bluuebunny/crossref_metadata_2025 huggingface dataset:
The Thermal Recovery Methods and Technical Limits of Bohai Offshore Heavy Oil Reservoirs: A Case Study
Authors: Dong Xiaohu , Liu Huiqing , Hou Jirui , Zhang Tianlin , Zhan Jie , Chen Zhangxin , Hong Cheng
Published: October 2015

Heavy oil accounts for a large proportion in offshore petroleum reserves. For Bohai offshore oilfield in China, about 85% of the OOIP is the heavy oil. Heavy oil has become an important form to guarantee the offshore oil production. Considering the limited space in offshore oil platform, cold production method is the commonly-used development method. But for some heavy oils with higher viscosity (>350cp), cold production method is less effective, and thermal recovery process will be a better choice. In this paper, we focuses on three different heavy oil reservoirs from Bohai offshore oilfield, including the blocks of NB35-2, LD-1 and LD-2. These three blocks essentially represents the main heavy oil reservoir types of Bohai oilfield (edge-water, bottom-water and thick oillayer). Then through the analogical analysis between onshore reservoirs and offshore reservoirs, the development methods for the three blocks are determined firstly. In this process, we make a survey on the development status of onshore heavy oil reservoirs in China. Then, based on the geological properties of the three blocks, a set of numerical simulation runs are performed to analyze the influence of many sensitive factors (e.g., reservoir depth, thickness, permeability, net-to-gross and water-zone). After that, through the computation of net present value (NPV), we reevaluate the economic limit indexes of thermal recovery process in Bohai offshore heavy oil reservoirs and determine the technical limits.

From the analogical results, it is concluded that different heavy oil reservoir will have different thermal recovery method. For the three heavy oil reservoirs, cyclic steam stimulation (CSS) process is a potential EOR method for block LD-1, and steam flooding is a better choice for NB35-2, and LD-2 could adopt the methods of steam flooding process and SAGD process. From the numerical simulation results and NPV results, we found it is not economical to perform a CSS process in LD-1. For the other two blocks, NB35-2 and LD-2, the economical cumulative oil-steam ratios under the corresponding thermal recovery methods are calculated. And the technical limit of thermal recovery process in Bohai offshore heavy oil reservoirs are derived. It shows that a steam flooding process is suitable to the edge-water heavy oil reservoirs in Bohai oilfield whose heterogeneity is relatively weak, formation is relatively thin (10m<thickness <25 m), and water zone energy is low (water/oil ratio<5). And a steam flooding process is suitable to the heavy oil reservoirs in Bohai oilfield whose thickness is higher than 30m, net-to-gross is greater than 0.55, and reservoir depth is less than 1400 m. This work is useful to extend the thermal recovery process in Bohai offshore heavy oil reservoirs. It will play an important role for the effective development of offshore heavy oil reservoirs.
Re-Interpretation of an Ultra-Deep Seismic Section in the Pará-Maranhão Basin - Implications for the Petroleum Potential of the Ultra-Deep Waters
Authors: Zalán P. V.
Published: October 2015

A very long (736 km) and ultra-deep (PSDM 40 km) seismic section, oriented in the dip direction (NE-SW), was re-interpreted from a previously published interpretation. The main differences regarding these two versions concern the nature of the continental-oceanic boundary, the dimensions of the underlying rift sections situated in the continental slope area and the petroleum potential of the Drift Supersequence in the ultra-deep waters.

The line was re-interpreted using the modern concepts of rupture and break-up of mega-continents, presently used by the petroleum industry worldwide. The petroleum-rich passive continental margins are nowadays classified into two end-members: magma-poor or sedimentary passive margins and volcanic passive margins. The analysis performed indicated that the Pará-Maranhão Basin can be classified as a typical magma-poor passive margin developed during the oblique dextral separation between South America and Africa.

The original thickness of the continental crust below the shallow waters of the basin is in the order of 32 km. The Moho reflection is easily observable and shallows up gradually to depths around 12-13 km where it forms a small plateau before meeting the top of the crystalline basement. The continental crust tapers significantly and forms a narrow band of hyper-extended crust (circa 30 km wide) before being broken by a clear stretch of exhumed mantle (around 30 km wide). Oceanic crust follows in a typical tabular shape with thicknesses between 5-6 km. At the northeastern end of the line, the Moho dips deeply under the Ceará Rise, suggesting a typical continental crustal profile for this feature. In being so, the Ceará Rise could be interpreted as a significantly large micro-continent.

The results of this interpretation indicate a high potential for the Drift Supersequence in ultra-deep waters where the thickness of sediments reaches 8 km. Strong and large bright spots surround a structural high situated upon the exhumed mantle, buried underneath edifices of volcanic intrusions. Their seismic facies suggest turbidites filled with fluids deposited around a syn-tectonic high. Older generation seismic lines did not have resolution to highlight these leads. The shallow gravitational cells in deep waters also overlie high potential deeper Drift Supersequence sections. Besides unravelling the crustal structure underneath the Pará-Maranhão continental margin, this interpretation also expanded horizontally and vertically the prospectable area of the basin. It proved that petroleum potential may exist beyond the termination of the continental crust, upon the exhumed mantle.
Technology Evaluation System for Detection of CO2 and CH4 in Deepwater Fields
Authors: Esteves V. P. P. , Wanke B. S. L. , D'Avila C. J. R. , de Mello C. S. B. , Grava W. M. , McLean S.
Published: October 2015

In the deep water pre salt Santos Basin Petrobras is interested in potential monitoring technologies for detection of carbon dioxide (CO2) in seawater at depths between 1200 and 2600 meters. At these depths, CO2 is not a gas but a buoyant liquid with densities similar to sea water, which makes detection challenging. Also potentially present with CO2 is methane (CH4), which at these depths is close to liquid-hydrate combination, which may possibly cause interference with some measurement techniques used for CO2.

