L’article se présente comme une contribution à l’analyse des situations de crises politiques prolongées caractérisées par la perte de capacité de l’État à exercer ses monopoles de violence physique et symbolique légitime. Il analyse la crise politique turque de la seconde moitié des années 1970, qui voit la diffusion de mobilisations radicales antagonistes et la routinisation de l’usage de la violence physique irrégulière, dans un contexte de délitement des monopoles étatiques. Il montre que cette configuration recouvre deux processus distincts mais liés, à savoir la modification des règles des jeux étatiques et de celles des jeux politiques, toutes deux provoquées par les activités tactiques d’un des protagonistes du conflit. Il s’agit alors d’analyser comment, en mettant en œuvre une stratégie d’accès au pouvoir reposant sur le triptyque participation électorale – pénétration de l’État – violence physique, le Mouvement nationaliste a contribué à la formation et à l’intensification des processus de crise.
Étude pilote pour l'évaluation des outils de gestion et de communication sociale (RSE) des grandes entreprises ibériques
Authors: Felipe-Fernández E. , André Jean-Marc , Casado-Cañeque F.
Published: July 2012

Résumé L’objectif principal de ce travail est de proposer une méthode pour l’élaboration d’un plan de communication sociale cohérent dans le domaine de la RSE. Ce travail s’intéresse à la vision et à la mission sociale de l’entreprise, à sa relation avec ses différentes parties prenantes et au suivi et à la mesure de ses impacts. Les travaux présentés ici s’inscrivent dans une démarche d’élaboration d’une méthodologie complète d’évaluation des outils de gestion et de communication sociale (RSE) des grandes entreprises ibériques. La première phase de l’outil méthodologique « comprendre la réalité de l’entreprise » y est développée. L’objet du présent travail est de présenter les principales propositions et conclusions à prendre en compte pour la réalisation de cette étape. Quatre phases principales de structuration sont définies : « l’histoire », « la philosophie », « les indicateurs » et « la perception ».
Complexité et incertitude : l'éthique managériale
Authors: Brun Gilles
Published: July 2012

Résumé La transformation normative du social et de l’intime génère une liberté individuelle qui recherche à s’orienter dans un environnement complexe et incertain où le conflit est devenu davantage émotionnel et interpersonnel, dans l’entreprise où une emprise psychique managériale tend à se développer. Entre médiation sociocognitive, adhésion à la visibilité continue, soumission, résistance, adhésion au désengagement de la personne au monde, le choix est vaste. La médiation sociocognitive devrait être la source d’une nouvelle inspiration éthique des entreprises et d’un gigantesque effort de repensée du management.
The human side of organisational change: improving appropriation of project evolutions
Authors: Perotti Clément , Minel Stéphanie , Roussel Benoît , Renaud Jean
Published: July 2012

Résumé Cet article traite du succès du changement organisationnel. Nous introduisons ces travaux empiriques par une illustration du problème industriel : comment structurer le changement organisationnel pour assurer une appropriation correcte de l’état futur souhaité. À partir d’une analyse de la littérature, nous proposons une vision où le changement organisationnel est supporté par un double processus d’appropriation : appropriation au niveau de l’ensemble de l’organisation d’une part, et appropriation par les individus d’autre part. Nous montrerons ensuite que le projet est un moyen valide de gérer le changement organisationnel et de structurer le processus d’appropriation global par l’entreprise. Dans l’optique de soutenir le processus d’appropriation de la nouveauté par les individus, nous avons développé une méthode d’accompagnement intégrée à la gestion du changement par projet. Nous proposons un phasage générique des actions d’accompagnement par rapport aux phases d’un projet, et aux processus d’appropriation du changement par l’organisation et les individus. À partir d’une étude de trois ans des projets d’un acteur majeur du secteur aéronautique en France, nous présenterons enfin les apports de notre méthode au niveau de l’appropriation organisationnelle et individuelle.
L'institution confrontée à l'enfermement et à l'ouverture
Authors: Amourous Charles
Published: July 2012

