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One of the most common methodologies of introducing extrinsic healing property to a polymer composite involves inclusion of healant-loaded microcapsules in the formulation prior to curing. In this paper,we discuss an analytical model for predicting the amount of healant released due to microcapsule rupture. Of particular interest is to understand the role of internal microstructure in the context of extrinsic healing. In microcapsules possessing “reservoir” type microstructure, the healant exists as a single droplet, and the entire contents are released upon rupture. On the other hand, in monolithic microcapsules, the healant is dispersed in the form of discrete micro-droplets, and depending upon the micro-droplet dimensions, significantly lower amount of healant is released in comparison to reservoir microcapsules. For the purpose of validation, composites were prepared using epoxy encapsulated microcapsules with varied internal structures. In line with our predictions, the extent of healing was much lower in the case of samples containing monolithic microcapsules. At 20% w/w microcapsule loadings, healing efficiencies close to 60% was observed upon introduction of reservoir type microcapsules, while under similar loadings, only 10% healing could be evidenced in the presence of monolithic microcapsules.

Актуальность работы. Значительная доля разрабатываемых нефтяных активов, приуроченных к карбонатным сложнопостроенным объектам, заметно возросла как на территории России, так и в Пермском крае. Достоверное знание параметров трещинно-порового типа коллектора позволяет уточнить действующие геолого-гидродинамические модели, подобрать рациональную систему разработки, регулировать процессы разработки и обеспечить для данного пласта оптимальные геолого-технические мероприятия. При построении и адаптации геолого-гидродинамических моделей нефтяных месторождений, особенно относящихся к сложнопостроенным карбонатным коллекторам, важное значение имеет знание как горизонтальной, так и вертикальной проницаемости (параметра анизотропии). При создании геолого-гидродинамических моделей карбонатных объектов месторождений Пермского края зачастую вертикальную проницаемость принимают равной нулю, хотя это далеко не так. Определение вертикальной проницаемости (параметра анизотропии), ее динамика при изменении пластового и забойного давлений и использование в геолого-гидродинамических моделях является актуальной задачей, которая позволит повысить качество и достоверность использования цифровых моделей для расчета и прогнозирования процесса добычи нефти. Цель: совершенствование геолого-гидродинамических моделей с учетом использования показателя анизотропии проницаемости. Объект: карбонатная фаменская залежь Гагаринского месторождения. Методы: обработка данных геолого-промысловых исследований; использование гидродинамического симулятора Tempest версии 8.3.1 компании Roxar. Результаты. По предложенной в статье методике определения параметра анизотропии обработаны 252 исследования, проведенные на добывающих и нагнетательных скважинах фаменской залежи Гагаринского месторождения. Для каждой литолого-фациальной зоны построена зависимость показателя анизотропии проницаемости от забойного давления. Для прогнозирования и оценки эффективности применяемых геолого-технических мероприятий и технологических показателей разработки авторами статьи модифицирована геолого-гидродинамическая модель с учетом полученных зависимостей об изменении параметра анизотропии. С помощью модифицированной гидродинамической модели удалось значительно улучшить адаптацию как по добывающим, так и по нагнетательным скважинам. Таким образом, повысилось качество и достоверность цифровой модели фаменской залежи Гагаринского месторождения для расчетов и прогнозирования процесса добычи нефти. The relevance of the research. A significant share of the developed oil assets, confined to carbonate complex objects, has increased markedly both in Russia and in the Perm Krai. Reliable knowledge of the parameters of a fracture-porous reservoir type allows selecting a rational development system, controlling development, ensuring optimal geological and technical measures for a given reservoir, clarifies the existing geological and hydrodynamic models. When building and adapting geological and hydrodynamic models of oil fields, especially those related to complex carbonate reservoirs, knowledge of both horizontal and vertical permeability (anisotropy parameter) is important. In practice, the vertical permeability in geological and hydrodynamic models is often assumed to be zero, although this is far from the case. Determining the vertical permeability (anisotropy parameter), its dynamics when changing reservoir and bottomhole pressures, and use in geological and hydrodynamic models is an important task that will improve the quality and accuracy of using digital models for calculating and predicting oil production. The main aim of the study is to improve the geological and hydrodynamic model, taking into account the use of permeability anisotropy index. Object: carbonate Famennian deposit of the Gagarinsky field. Methods: processing of geological research data; use of the Tempest hydrodynamic simulator version 8.3.1 from Roxar. The results. According to the method for determining the anisotropy parameter proposed in the article, 252 studies at production and injection wells in the Famennian deposit of the Gagarinsky field were carried out. For each lithofacial zone, the dependence of the permeability anisotropy index on the bottomhole pressure was constructed. For forecasting and evaluating the effectiveness of the applied geological and technical measures and technological indicators of development, the authors modified the geological and hydrodynamic model taking into account the dependencies obtained on the change in the anisotropy parameter. With the help of a modified hydrodynamic model, we managed to significantly improve the adaptation of both production and injection wells. Thus, it was possible to improve the quality and reliability of the digital model of the Famennian reservoir of the Gagarinsky field for calculating and forecasting oil production.