The Federal University of Rio de Janeiro (UFRJ), Ocean Networks Canada (ONC) and Petrobras are developing a test system where carbon dioxide (CO2) and methane (CH4) can be released in controlled amounts to a variety of test instruments at a depth of 2660 meters located over a secure Internet connection with collecting sensor and live video monitoring.

So far, the project has selected several sensors developed by universities, research centers and companies around the world, using different technologies including fiber optic, acoustic and pH. Enabling this in situ real time experimentation is the ONC NEPTUNE cabled observatory. With over 800 kilometers of electro-optic cable to depths of 2660 meters the observatory provides power and Internet connectivity to hundreds of underwater instrumentation making it an ideal laboratory to evaluate technologies in situ. We will describe the design of the experiment at the Cascadia Basin site.
A Low Field NMR Investigation on Rock Wettability by Formulations Used for Enhanced Oil Recovery
Authors: Ungarato R. F S. , Sabadini E. , Loh W.
Published: October 2015

Mixtures containing surfactants and polymers to be used in enhanced oil recovery operations should display special features: most notably low (or ultra-low) oil/water interfacial tensions and moderate viscosity. There is a variety of methods employed to assess formulations performance for enhanced oil recovery. Some of these involved wettability measurements, such as the Amott test, but these are typically time consuming.

This communication reports on the use of low-field nuclear magnetic resonance (NMR) to probe rock wettability in the presence of different formulations. Based on the relaxations time, this technique allows a direct assessment of molecular mobility, which in turn is determined if the liquid is bounded to surfaces or free. Based on this, it is possible to monitor the exchange of oil from the porous of rock by water solution. Therefore, the efficiency of formulations can be determined.

Two rock samples, sandstone and carbonate, were employed to reproduce some reservoir conditions. These were first impregnated with oil samples and then exposed to different aqueous formulations and the fractions of oil and water were directly monitored based on the measurement of the spin-spin relaxation time of the hydrogen atoms.

Typical formulations included mixtures of non-ionic and zwitterionic surfactants and high molar mass polymers. These surfactants display little propensity to ion strength effects and cloud points associated to lower interfacial tension values that could be varied with composition. Effects such as nature of the surfactant chain (double vs. single chain, chain length) and mixture composition with respect to their cloud points were found relevant to affect oil displacement capacity.

These results confirm the validity and advantages of this technique, as well as reveal important information about surfactant mixtures with potential for use in enhanced oil recovery.
Advancements in Commercial Sensor Packages for Underwater Gliders
Authors: Creed E. , Patterson R.
Published: October 2015

Conventional monitoring of the oceans using ships is a labor intensive and costly exercise that yields low resolution temporal and spatial record of the ocean environment. However, over the last decade underwater gliders, propeller-less AUVs that glide through the water by changing their buoyancy, have become mainstream collectors of oceanographic data and are replacing ships as the main means of data collection in some locales. Early gliders were designed to carry a very limited science sensor payload, a CT (conductivity and temperature) or CTD (conductivity, temperature and depth) system. However, as glider popularity has grown over the last 8-10 years so has the demand to increase the diversity and number of sensors that can be carried by these vehicles. The initial selection of small size, relatively low power, greater than 1000 m rated sensors was limited. However, sensor vendors have begun working on next generation sensor packages for some of the systems whose original power, size and weight footprint was too large for an underwater glider. In this paper we will discuss three sensor packages that have been redesigned and can now be integrated into gliders.
Pensamiento arquitectónico y criterios gráficos en la modelización de algunos proyectos tardo-góticos de Hernán Ruiz "el Viejo"
Authors: Ampliato Briones Antonio Luis , Gimena Córdoba Pilar
Published: October 2015

This paper primarily reflects on the need to create graphical codes for producing images intended to communicate architecture. Each step of the drawing needs to be a deliberate process in which the proposed code highlights the relationship between architectural theory and graphic action. Our aim is not to draw the result of the architectural process but the design structure of the actual process; to draw as we design; to draw as we build. This analysis of the work of the Late Gothic architect Hernan Ruiz the Elder, from Cordoba, addresses two aspects: the historical and architectural investigation, and the graphical project for communication purposes. 
La ingeniería al servicio de la historia: imágenes invisibles del Paleolítico
Authors: Gutiérrez Alonso Aroa , Farjas Abadía Mercedes , Domínguez Gómez José Antonio
Published: October 2015

This article aims to describe the development of a new non-invasive methodology, through techniques and tools of digital image processing to optimize materials and time in obtaining graphical representative and accurate information from petroglyphs and rock paintings belonging to Paleolithic. 
El Estudio Paramental en el Modelo de Información del Edificio Histórico o “Proyecto HBIM”
Authors: Nieto Julián Juan Enrique , Moyano Campos Juan José
Published: October 2015