Résumé L’actualité et l’observation ordinaire nous révèlent des tensions antinomiques entre l’organisation de prestations en « milieu ouvert » et l’instauration d’institutions totalement fermées. Comment peut-on, aujourd’hui, créer des établissements enclos ? Est-ce un projet élaboré ou une réaction à des peurs, à des pressions sécuritaires ? Sait-on ce qu’est l’enfermement et tout son carcan ? En retour, connaît-on les effets de l’ouverture ? L’étude, dans la durée, des milieux d’asiles et d’hospices nous permet de répondre par une double démarche : d’une part pénétrer un milieu d’exclusion et d’enfermement, pour découvrir quelle vie y mènent les pensionnaires ; d’autre part repérer les effets de l’ouverture progressive de ce type d’institution. Ces démarches nous autorisent à une analyse comparative amplifiée d’une typologie mythique et anthropologique. Telle la nature, la culture a horreur du vide. Même exclus et enfermés, les hommes élaborent une vie sociale. Ce vivre-ensemble est marqué par le pouvoir des dominants violents qui cumulent autorité et avantages ; il y a une forme de concentration hiérarchique rigide. L’institution qui s’entrouvre, s’enrichit de mouvements et d’échanges. D’un système à voie unique et centripète, elle passe à un ensemble varié aux rôles et activités diversifiés. La porte grande ouverte permet à l’organisation d’accéder à une décentration qui rend possible une coopération (endogène et exogène) et une communauté plus large et plus polymorphe. Mythologie romaine et anthropologie permettent une typologie comparative qui souligne le très net appauvrissement d’un milieu enclos, l’enrichissement d’une unité entrouverte, l’épanouissement d’une institution qui arrive à partager son destin avec ses voisins. Les milieux de vie, quels qu’ils soient, méritent une approche mythique et anthropologique qui permet de découvrir groupes et acteurs, dans toute leur humanité. Le mur doit laisser place à la frontière. La porte ne peut rester fermée dans les deux sens. Les échanges sont le souffle de la vie. L’enjeu est tel qu’il réclame tout l’engagement du chercheur qui ne peut pas ne pas souligner et ne pas dénoncer tout ce qui voile, freine et altère l’humain.
Proyecto “Nueva Cultura”
Authors: Iriarte M.
Published: July 2012

Résumé Dans cet article, nous nous appuyons sur une expérience de terrain, dans le cadre d’un accompagnement d’une entreprise industrielle de 170 personnes qui a souhaité mettre en place une organisation horizontale. Cette nouvelle organisation devait intégrer les principes d’autogestion (notamment par la mise en place de mini-usines) et d’autonomie des personnes. Cependant, le fait de structurer la prise de décision pour mettre en place ce changement n’est pas suffisant et nécessite un véritable changement culturel. Nous proposons ainsi neuf principes méthodologiques pour structurer cette gestion du changement culturel.
Entumecimiento higrométrico del hormigón
Authors: Fernández Cánovas Manuel
Published: July 2012

Not avaible
Aplicaciones prácticas de la espectroscopía de absorción infrarrojo en el estudio de los crudos, del clínker y del cemento portland anhidro (Continuación)
Authors: Vázquez Tomás
Published: July 2012

Not avaible
Normalización del cemento. Tiempo de fraguado: algunos comentarios sobre el método de ensayo
Authors: Gaspar-Tébar Demetrio
Published: July 2012

Not avaible
Morteros y hormigones con cera: ¿una respuesta a la durabilidad?
Authors: Fernández Cánovas Manuel , Soto Margarita Cecilia
Published: July 2012

Not avaible
La serie de tamices de la DIN 1045 y la determinación del módulo de finura de Abrams
Authors: Grinszpan Pedro Enrique
Published: July 2012

Not available
Cementos que contienen 20 y 30 por ciento de cenizas volantes de Puentes de García Rodríguez y de Ponferrada
Authors: Santos Castro María Jesús
Published: July 2012

Not available
Consideraciones sobre el ensayo de ANSTETT y el comportamiento de los cementos frente a sulfatos
Authors: Calleja José , Aguanell Manuel
Published: July 2012

Not available
Observaciones a la "instrucción para el proyecto y la ejecución de las obras de hormigón pretensado" EP-77
Authors: Calleja José , Aguanell Manuel
Published: July 2012

Not available
Resistencia química del hormigón. V.-Acción del agua de mar: Influencia de la adición de escoria a un cemento portland resistente al yeso. Evolución de las resistencias mecánicas a flexotracción y del coeficiente de corrosión
Authors: Gaspar-Tébar Demetrio , Sagrera-Moreno José Luis
Published: July 2012

Not available
Nuevos puntos de vista sobre el ataque de sulfatos y cloruros alcalinos al hormigón
Authors: Veronelli D. J. E. , Calleja J.
Published: July 2012