In order to overcome the conductivity limitations of Ba–oxide cathodes, Ba dispenser cathodes with a conductive metal matrix were introduced in the 1950s. Different variants of Ba dispenser cathodes are presented, either of the impregnated or the reservoir type. The optimized versions allow DC current densities of up to 10 A/cm2 and lifetimes of more than 100,000 h. Due to their high reliability, they are the workhorse in a lot of applications, above all in different types of microwave tubes. Emission and lifetime models are presented and discussed.

In recent years, a great number of stratified reservoirs with edge water and complicated faults have been discovered in Niger. Gas cap reservoirs are typical and common among all the discovered oil-bearing blocks. Making efforts to achieve good development effects of this kind of reservoirs is of great significance for stable production of entire project. There are many factors influencing the development of gas cap reservoirs. Development of gas cap reservoirs with edge water and complicated faults are very difficult and challenging. Several problems including gas breakthrough, interlayer interference and rapid increase of gas–oil ratio are easy to occur. Taking G oilfield in Niger as an example, based on development mechanism of gas cap reservoir with edge water and complicated faults, single sand bodies are specified and reservoir type of sub-layers are detailed researched according to gas cap index. Development idea of oil production prior to gas production is put forward and reasonable oil recovery offtake rate is optimized. In addition, water injection parameters are optimized and development strategy of layer by layer is adopted to realize successively producing remaining oil between layers. Combined with reservoir numerical simulation research and practical production practice, when the initial offtake rate is around 2%, stable production period and recovery factor within contract period is relatively high; according to the gas cap index, different energy layers are divided and commingling production or interlayer interference with different energy should be avoided; when the pressure level drops down to 60–70% of initial state, converting oil production well in side low position to be water injection well is essential; lower E3 and E2 reservoirs are produced in the preliminary stage and later upper E1 reservoirs should be produced integrated with the production–injection well network improvement to ensure the stable production of the oilfield. Successful development of G oilfield provides valuable ideas and references for the effective development of other similar reservoirs in Niger.

Dam construction and fish culture can change the biogeochemical processes in river, yet their impact on the spectral properties of particulate organic matter (POM) remains to be studied. This was investigated in a reservoir-type river (Minjiang river, SE China) using absorption spectroscopy and fluorescence excitation-emission matrices-parallel factor analysis (EEMs-PARAFAC). Five fluorescent components were identified from POM with PARAFAC. Four components C1-C4 were affected by the seasonal variations of rainfall and runoff, indicating the influences of hydrological condition and terrestrial inputs. The Chlorophyll a concentration (Chl a) correlated significantly with the humic-like C3 (p 0.05) and the protein-like C4 (p 0.01), indicating phytoplankton was an important source of C3 and C4. The Chl a and fluorescence intensities of C3-C4 were higher in the fish culture zones than in other areas, and the absorption coefficient a

The resource potential, “fractured” reservoir, reservoir type and stimulation technology of Jurassic tight oil in central Sichuan basin were investigated. Based on the evaluation method of tight oil resource, the amount of oil resources of the five Jurassic layers were estimated at 1.6 billion tons, showing that the Jurassic oil resource potential in central Sichuan Basin is huge. Integrated analysis of static and dynamic data including core-description, thin section examination, well test and exploration show Jurassic reservoirs are fracture-pore reservoir with ultra-low porosity, super-low permeability, rather than single “fractured” reservoir believed before. Jurassic reservoirs are tight oil reservoir with the characteristics of near source charge and continuous distribution. The high-quality hydrocarbon source, reservoir with better physical properties and fracture are the main factors controlling tight oil enrichment. “Horizontal well + volume fracturing” of Shayi Member tight sandstone reservoir and the “horizontal well + fracture acidizing” for the Da'anzhai Member shell limestone reservoir have achieved good stimulation effect. Key words: Central Sichuan Basin, Jurassic, tight oil, resource potential, tight reservoir, enrichment rule, reservoir stimulation