The Building Information Modeling (BIM) has now become a collaborative system that greatly benefits the industries involved in the AEC sector. The essence of BIM is to be a container core with graphic and alphanumeric information, where each discipline participatory dump their knowledge to suit the peculiarities of the building in coordination with the other agents involved. If this same scenario is moved to Heritage, we see that the needs are the same; archaeologist, architect, historian, restorer or engineer are at the same crossroads when it comes to passing on their assumptions and subject to debate before approval. The article will present an effective methodology to implement the stratigraphic study of surfaces. The intention is to dump the information gathered in Phase auscultation in a single graphical model, operating from different disciplines and allows inter operationalize avoiding unnecessary data duplication and contradictory. An intervention project supported by an information model of the Historic Building, which we can call HBIM Project (Historic Building Information Modelling Project) is established.
El museo virtual de los misteriosos Stećci
Authors: López-Menchero Bendicho Víctor Manuel , Rizvic Selma
Published: October 2015

The online virtual museums seem to consolidate as excellent platforms for dissemination of cultural heritage, especially in countries with few resources and hard to take conservation and dissemination of their heritage. The Stecci virtual museum, developed by the University of Sarajevo (Bosnia-Herzegovina) is a clear example of how new technologies can contribute to enhancing cultural heritage.
Effects of dietary soybean and sunflower oils with and without L-carnitine supplementation on growth performance and blood biochemical parameters of broiler chicks
Authors: Jalali S. M. A. , Rabiei R. , Kheiri F.
Published: October 2015

Abstract. An experiment was designed to investigate the effects of soybean, sunflower oil and dietary L-carnitine supplementation on growth performance, some blood biochemical parameters and antibody titer against Newcastle disease of broiler chicks. A 5-week feeding trial, 240 1-day old male broiler chicks (Ross 308) were randomly allocated to six dietary treatments as a 3 × 2 factorial experimental design where three sources of dietary oil contained soybean, sunflower and soybean plus sunflower oil with and without 120 mg kg−1 of L-carnitine supplementation in the diet. Results showed that soybean oil with L-carnitine significantly improved body weight gain and feed conversion ratio of broiler chicks in the grower and total period of rearing (p < 0.05). L-carnitine supplementation significantly increased total protein, globulin, cholesterol, HDL and LDL (high- and low-density lipoprotein) of blood serum in broiler chicks (p < 0.05). L-carnitine supplementation increased antibody titer against Newcastle disease of chicks and the highest levels were observed in those with the supplement of L-carnitine in the soybean oil dietary treatment. Results of this experiment showed that the growth performance and blood biochemical responses of broiler chicks to dietary supplementation with L-carnitine in dietary oil source and soybean oil, in comparison to sunflower oil, is the better plant oil for growth and immunological performance of broiler chicks.
Can The United Nations Security Council Be Democratized?
Authors: Ade-Ibijola Aderemi Opeyemi
Published: October 2015

The quest for the democratization of the United Nations Security Council (UNSC) is one of the most critical issues that has confronted the United Nations (UN) system for the better part of the organization’s existence. To this end, this paper examines the call for the democratization of the UNSC and the challenges thereof. It argues that the attempts to democratize the UNSC has been unsuccessful due to fact that the UNSC was not designed to be a democratic organ from its inception. The paper submits that a democratically constituted UNSC will lead to chaos and disorder in the international system.
New Horizons for GAG Therapy in the Management of Urothelial Damage
Authors: Lazzeri Massimo
Published: October 2015

Urothelial defects may manifest as various types of signs of symptoms such as frequency and urgency, haematuria and pain. Both prevention and treatment of urothelial damage is fundamental. Many currently adopted treatments lack robust clinical data and are associated with variability in management strategies. Glycosoaminoglycan (GAG) therapy is one of the most promising therapies in treatment of chemotherapy and radiotherapy-induced urothelium defects, and has been investigated in both animal models and clinical studies.
Physics Essay: Six Baseless and Irrational Problems in Modern Cosmology
Authors: Li Zifeng
Published: October 2015

Analyzes the Big Bang theory, recession of galaxies, Hubble's law, multi-dimensional space, curved space and black hole in modern cosmology and points out that these six theories are all baseless and irrational, contrary to classical science. Promotes the use of plain view of the universe - the materialist view of space–time-mass-energy to study the universe. The observations and understanding of the universe are very limited now. Cosmology should be realistic, not based on irrational models.
Chemical Composition of Common Seaweeds from the Kenya Coast
Authors: Mwalugha Heltan M. , Wakibia Joseph G. , Kenji Glaston M. , Mwasaru Mwanjala A.
Published: October 2015

The gross nutritional profile of 34 seaweed species from three sites (Mkomani, Kibuyuni and Mtwapa) in coastal Kenya were studied. The crude fat, crude protein, crude fibre and crude ash were determined by the standard AOAC methods while the nitrogen-free extract (NFE) was calculated by weight difference of the chemical components. The chemical constituents of the seaweeds varied significantly among the algal divisions, species, months and sites (p<0.05). The major chemical components was the NFE with a mean value of 42.09 ± 0.83% dry weight (DW) followed by crude ash (31.94 ± 0.78% DW), crude fibre (14.08 ± 0.26% DW), crude protein (10.09 ± 0.26% DW), whereas the least component was crude fat with a mean value of 1.81 ± 0.04% DW (p<0.05). The crude protein levels were positively correlated with nitrogen content and in crude fibre and negatively with NFE, crude fat and crude ash (p<0.05). The findings on the gross nutritional profile of the seaweeds in this study could be used as a basis for more advanced research on nutritional information guideline and as potential resources for seaweed-based products for improved human and animal nutrition.
Veranderende mensbeelden van gedetineerden
Authors: Kelk C.
Published: October 2015