Not available
Empleo racional de los cementos para los diferentes tipos de obras
Authors: Calleja José
Published: July 2012

Not available
Resistencia química del hormigón. VII.-Acción del agua de mar artificial que fluye a través de un lecho de mortero fabricado con un cemento portland resistente al yeso
Authors: Gaspar-Tébar Demetrio , Sagrera-Moreno José Luis , Díaz-Mora Rosario
Published: July 2012

Not available
Resistencia química del hormigón. VIII.-Acción del agua de mar: Influencia de la adición de escoria a un cemento portland. Evolución de las resistencias mecánicas a flexotracción y del coeficiente de corrosión
Authors: Sagrera-Moreno José Luis , Gaspar-Tébar Demetrio
Published: July 2012

Not available
Puesta al día de la colaboración científico-técnica española del I.E.T.C.C. con Iberoamérica en el campo del cemento y del hormigón
Authors: Calleja José
Published: July 2012

Not available
Resistencia química del hormigón. IX.- Influencia de la adición de escoria a un cemento portland de alta resistencia inicial. Estudio por DRX del sistema cemento 1/escoria-agua potable filtrada
Authors: Gaspar-Tébar Demetrio , Sagrera-Moreno José Luis
Published: July 2012

Not available
Aportación al estudio comparativo de resistencia a compresión entre cementos P-350 y PA-350
Authors: Morales Jiménez J. Enrique
Published: July 2012

Not available
Resistencia química del hormigón. X.- Influencia de la adición de escoria a un cemento portland resistente al yeso. Estudio por DRX del sistema cemento 2/escoria-agua potable filtrada
Authors: Sagrera-Moreno José Luis , Gaspar-Tébar Demetrio
Published: July 2012

Not available
Contribución al conocimiento del falso fraguado. Efectos de la langbeinita cálcica producida durante la clinkerización
Authors: Vázquez Moreno Tomás , Fernández Peña Olga
Published: July 2012

Not available
Técnicas electroquímicas cuali y cuantitativas para medir los efectos de las adiciones sobre la corrosión de las armaduras
Authors: Andrade C. , González J. A.
Published: July 2012

Not available
Resistencia química del hormigón. XI.- Contribución al estudio del sistema: cemento P-450-Y hidratado-agua desionizada
Authors: Gaspar-Tebar Demetrio , Sagrera-Moreno José Luis , Bermejo-Muñoz M. Francisca
Published: July 2012

Not available
El anacronismo de ciertas “instrucciones” oficiales y la necesidad de actualizarlas con urgencia
Authors: Calleja José , Sitges Francisco Lorenzo
Published: July 2012

Not available
Resistencia química del hormigón. XIII.- Contribución al estudio del sistema: cemento P-450-Y hidratado-disolución de sulfato del sodio
Authors: Bermejo-Muñoz M. Francisca , Sagrera-Moreno José Luis , Gaspar-Tebar Demetrio
Published: July 2012

Not available
En torno a las cenizas volantes en los cementos y en los hormigones, a la luz de un trabajo presentado en el 7º. Congreso Internacional de la Química de los Cementos
Authors: Calleja José
Published: July 2012

With reference to some comments recently made by the well known and informed author A. VIRELLA BLODA in a wide and detailed report on the Congress referred to, published in the Technical Review CEMENTO-HORMIGON, concerning the Round Table of Theme IV: POZZOLANAS AND FLY-ASHES and particularly to a paper presented under this item, the author of this work makes some personal considerations on pozzolanas in general and particularly on fly-ashes, dealing with general aspects of them, and more specifically with those related to reinforcement corrosion, which is the main object of the mentioned paper.
La deterioración de las piedras de la Catedral de Oviedo. 1ª Parte: Petrografía y porosidad características intrínsecas determinantes de la deterioración de sus rocas carbonatadas
Authors: Esbert Rosa M. , Marcos Rosa , Alonso Javier
Published: July 2012

The petrographic parameters and the physical properties controlling the alteration of the monumental stones of the Cathedral of Oviedo (Spain) are analized in this first paper. A special emphasis is placed on the characterization of the porosity, on account of the role this plays in the development of the forms and phenomena of superficial alteration.
Comentarios críticos de la Norma UNE 7245 sobre "determinación de los compuestos de azufre contenidos en los áridos"
Authors: Calleja José
Published: July 2012