Bulk gels are increasingly applied to alleviate the costly burden of excessive water production in mature oil fields. Practically, designs of new treatments are adopted from previous field projects conducted in analogous reservoirs. This case-finding procedure requires reservoir engineers to have thorough knowledge about how gel treatments, for each reservoir type, should be designed and have been mostly applied. This paper presents comprehensive design guidelines for injection-well gel treatments based on 61 worldwide field projects. It also assesses typical and most-applied designs and introduces them as new designing strategy. Seven gel strength design parameters were evaluated using the univariate descriptive analysis, stacked histograms, and scatterplots. Results indicated that gel strength parameters have very wide ranges and are considerably affected by the formation type. Gel treatments typically start with 3000 ppm polymer concentration, end with 7600 ppm, and a constant polymer-crosslinker ratio (PCR) of 40:1 is maintained during the treatments. They are often performed using the injection waters (to avoid type II gel syneresis) and polymers of 10–11 MM Da molecular weight (MW) and 30% hydrolysis that are injected in 4–5 treatment stages. The gel strength is principally designed based on the problem channeling strength and the planned gel volume. However, in cases of void-space-type problems, the gel extrusion, breakthrough, and breakdown become important designing criteria. To address these issues, more advanced tapering schemes than normal gradual increase of polymer concentrations are used to optimize gel plugging efficiency. In these schemes, small volumes of cement or low MW, fast-maturing, rigid gels (i.e., MARA-SEALTm) are injected in front (gels only) or behind the high-MW MARCIT℠ gels as capping-materials. The novelty of present review lies in providing conformance specialists with new design strategy that would markedly facilitate designing of gel treatments and save time needed to identify analogs for a given candidate reservoir.

Accurate and quantitative evaluation of low-permeability reservoirs and other more complex reservoirs not only depends on various control factors related to the reservoir but is also affected by our incomplete understanding of reservoirs and the imperfections inherent in evaluation methods. The evaluation of reservoirs may be improved by determining the integrity and uncertainty of the reservoir evaluation process and effectively examining the differences between evaluation results. Taking membership as the linking factor, utilizing the idea of information superposition, and combining the fuzzy comprehensive and gray relational evaluation methodologies in the uncertainty evaluation, this study presents a differentiated and improved internal algorithm and establishes a more effective fuzzy-gray comprehensive evaluation method. The example of E32 interval evaluation in the southern Nanbaxian gas field of the Qaidam Basin shows that this method not only considers the fuzziness and grayness related to reservoir evaluation but also provides improved discrimination of low-permeability reservoirs and increased accuracy in the reservoir description. According to the improved reservoir classification results, the E32 intervals are divided into four types of reservoirs, of which types I and II are favorable reservoirs. The lateral distribution of the reservoir is described in more detail than previously, with near-continuous knowledge, and there is a good distinction between the reservoir type. The obtained results are in line with the development rules of geological deposition and the geological knowledge base, approximately matching existing practical results and geological knowledge. This method can be used to quickly and effectively guide exploration and development strategies related to gas fields, and provides a new approach for low permeability and tight reservoir evaluation.

Natural gas hydrates mostly fill in the pores or fractures of host sediments and fractured gas hydrates are the main reservoir type in the Qilian mountain region of China. The process of gas production from hydrates can be influenced by the pore structures, fracture properties and mineral compositions of the host sediments. To determine whether the formation and phase equilibrium of hydrates are affected by the properties of the fractures, including the angle and width, formation experiments on methane hydrates were conducted using fracture media composed of artificial sandstone and natural mudstone. The phase equilibrium points for the methane hydrates hosted in fracture mudstone were measured using multi-stage heating. The experimental results indicate that the gas hydrates hosted within the fracture media grew faster. However, there were obvious differences in the methane hydrate formation morphologies for the two types of fracture media: the main occurrences of gas hydrates in sandstone were massive formations, and layered gas hydrates were formed along the fracture surfaces in mudstone. Additionally, a comparison of the phase equilibrium between the fractured CH4 and bulk phase CH4 hydrates indicated that the fracture scale did not have a significant influence on the thermodynamic equilibrium of the CH4 hydrates for the experimental conditions and also implied that fracture properties had an insignificant impact on the hydrate stability zone.