Changing portrayals of detainees. A short historic overview

Throughout history the way detainees were portrayed by society has varied. At first, until the Second World War, detainees were mainly seen as blameworthy objects. After the war they became a fellow human being with dignity in need of resocialization or psychological treatment. In the Seventies detainees became citizens with a legal status according to the rule of law. When in the Eighties criminal law became more punitive, prisoners developed into enemies of society. Since then the detainee is moreover seen as dangerous and as a risk. Consequently the desirability of resocialization is questioned. This has resulted in a more individual approach towards prisoners, who need to prove that they are motivated for resocialization programs. In the end this leaves the most vulnerable detainees to their fate and expresses a view of man which could be characterized as the lost human.
De terugkeer van de ‘kinderlijke delinquent’?
Authors: Weijers I.
Published: October 2015

The return of the ‘childlike nature’ of young offenders? Changing images of the child in the history of Dutch juvenile justice

This article gives a historical sketch of a century of juvenile justice in the Netherlands. It focuses on the development of the concept of childhood from the beginning of the twentieth century to the present. Starting from the notion of degeneration and the idea of the neglected child, in the thirties a psychologization process emerged. Crucial was the notion of the childlike nature of the behavior of minor offenders, which was clearly inspired by new insights coming from pedagogy, developmental psychology and child psychiatry. The author argues that recently, after some decades showing a trend towards more toughness on crime, there are indications of a reemergence of the notion of the childlike nature of young delinquents, again inspired by knowledge and insights from the behavioral sciences but also from neurology and brain research.
The effects of customization on motivation in an extended study with a massively multiplayer online roleplaying game
Authors: Turkay Selen , Adinolf Sonam
Published: October 2015

Customization is a ubiquitous feature of games and can be perceived as a series of choices that may influence players’ experiences. Opportunities for customization may give users decision-making authority over the technology, enabling them to shape and create their own experiences, as well as provide ways to be a part of a group based on their needs and desires. This study aims to shed more light on the effects customization has on players’ motivation, and investigates how customization as a way of user control affects player motivation within an MMO. A mixed method study was designed with two conditions: customization (n = 33) and no customization (n = 33). Adult participants played Lord of the Rings Online (LotRO), a Massively Multiplayer Online game, for about ten hours over four sessions. Data was collected through surveys, interviews and observations. Results showed that players’ desire to replay the game increased over time, and customization affected players’ motivation positively. Findings are discussed through the lens of Self-Determination Theory (Deci & Ryan, 1985).
A psychologically “embedded” approach to designing games for prosocial causes
Authors: Kaufman Geoff , Flanagan Mary
Published: October 2015

Prosocial games often utilize a direct, explicit approach to engage players with serious real-life scenarios and present information about key societal issues. This approach, however, may limit a game’s persuasive impact and ability to produce beneficial outcomes, particularly when the apparent aims of the game trigger players’ psychological defenses or reduce players’ potential engagement with – and enjoyment of – the game experience. In contrast, the “Embedded Design” approach that we introduce here offers effective, evidence-based strategies for more stealthily or covertly delivering persuasive content in a game in a fashion that circumvents players’ psychological defenses and triggers a more receptive mindset. This paper provides an in-depth exploration of two key Embedded Design strategies: (1) intermixing: combining “on-topic” and “off-topic” game content in order to make the focal message or theme less obvious and more accessible and (2) obfuscating: using game genres or framing devices that direct players’ attention or expectations away from the game’s true aims. To illustrate the implementation and effectiveness of these strategies, we detail the design of two games that utilize a number of these techniques to reduce stereotypes and biases and present the methods and results of a set of empirical studies testing the prosocial impact of these games. In addition, we introduce a number of other Embedded Design strategies that have emerged in our work and discuss the most viable contexts for the use of this design approach.
El Paso's Advanced Water Purification Facility: A New Direction in Potable Reuse
Authors: Maseeh George P. , Russell Caroline G. , Villalobos Sanaan Lair , Balliew John E. , Trejo Gilbert
Published: October 2015

El Paso Water Utilities is developing a new advanced water purification facility, a frontrunner in the direct potable reuse arena that will help diversify its water resource portfolio.
Rechtsvergleichende Einordnung von Preisschirmeffekten (Umbrella Pricing) in das Kartellschadensersatzrecht
Authors: Eckel Philipp
Published: October 2015