This paper shows some deficiences of the Spanish Standard Method UNE 7245 and the corresponding deficiences of the Spanish Concrete Code EH-SO adopting it. According to the actual Method, erroneous low values may result in determining sulphides and in general sulphur compounds in cocrete aggregates.
Attention is drawn to the convenience of revising the limit of 1.2 per cent for the admissible maximum value of such compounds, particularly if they are exclusively formed by pyrites.
Escorias y cementos siderúrgicos
Authors: Calleja José
Published: July 2012

This paper describes the chemical and mineralogical characteristics which must show the blas-furnace slags to be used in cement manufacture or to be added to concrete. There are also shown technical and economical details concerning manufacture and use of blast-furnace slag cements. Methods to control the quality of slags and to determine their content in cements are mentioned and described as well.
Resistencia química del hormigón. XVI.- Acción del agua de mar: influencia de la adición de escoria a un cemento portland de alta resistencia inicial. Estudio por DRX
Authors: Gaspar-Tebar Demetrio , Sagrera-Moreno José Luis
Published: July 2012

In this work, a continuation of others, DRX studies the evolution of the structural characteristics of the enriched fraction (hydrated-attacked cement) extracted from one of the mortar prisms (1:3) o/ 1 x 1 x 6 cm of the different series manufactured with Portland cement of initial high resistance and with mixtures of cement/slag = 85/15, 65/35, 40/60 and 30/70, in weight, submerged in artificial sea water (ASTM D 1141) during 56, 90, 180 and 360 days —in this stage—, after the curing period (24 hours in an enclosure saturated with humidity and, following this, under potable water filtered during 21 days). Likewise DRX studies the structural composition of the new solid phases which have been formed in the means of conservation-attack (artificial sea water) where the series of mortar samples have been immersed.
In the DRX of the different enriched fractions, there have been identified, with variable intensity, the peaks of the ettringite, brucite and calcite, in all of them, of Friedel salt, except one, of gypsum and portlandite in part of them^ The intensify of the peaks of these composites depends on the mixture used in the manufacture of the mortar samples and on the time of conservation-attack.
In the DRX of the new solid phases there have been identified the peaks of the brucite, in two cases; when the mortar samples submerged in artificial sea water have been manufactured with Portland cement of initial high resistance and with the mixture which has the least content of slag (15 %). On the other hand, in all the cases studied there have been identified the peaks of the calcite and of the aragonite which present variable intensity, predominating those of one form on those of another according to the conditions of the system and, in a special manner, of the mixture used in the manufacture of the mortar samples.
Composición quimicomineralógica de las materias primas y ahorro de energía en la industria del cemento
Authors: Soria Santamaría Francisco
Published: July 2012

In the field of energy saving, mainly thermic, in the cement industry, not only should we consider the possibilities in the technological process or the finished product, but also the influence of the chemical-mineral composition of the raw materials.
The distinct parameters which fall into the reactivity of the crudes are analyzed, such as the size of the grain (fineness), chemical and mineral composition of the principal components. There follows an exposition of the importance of the minority components as smelting and mineralizers, finally emphasizing the interest and practical behaviour of some of them.
La deterioración de las piedras de la Catedral de Oviedo. 2° Parte: Formas y Fenómenos de Alteración
Authors: Esbert Rosa M. , Marcos Rosa
Published: July 2012

The different forms of superficial alteration that appear on the stones of the Oviedo Cathedral are described and localed, in this part of the paper. The more common phenomena of deterioration of the monument are also defined, stressing on the crusts.
Cenizas, cementos y hormigones con cenizas
Authors: Calleja José
Published: July 2012

This paper describes the chemical composition and the morfological nature of pulverized coal ashes, as well as their physical characteristics. Their influences —actions and effects— on the main properties and behaviour of cements and concretes, and the more adequate conditions for their efficient use un them are also described.
Precisiones sobre la corrosión del acero en contacto con hormigón
Authors: Andrade C.
Published: July 2012

In this paper, we emphasize that now it is possible to use some electrochemical non-destructive techniques for measuring the corrosion rate of the metals. Also, it is possible to use the gravimetric determinations if the appropriate instrumentation is not available. The simple visual observation is a good complementary technique but it must not be used alone because of its subjectivity.
Also, we stress some aspects, such as the influence of the alkalinity and the humidity, about the corrosion, that the bare and galvanized steel, can suffer in contact with construction materials.
We analyze mainly, the influence of the type of cement on the risk of corrosion of both kinds of metals.
Influencia de los componentes minoritarios de los carbones en la fabricación de cementos
Authors: Soria Santamaría Francisco
Published: July 2012