This study characterized the generation of windblown dust from various sources in the Athabasca Oil Sands Region (AOSR) in Alberta, Canada. The Portable In-Situ Wind Erosion Laboratory (PI-SWERL) equipped with two real-time dust monitors and nine-channel filter packs was used to simulate wind-driven erosion and measure emissions. Sixty four sites were measured, including oil sands mining facilities, quarry operations, and roadways in the vicinity of Ft. McMurray and Ft. McKay. Key parameters related to windblown dust generation were characterized including: threshold friction velocity, reservoir type, and particle size-segregated emission potential. The threshold wind speed for particle suspension varies from 11 to 21.5 km/h (u10+; measured at 10 m above ground level), and saltation occurs at higher speeds of u10+ >32 km/h. All surfaces have limited dust supplies at lower wind speeds of

To avoid big deviation in reserve estimation and make scientific and reasonable reserves to guide the exploration and development of fracture-cavity carbonate reservoirs, a new three-dimensional reservoir space description and reserve calculation method for layered, fracture-cavity carbonate reservoirs is used to calculate the reserves of X block in the Halahatang oilfield in the Tarim Basin. In the method, the reserve calculation parameters are worked out by quantitative spatial delineation based on high precision three-dimensional seismic data; the high confidence well-seismic inversion and sensitive attributes and threshold value are used jointly to delineate the oil-bearing area, effective thickness and effective porosity of the cavity, vug and fracture reservoirs. The reserves are calculated with the volumetric method, and the dynamic recovery of different types of reservoirs is calibrated by actual drilling data. This method is suitable for reserve estimation and development program making of fracture-cavity carbonate reservoirs with strong heterogeneity. Key words: Tarim Basin, fracture-cavity carbonate reservoir, reserve calculation, quantitative space delineation, dynamic recovery, reservoir type

The hydrocarbon reservoirs which have been found in SZ36-1 region are located in Liaoxi low uplift and dominated by structural traps. The principle source rock is the first and the third member of the Neogen Shahejie Formation and the main reservoir type is delta sand body which mainly located in the second member of Shahejie Formation. Oil reservoirs are mostly in normal pressure and are possess characteristic of late hydrocarbon accumulation. Hydrocarbon accumulation is mainly controlled by fault,reservoir-cap rock combination, and petroleum migration pathways. Lateral distribution of hydrocarbon reservoirs is mostly controlled by reservoir rocks, while the vertical distribution is controlled by fault.

The overall exploration and development degree of the Heidimiao potential oil layer in D block is not high, and there are still some problems in the development work, such as reservoir display law, oil-water layer identification and oil and water distribution prediction. In this paper, the distribution law of reservoir oil and water of Heidimiao oil reservoir in D block is studied by quantitative log interpretation combined with geological characteristics. The result showed that the permeability of reservoirs increases with the increase of lithological particles, the oil content of the reservoir becomes better as the size of rock particles increases. On the basis of the characteristics of the block reservoir type and the analysis of the main control factors of the logging response, the distribution of oil and water is more accurate and reliable.

This paper analyses the role of the principle of downstream benefit sharing under international water law regime in the management of cross-border water courses. This paper argues that the principle of downstream benefit sharing may play a key role in wiping away the long-existing distrust between countries as well as hold the potential to usher in a new phase of cooperation between riparian neighboring countries, such as Nepal and India. If pursued in good faith the downstream benefit principle would enjoin erstwhile losers of the vast potential to a cooperative mechanism where they could find themselves in a win-win situation. The Budhi Gandaki Storage Project presents a unique opportunity for employing this new paradigm of cooperation between two countries: Nepal and India. In this paper, we present the example of India that is facing a water and energy crisis for which it may ease to a considerable extent its problem by depending on Nepal for these resources. Downstream benefit sharing may provide India an opportunity to gain the confidence of the Nepalese people for developing many hydro projects with or without water augmentation resulting into multiple benefits downstream in India. Employing the downstream benefit sharing principle might requirere visiting treaties like Gandak Project Agreement.DOI: http://dx.doi.org/10.3126/hn.v14i0.11267HYDRO Nepal JournalJournal of Water, Energy and EnvironmentVolume: 14, 2014, JanuaryPage: 59-64