Der Beitrag gibt einen Überblick über die Frage der schadensersatzrechtlichen Ersetzbarkeit von Preisschirmschäden nach der Entscheidung des EuGH in der Rs. „Kone“ und würdigt kritisch die Reaktionen in der deutsch- und englischsprachigen Literatur auf das Urteil, indem u.a. das Erfordernis eines zweigliedrigen Zurechnungstatbestandes mit einer doppelten Vermutungsregel betont und die Behandlung der Kronzeugenregelungen durch den Gerichtshof abgelehnt werden. Rechtsvergleichend wird aufgezeigt, dass einige Erfahrungswerte aus Rechtsprechung und Literatur zum US-amerikanischen Antitrust Law auch für die unionsrechtliche Beurteilung von umbrella pricing fruchtbar gemacht werden können und dass sich die Anforderungen des EuGH unter Berücksichtigung der bisherigen nationalen Praxis zu Preisschirmeffekten ohne weiteres in das nationale Kartelldeliktsrecht des Vereinigten Königreichs und Österreichs implementieren lassen. Die Abhandlung schließt mit einer ausführlichen Einordnung des EuGH-Urteils in das deutsche Schadensrecht unter Berücksichtigung der bisherigen BGH-Rechtsprechung und argumentiert für eine Berücksichtigung von Preisschirmeffekten über den identischen relevanten Markt hinaus. Umbrella Pricing after the ECJ’s decision in „Kone“: A comparative analysis and classification into the German tort law This paper provides an overview of the requirements of compensation of umbrella damages according to the ECJ’s decision in „Kone“ and comments critically on the reactions on this decision in German and Englishspeaking literature stressing the imperative of a two-part causation-requirement and criticising the ECJ’s argument about the leniency programme. A comparative analysis shows that assessment under European Law may benefit from the jurisprudence and literature in US Antitrust Law and that the requirements stated in „Kone“ can be implemented into the national tort laws of the United Kingdom and Austria without further problems. The paper ends with a detailed classification of the principles established in „Kone“ into the German tort law considering the previous national jurisprudence and argues in favour of the compensation of umbrella damages from neighbouring markets.
Scalable Production of Edge‐Functionalized Graphene Nanoplatelets via Mechanochemical Ball‐Milling
Authors: Jeon In‐Yup , Bae Seo‐Yoon , Seo Jeong‐Min , Baek Jong‐Beom
Published: October 2015

Although there are a variety of methods for producing graphene, commercialization remains challenging because each method has its own pros and cons. For the wide use of graphene as a next generation material in diverse applications, the process by which graphene is manufactured must be robust enough to overcome barriers to commercialization, as has been experienced in commercializing carbon nanotube products. Here, a recent discovery of a new manufacturing process for efficient delamination of graphite into graphene nanoplatelets (GnPs) via mechanochemical ball‐milling is summarized. In this process, transferring sufficient kinetic energy to graphitic frameworks will crack graphitic C–C bonds, generate active carbon species (mostly carbon free radicals), introduce edge‐functional groups, and delaminate graphitic layers into edge‐functionalized GnPs (EFGnPs). While this process is a method for mass production, it does not involve hazardous chemicals (e.g., corrosive acids and toxic reducing agents) such as those used for producing graphene oxide (GO) and reduced graphene oxide (rGO). Owing to its edge‐selective functionalization, the EFGnPs have minimal basal area defects with selectivity of a variety of edge groups by forming edge C–X bonds (X = nonmetals or metalloids) that are tunable.
Cooperative Cluster Metalation and Ligand Migration in Zirconium Metal–Organic Frameworks
Authors: Yuan Shuai , Chen Ying‐Pin , Qin Junsheng , Lu Weigang , Wang Xuan , Zhang Qiang , Bosch Mathieu , Liu Tian‐Fu , Lian Xizhen , Zhou Hong‐Cai
Published: October 2015

Cooperative cluster metalation and ligand migration were performed on a Zr‐MOF, leading to the isolation of unique bimetallic MOFs based on decanuclear Zr6M4 (M=Ni, Co) clusters. The M2+ reacts with the μ3‐OH and terminal H2O ligands on an 8‐connected [Zr6O4(OH)8(H2O)4] cluster to form a bimetallic [Zr6M4O8(OH)8(H2O)8] cluster. Along with the metalation of Zr6 cluster, ligand migration is observed in which a Zr–carboxylate bond dissociates to form a M–carboxylate bond. Single‐crystal to single‐crystal transformation is realized so that snapshots for cooperative cluster metalation and ligand migration processes are captured by successive single‐crystal X‐ray structures. In3+ was metalated into the same Zr‐MOF which showed excellent catalytic activity in the acetaldehyde cyclotrimerization reaction. This work not only provides a powerful tool to functionalize Zr‐MOFs with other metals, but also structurally elucidates the formation mechanism of the resulting heterometallic MOFs.
A Triphasic Sorting System: Coordination Cages in Ionic Liquids
Authors: Grommet Angela B. , Bolliger Jeanne L. , Browne Colm , Nitschke Jonathan R.
Published: October 2015

Host–guest chemistry is usually carried out in either water or organic solvents. To investigate the utility of alternative solvents, three different coordination cages were dissolved in neat ionic liquids. By using 19F NMR spectroscopy to monitor the presence of free and bound guest molecules, all three cages were demonstrated to be stable and capable of encapsulating guests in ionic solution. Different cages were found to preferentially dissolve in different phases, allowing for the design of a triphasic sorting system. Within this system, three coordination cages, namely Fe4L6 2, Fe8L12 3, and Fe4L4 4, each segregated into a distinct layer. Upon the addition of a mixture of three different guests, each cage (in each separate layer) selectively bound its preferred guest.
Fabrication of Two‐Dimensional Lateral Heterostructures of WS2/WO3⋅H2O Through Selective Oxidation of Monolayer WS2
Authors: Zhou Pengshang , Xu Qun , Li Hongxiang , Wang Yun , Yan Bo , Zhou Yunchun , Chen Jiafu , Zhang Jianan , Wang Kaixi
Published: October 2015