As a consequence of the reconversion of coal in the cement industry, it is considered important to analyze the incorporation and transcendence of certain components in the clinkerisation process.
Given in detail are the circuits of gases and volatile materials used in the baking process, emphasizing the interest of sulphur, alkalis, chlorides and fluorides.
Emphasized are the conditions and limits imposed in practice to certain components and the possibilities of application of the carbons in this sense.
Finally, a brief comment is made to the emission of dusts and contaminating gases, emphasizing the incidence in this field with the use of solid fuels in the furnaces to manufacture cement.
8º Congreso Internacional de la Química de los Cementos. Comité Científico Europa-Asia-África. 2ª Reunión del 14 de Septiembre de 1982, en París
Authors: Calleja José
Published: July 2012

In the present report the author, as the Spanish representative member in the meetings of the Europe-Asia-Afriqua Scientific Committee organizing the 8th International Congress on the Chemistry of Cements, which sponsored by Brazil will take place in Rio de Janeiro, July 1986, describes the course of the second committee meeting, for general information directed to the Spanish and Latin-American scientific and technical people interested in the theme.
On the matters treated in the first committee meeting the 14th September 1981 it was reported by the author in the technical reviews MATERIALES DE CONSTRUCCIÓN (lETCC) No. 83 (Jul-Aug-Sep 1981) pp. 5-14 and CEMENTO-HORMIGON No. 579 (Feb 1982) pp. 146-158.
Resistencia química del hormigón. XIII. Acción del agua de mar: influencia de la adición de escoria a un cemento portland resistente al yeso. Estudio por DRX
Authors: Gaspar-Tebar Demetrio , Sagrera-Moreno José Luis
Published: July 2012

In this work, which is a follow-up of others, the evolution of structural features of enriched fraction (attacked-hydrated cement) is studied by DRX, extracted from one of the mortar prisms (1:3) of 1 X 1 X 6 cm of the various series of test specimens made with a portland cement resistant to sulfate (cement 2) and with mixtures cement 2/scoria = 85/15, 65/35, 40/60 and 30/70, in weight, immersed in artificial sea water (ASTM D 1141-75) for 56, 90, 180 and 360 days-at this stage, following curing period (24 hours in a humidity saturated enclosure and up to 22 days under filtered drinking water). In addition, structural composition of the new solid phases formed in the preservation-attack media (sea water) was studied by DRX, where the mortar test pieces were immersed.
In the DRX of the various enriched fractions, the peaks of brucite, ettringite and calcite were identified with variable intensity in them all, and those of Friedel salt, gypsum and Portlandita in part. Intensity of these peaks depends on the mixture used when making the mortar test pieces and on the preservation-attack time.
In the DRX of the new solid phases, the peaks of calcite and aragonite were detected with variable intensity, and those of one form prevaidel over those of another, depending on system conditions and particularly on the cement 2/scoria mixture used to elaborate the mortar test pieces; the brucite peaks were in addition identified in the diagrams of the solid phases corresponding to the media where the mortar test pieces made with cement 2 and the mixture which has 15 % scoria were immersed.
La Normalización Nacional e Internacional de cementos
Authors: Soria Santamaría Francisco
Published: July 2012

A brief exposition of the situation and tendencies of the cement industry to contemplate its incidence in the development of norms of the conglomerates.
Comments are made on the historical development of the norms of cements in Spain and the present situation of the national norms at a world level.
Justifying the necessity of an international norm, the participation of ISO and other Bodies is required, emphasizing the requirement of work to be carried out by the Committee TC/51 of the CEN (European Committee of Standardization), in order to achieve a European standard on cements.
Reseña selectiva del Coloquio-Panel sobre: El futuro de los carbones españoles
Authors: Calleja José
Published: July 2012

Taking into account the general importance of the item showed in the title, and more particularly that concerning the Spanish Cement Industry considering the present and future energetic circumstances, this report presents the content of the mentioned Colloquim on "The Future of the Spanish Coals". Special mention is made to the use of national and imported coals according to their qualities, prices and supplies, taking into account the specific needs of the cement industry, as far as the use of solid fuels is concerned, with respect to the economic operation of the clinkering process and the good quality of the resulting cements.
Utilización de cenizas volantes y mineralizadores como materia prima en la fabricación de cemento
Authors: Blanco Varela Teresa , Vázquez Moreno Tomás , Palomo Sánchez Ángel
Published: July 2012