Two‐dimensional (2D) lateral heterostructures have emerged as a hot topic in the fast evolving field of advanced functional materials , but their fabrication is challenging. The layer‐structured WS2 was theoretically demonstrated to be inert to oxidation except for the monolayer, which can be selectively oxidized owing to the simultaneous interaction of oxygen with both sides. Combined with the theoretical calculations, a new method was developed for the successful construction of 2D lateral heterostructures of WS2/WO3⋅H2O in an ambient environment, based on a simple liquid‐phase solution exfoliation. These lateral heterostructures of WS2/WO3⋅H2O have interesting properties, as indicated by enhanced photocatalytic activity toward the degradation of methyl orange (MO).
Surface‐Specific Functionalization of Nanoscale Metal–Organic Frameworks
Authors: Wang Shunzhi , Morris William , Liu Yangyang , McGuirk C. Michael , Zhou Yu , Hupp Joseph T. , Farha Omar K. , Mirkin Chad A.
Published: October 2015

A method for modifying the external surfaces of a series of nanoscale metal–organic frameworks (MOFs) with 1,2‐dioleoyl‐sn‐glycero‐3‐phosphate (DOPA) is presented. A series of zirconium‐based nanoMOFs of the same topology (UiO‐66, UiO‐67, and BUT‐30) were synthesized, isolated as aggregates, and then conjugated with DOPA to create stably dispersed colloids. BET surface area analysis revealed that these structures maintain their porosity after surface functionalization, providing evidence that DOPA functionalization only occurs on the external surface. Additionally, dye‐labeled ligand loading studies revealed that the density of DOPA on the surface of the nanoscale MOF correlates to the density of metal nodes on the surface of each MOF. Importantly, the surface modification strategy described will allow for the general and divergent synthesis and study of a wide variety of nanoscale MOFs as stable colloidal materials.
Achieving complete nitrogen removal by coupling nitritation‐anammox and methane‐dependent denitrification: A model‐based study
Authors: Chen Xueming , Guo Jianhua , Xie Guo‐Jun , Yuan Zhiguo , Ni Bing‐Jie
Published: October 2015

The discovery of denitrifying anaerobic methane oxidation (DAMO) processes enables the complete nitrogen removal from wastewater by utilizing the methane produced on site from anaerobic digesters. This model‐based study investigated the mechanisms and operational window for efficient nitrogen removal by coupling nitritation‐anaerobic ammonium oxidation (Anammox) and methane‐dependent denitrification in membrane biofilm reactors (MBfRs). A mathematical model was applied to describe the microbial interactions among Anammox bacteria, DAMO archaea, and DAMO bacteria. The model sufficiently described the batch experimental data from an MBfR containing an Anammox‐DAMO biofilm with different feeding nitrogen compositions, which confirmed the validity of the model. The effects of process parameters on the system performance and microbial community structure could therefore be reliably evaluated. The impacts of nitritation produced NO2−/NH4+ ratio, methane supply, biofilm thickness and total nitrogen (TN) surface loading were comprehensively investigated with the model. Results showed that the optimum NO2−/NH4+ ratio produced from nitritation for the Anammox‐DAMO biofilm system was around 1.0 in order to achieve the maximum TN removal (over 99.0%), independent on TN surface loading. The corresponding optimal methane supply increased while the associated methane utilization efficiency decreased with the increase of TN surface loading. The cooperation between DAMO organisms and Anammox bacteria played the key role in the TN removal. Based on these results, the proof‐of‐concept feasibility of a single‐stage MBfR coupling nitritation‐Anammox‐DAMO for complete nitrogen removal was also tested through integrating the model with ammonia‐oxidizing bacteria (AOB) and nitrite‐oxidizing bacteria (NOB) processes whilst controlling the dissolved oxygen (DO) concentration in the simulated system. The maximum TN removal was found to be achieved at the bulk DO concentration of around 0.17 g m−3 under the simulation conditions, with the AOB, Anammox bacteria and DAMO organisms coexisting in the biofilm. Biotechnol. Bioeng. 2016;113: 1035–1045. © 2015 Wiley Periodicals, Inc.
Microscale profiling of photosynthesis‐related variables in a highly productive biofilm photobioreactor
Authors: Li Tong , Piltz Bastian , Podola Björn , Dron Anthony , de Beer Dirk , Melkonian Michael
Published: October 2015

In the present study depth profiles of light, oxygen, pH and photosynthetic performance in an artificial biofilm of the green alga Halochlorella rubescens in a porous substrate photobioreactor (PSBR) were recorded with microsensors. Biofilms were exposed to different light intensities (50–1,000 μmol photons m−2 s−1) and CO2 levels (0.04–5% v/v in air). The distribution of photosynthetically active radiation showed almost identical trends for different surface irradiances, namely: a relatively fast drop to a depth of about 250 µm, (to 5% of the incident), followed by a slower decrease. Light penetrated into the biofilm deeper than the Lambert‐Beer Law predicted, which may be attributed to forward scattering of light, thus improving the overall light availability. Oxygen concentration profiles showed maxima at a depth between 50 and 150 μm, depending on the incident light intensity. A very fast gas exchange was observed at the biofilm surface. The highest oxygen concentration of 3.2 mM was measured with 1,000 μmol photons m−2 s−1 and 5% supplementary CO2. Photosynthetic productivity increased with light intensity and/or CO2 concentration and was always highest at the biofilm surface; the stimulating effect of elevated CO2 concentration in the gas phase on photosynthesis was enhanced by higher light intensities. The dissolved inorganic carbon concentration profiles suggest that the availability of the dissolved free CO2 has the strongest impact on photosynthetic productivity. The results suggest that dark respiration could explain previously observed decrease in growth rate over cultivation time in this type of PSBR. Our results represent a basis for understanding the complex dynamics of environmental variables and metabolic processes in artificial phototrophic biofilms exposed to a gas phase and can be used to improve the design and operational parameters of PSBRs. Biotechnol. Bioeng. 2016;113: 1046–1055. © 2015 Wiley Periodicals, Inc.
Scaffold and scaffold‐free self‐assembled systems in regenerative medicine
Authors: Thomas Dilip , Gaspar Diana , Sorushanova Anna , Milcovich Gesmi , Spanoudes Kyriakos , Mullen Anne Maria , O'Brien Timothy , Pandit Abhay , Zeugolis Dimitrios I.
Published: October 2015

Self‐assembly in tissue engineering refers to the spontaneous chemical or biological association of components to form a distinct functional construct, reminiscent of native tissue. Such self‐assembled systems have been widely used to develop platforms for the delivery of therapeutic and/or bioactive molecules and various cell populations. Tissue morphology and functional characteristics have been recapitulated in several self‐assembled constructs, designed to incorporate stimuli responsiveness and controlled architecture through spatial confinement or field manipulation. In parallel, owing to substantial functional properties, scaffold‐free cell‐assembled devices have aided in the development of functional neotissues for various clinical targets. Herein, we discuss recent advancements and future aspirations in scaffold and scaffold‐free self‐assembled devices for regenerative medicine purposes. Biotechnol. Bioeng. 2016;113: 1155–1163. © 2015 Wiley Periodicals, Inc.
Analogues of Cis‐ and Transplatin with a Rich Solution Chemistry: cis‐[PtCl2(NH3)(1‐MeC‐N3)] and trans‐[PtI2(NH3)(1‐MeC‐N3)]
Authors: Siebel Sabine , Dammann Claudia , Sanz Miguel Pablo J. , Drewello Thomas , Kampf Gunnar , Teubner Natascha , Bednarski Patrick J. , Freisinger Eva , Lippert Bernhard
Published: October 2015

Mono(nucleobase) complexes of the general composition cis‐[PtCl2(NH3)L] with L=1‐methylcytosine, 1‐MeC (1 a) and L=1‐ethyl‐5‐methylcytosine, as well as trans‐[PtX2(NH3)(1‐MeC)] with X=I (5 a) and X=Br (5 b) have been isolated and were characterized by X‐ray crystallography. The Pt coordination occurs through the N3 atom of the cytosine in all cases. The diaqua complexes of compounds 1 a and 5 a, cis‐[Pt(H2O)2(NH3)(1‐MeC)]2+ and trans‐[Pt(H2O)2(NH3)(1‐MeC)]2+, display a rich chemistry in aqueous solution, which is dominated by extensive condensation reactions leading to μ‐OH‐ and μ‐(1‐MeC−‐N3,N4)‐bridged species and ready oxidation of Pt to mixed‐valence state complexes as well as diplatinum(III) compounds, one of which was characterized by X‐ray crystallography: h,t‐[{Pt(NH3)2(OH)(1‐MeC−‐N3,N4)}2](NO3)2⋅2 [NH4](NO3)⋅2 H2O. A combination of 1H NMR spectroscopy and ESI mass spectrometry was applied to identify some of the various species present in solution and the gas phase, respectively. As it turned out, mass spectrometry did not permit an unambiguous assignment of the structures of +1 cations due to the possibilities of realizing multiple bridging patterns in isomeric species, the occurrence of different tautomers, and uncertainties regarding the Pt oxidation states. Additionally, compound 1 a was found to have selective and moderate antiproliferative activity for a human cervix cancer line (SISO) compared to six other human cancer cell lines.
Six, Seven or Eight Coordinate FeII, CoII or NiII Complexes of Amide‐Appended Tetraazamacrocycles for ParaCEST Thermometry
Authors: Olatunde Abiola O. , Bond Christopher J. , Dorazio Sarina J. , Cox Jordan M. , Benedict Jason B. , Daddario Michael D. , Spernyak Joseph A. , Morrow Janet R.
Published: October 2015

FeII, CoII and NiII complexes of two tetraazamacrocycles (1,4,8,11‐tetrakis(carbamoylmethyl)‐1,4,8,11‐tetraazacyclotetradecane (L1) and 1,4,7,10‐tetrakis(carbamoylmethyl)‐1,4,7,10‐tetraazacyclododecane (L2) show promise as paraCEST agents for registration of temperature (paraCEST=paramagnetic chemical exchange saturation transfer). The FeII, CoII and NiII complexes of L1 show up to four CEST peaks shifted ≤112 ppm, whereas analogous complexes of L2 show only a single CEST peak at ≤69 ppm. Comparison of the temperature coefficients (CT) of the CEST peaks of [Co(L2)]2+, [Fe(L2)]2+, [Ni(L1)]2+ and [Co(L1)]2+ showed that a CEST peak of [Co(L1)]2+ gave the largest CT (−0.66 ppm oC−1 at 4.7 T). NMR spectral and CEST properties of these complexes correspond to coordination complex symmetry as shown by structural data. The [Ni(L1)]2+ and [Co(L1)]2+ complexes have a six‐coordinate metal ion bound to the 1‐, 4‐amide oxygen atoms and four nitrogen atoms of the tetraazamacrocycle. The [Fe(L2)]2+ complex has an unusual eight‐coordinate FeII bound to four amide oxygen atoms and four macrocyclic nitrogen atoms. For [Co(L2)]2+, one structure has seven‐coordinate CoII with three bound amide pendents and a second structure has a six‐coordinate CoII with two bound amide pendents.
Redox‐Robust Pentamethylferrocene Polymers and Supramolecular Polymers, and Controlled Self‐Assembly of Pentamethylferricenium Polymer‐Embedded Ag, AgI, and Au Nanoparticles
Authors: Gu Haibin , Ciganda Roberto , Castel Patricia , Vax Amélie , Gregurec Danijela , Irigoyen Joseba , Moya Sergio , Salmon Lionel , Zhao Pengxiang , Ruiz Jaime , Hernández Ricardo , Astruc Didier
Published: October 2015