In this research the process of formation of a low energy clinker is studied, when fly-ashes (rich in sulphates and lime) and fluorspar are used as raw materials (fly-ashes replaces to the tradicional raw mix partially).
The availability of those fly-ashes is shown since clinker at 1.340 °C is obtained. The mineralogical composition, mineralizer capacity and temperature of formation of the new liquid phase is studied.
Ensayos de materiales en atmósferas simuladas. I. Criterios para el diseño de sistemas de simulación
Authors: Vale J. , Martín A.
Published: July 2012

This report begins with a series of three, comprising the construction of a universal system of ambiental simulation for accelerated tests of materials. If this first publication there are established, on the basis of the specialized bibliography, the criteria which should guide the designing of a system of this type, and likewise the experiencies of alteration.
After the revision of the types of tests at present existing, with an indication of the main advantages and inconveniences of each, there are described the phases which should lead to the implanting of a program of experiences of alteration, whose object may be the investigation of the mechanisms of the proccess or the evaluation of the measures of protection considered most adequate to improve the resistence of the different materials to polluted atmospheres. Finally, there are a series of considerations on the installations and techniques available for the simulation of atmospheres.
Consideraciones sobre el valor límite del contenido de SO4= en los áridos y materias primas para el hormigón
Authors: Gomá F.
Published: July 2012

The present paper points out the importance of three main subjects concerning the presence of sulphur compounds in concrete: i) the maximum sulphate content of concrete aggregates specified in the Spanish concrete standard; ii) the standardized analytical method to determine sulphur compounds in aggregates for concrete; and iii) the troubles caused by sulphides and sulphates in concrete.
The author suggests the possibility to revise the present limit for the content of sulphur in any state of valence in aggregates and other concrete materials, as well as the convenience to distinguish sulphur as sulphide from sulphur as sulphate in the total sulphur content of the aggregates, taking into account the different detrimental effects of both forms of sulphur in concrete.
Resistencia química del hormigón. XX. Acción del agua de mar: influencia de la adición de escoria a un cemento portland. Estudio por DRX
Authors: Gaspar-Tebar Demetrio , Sagrera-Moreno José Luis
Published: July 2012

In this work, which is a follow-up of others, the evolution of structural features of enriched fraction (attacked-hydrated cement) is studied by DRX, extracted from one of the mortar prims (1 : 3) of 1 X 1 X 6 cm of the various series of test specimens made with a Portland cement (cement 3) and mixtures cement 3/slag = 85/15, 65/35, 40/60 and 30/70, in weight, immersed in artificial sea water (ASTM D 1141-75) for 56, 90, 180 and 360 days -at this stage- following curing period (24 hours in humidity saturated enclosure and up to 22 days under filtered drinking water). In addition, structural composition was studied by DRX of the new solid phases formed in the preservation-attack media (artificial sea water) where the mortar test pieces were immersed.
In the DRX of the various enriched fractions, the peaks of brucite, ettringite and calcite were identified with variable intensity in them all, and those of Friedel salt, plaster and portlandite in part. Intensity of these peaks depends on the mixture used for making the mortar test pieces and on the preservation-attack time.
In the DRX of the new solid phases, the peaks of calcite and aragonite were detected with variable intensity, and those of one form prevailed over those of another, depending on system conditions and particularly, on the cement 3/slag mixture used to elaborate the mortar test pieces; the brucite peaks were in addition identified in the diagrams of the solid phases corresponding to media where the mortar test pieces made with cement 3 and the mixture which has 15% slag were immersed.
Adiciones y cementos con adiciones
Authors: Calleja José
Published: July 2012

The present paper deals with aspects concerning the conditions to be fulfilled by raw materials and manufacturing process of cements containing components other than clinker and setting regulator.
It deals also with proper conditions for the utilization of these cements, as well as with the knowledge of the interrelation between manufacture and use of them, in order to aid the manufacturers and the users in the better profit o such energy saving blended cements in optimal technical and economical conditions.
Características físicas y alterabilidad de la piedra de Villamayor (Salamanca)
Authors: Ordaz Jorge
Published: July 2012

Physical properties of Villamayor sandstone (Salamanca), and especially porosity, water absorption and capillary flow through rock are studied in relation to its lithological characteristics. Laboratory weatherability tests (wetting-drying, freezing-thawing, and salt crystallisation) shows the susceptibility to destructive effects of frost and humidity fluctuations, and provides estimated data about the potential durability of this building stone.