We report the first pentamethylferrocene (PMF) polymers and the redox chemistry of their robust polycationic pentamethylferricenium (PMFium) analogues. The PMF polymers were synthesized by ring‐opening metathesis polymerization (ROMP) of a PMF‐containing norbornene derivative by using the third‐generation Grubbs ruthenium metathesis catalyst. Cyclic voltammetry studies allowed us to determine confidently the number of monomer units in the polymers through the Bard–Anson method. Stoichiometric oxidation by using ferricenium hexafluorophosphate quantitatively and instantaneously provided fully stable (even in aerobic solutions) blue d5 FeIII metallopolymers. Alternatively, oxidation of the PMF‐containing polymers was conducted by reactions with AgI or AuIII, to give PMFium polymer‐embedded Ag and Au nanoparticles (NPs). In the presence of I2, oxidation by using AgI gave polymer‐embedded Ag/AgI NPs and AgNPs at the surface of AgI NPs. Oxidation by using AuIII also produced an AuI intermediate that was trapped and characterized. Engineered single‐electron transfer reactions of these redox‐robust nanomaterial precursors appear to be a new way to control their formation, size, and environment in a supramolecular way.
Dioxygen‐Mediated Decarbonylative CH Alkylation of Heteroaromatic Bases with Aldehydes
Authors: Paul Subhasis , Guin Joyram
Published: October 2015

An operationally simple and economical method for the direct alkylation of heteroaromatic bases employing readily available aldehydes as alkyl radical precursors and molecular oxygen as a reagent is presented. This simple transformation demonstrates a broad substrate scope with respect to aldehydes and nitrogen heterocycles, enabling the introduction of several medicinally important yet challenging alkyl moieties, such as ethyl, isopropyl, tert‐butyl, and cyclohexyl to the different classes of heterocyclic bases in good to excellent yields.
3‐Amidocoumarins as Potential Multifunctional Agents against Neurodegenerative Diseases
Authors: Matos Maria João , Rodríguez‐Enríquez Fernanda , Borges Fernanda , Santana Lourdes , Uriarte Eugenio , Estrada Martín , Rodríguez‐Franco María Isabel , Laguna Reyes , Viña Dolores
Published: October 2015

Monoamine oxidase (MAO) generates reactive oxygen species (ROS), which cause neuronal cell death, causing neurodegeneration. Agents that are able to concurrently inhibit MAO and scavenge free radicals represent promising multifunctional neuroprotective agents that could be used to delay or slow the progression of neurodegenerative diseases. In this work, variously substituted 3‐amidocoumarins are described that exert neuroprotection in vitro against hydrogen peroxide in rat cortical neurons, as well as antioxidant activity in a 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH⋅) radical scavenging assay. Selective and reversible inhibitors of the MAO‐B isoform were identified. Interestingly, in the case of the 3‐benzamidocoumarins, substitution at position 4 with a hydroxy group abolishes MAO‐B activity, but the compounds remain active in the neuroprotection model. Further evaluation of 3‐heteroarylamide derivatives indicates that it is the nature of the heterocycle that determines the neuroprotective effects. Evaluation in a parallel artificial membrane permeability assay (PAMPA) highlighted the need to further improve the blood–brain barrier permeability of this compound class. However, the compounds described herein adhere to Lipinski′s rule of five, suggesting that this novel scaffold has desirable properties for the development of potential drug candidates.
Fish consumption as a driver of risk-management decisions and human health–based water quality criteria
Authors: Judd Nancy , Lowney Yvette , Anderson Paul , Baird Suzanne , Bay Steven M. , Breidt Jay , Buonanduci Michele , Dong Zhao , Essig Don , Garry Michael R. , Jim Rebecca C. , Kirkwood Gemma , Moore Shelly , Niemi Cheryl , O'Rourke Rory , Ruffle Betsy , Schaider Laurel A. , Vidal-Dorsch Doris E.
Published: October 2015

The use and interpretation of fish consumption surveys and interviews, the application of fish consumption rates for sediment evaluation and cleanup, and the development of human health water quality criteria (HH WQC) are complex and interrelated issues. The present article focuses on these issues using examples from the United States, although the issues may be relevant for other countries. Some key considerations include the fact that there are many types of fish consumption surveys (e.g., 24-h recall surveys, food frequency questionnaires, creel surveys), and these surveys have different advantages and limitations. Identification of target populations for protection, identification of the species and quantities of fish consumed, and determination of bioaccumulation assumptions are important factors when developing water quality and sediment screening levels and standards. Accounting for the cultural importance of fish consumption for some populations is an even more complex element. Discussions about HH WQC often focus only on the fish consumption rate and may not have broad public input. Some states are trying to change this through extensive public participation efforts and use of probabilistic approaches to derive HH WQC. Finally, there are limits to what WQC can achieve. Solutions beyond the establishment of WQC that target toxics reduction from other sources may provide the greatest improvements to water quality and reductions in human health risks in the future. Environ Toxicol Chem 2015;34:2427–2436. © 2015 SETAC