Reservoir Γ north, which belongs to Zhanzhol, Kazakhstan, a fracture-pore typed carbonate oilfield, has a variety of reservoir types. According to the combination pattern of different voids and the relationship between porosity and permeability, carbonate reservoirs are classified into four types which are fracture-cavity-pore typed (referred to as composite typed here after), fracture-pore typed, pore typed and fracture typed, and the identification of which by well logging data is realized. There is a little difference in the producing degree within the same reservoir type for composite typed and fracture typed reservoirs. However, there are large differences in the producing degree for fracture-pore typed and pore typed reservoirs. In order to appraise the producing degree of reservoirs more exactly, key parameters affecting the producing degree of fracture-pore typed and pore typed reservoirs are selected separately, which, for the fracture-pore typed are reservoir quality index (RQI), pore throat radius at mercury saturation of 50% (R50), total permeability (Kf+Km), and the ratio of fracture permeability to matrix permeability (Kf/Km), and for the pore typed are RQI, R50, and matrix permeability (Km). With the integrated consideration of matrix and fracture, a flow unit classification method for dual medium reservoir is established, and taking these parameters as clustering variants, four types of reservoirs are further divided into six kinds of reservoir flow units by the means of neural network clustering technology. Based on reservoir flow unit modeling, a numerical simulation model is built with each type of reservoir flow units adopting its corresponding relative permeability curve, based on which, the distribution regularity of remaining oil of reservoir Γ north is studied and demonstrated. Eight new wells are designed according to the research result, and put into production in 2013 with the initial daily oil production rate being 2.3 times that of nearby old wells. Key words: carbonate oil reservoir, reservoir type, reservoir flow unit, neural network clustering technology, reservoir flow unit model, remaining oil

The structural setting of Jurassic and lower Cretaceous in the hinterland area of Junggar basin is simple, underdeveloped in anticlinal traps, the petroleum accumulation has distal and secondary characteristics, complicated hydrocarbon distribution pattern makes the exploration there very difficult. Structural reservoirs predominated in the oil and gas fields discovered in early stages, and only 2 high yield nonstructural oil reservoirs – X21 and X31 were discovered on the southeastern slope of Jidong nose arch. No breakthrough has been made in either Jurassic or lower Cretaceous in the hinterland area over the past 10 years. Based on dissection on X31 reservoir, this paper ascertains once more the pay zone age, determines the reservoir type as stratigraphic one, and believes that the trap origin is related to the residual pre-Cretaceous palaeo-salient. This paper suggests paying attention to Jurassic and lower Cretaceous stratigraphic hydrocarbon reservoirs in the exploration of the hinterland area, especially focusing on fine depiction of pre-Cretaceous palaeogeomorphology and analysis on its controlling role in stratigraphic hydrocarbon reservoirs. Based on the “fill a gap” principle, the Qingshuihe Formation Member I thickness image is adopted to reflect the pre-Cretaceous palaeogeomorphology of the study area, whose basic features are as follows: 1 near NW – SE palaeo-trough is retained by 2 uplifted areas, different width of slope areas occur between the palaeo-trough and the palaeohighs, and 1 apparent topographic slope break zone developed in south central part. Comprehensive analysis suggests that stratigraphic traps are developed in the palaeo-salient of slope area and the slope break zone where the petroleum accumulation conditions are favorable, which are the favorable places for stratigraphic hydrocarbon reservoir exploration.

A set of surface equipment for monitoring the parameters of fluid and pressure while drilling was developed, and mathematical models for gas reservoir seepage and wellbore two-phase flow were established. Based on drilling operation parameters, well structure and monitored parameters, the wellbore pressure and the gas reservoir permeability could be predicted theoretically for underbalanced horizontal drilling. Based on the monitored gas production along the well depth, the gas reservoir type could be identified.

The research on Putaohua oil layer in Taidong,Songliao Basin using core,logging and seisimic information shows that oil is divided into belts from east to west influenced by faults striking from south to north and oil potential is getting poorer from east to west, oil is mainly distributed in the middle of Putaohua oil layer showing double peaks, and the main reservoir type is fault-lithology reservoir formd by NStrending faults and NW trending channel sandbody on the slope dipping to the southeast. According to the match type between fault and sandbody in single trap ,we draw the accumulation law that oil accumulation area is controlled by single fault-terrace belt; the high-quality reservoir is composed of underwater distributary channel and river sheet sand; vertical oil accumulation height is influenced by fault lateral sealing ability; and oil accumulation horizon is controlled by the match type between fault and sandbody.

Many solid transdermal formulations have been developed over the last several decades. These formulations can be classified according to various angles. With respect to water content in the formulation, the non-aqueous solid formulations are called dermal patches or plasters, and the aqueous solid formulations are classified as cataplasms. Similarly, the classification into reservoir type and matrix type can be done from the aspect of patch configuration. This chapter summarizes the various patch formulations already marketed in several countries and provides the basic components and compositions of these formulations.

Bootstrap reservoir type Pressurized system is designed to maintain the return pressure in the reservoir to ensure the pumps working without cavitation. Different pressurized systems for the bootstrap reservoirs are analyzed and then the hydraulic type pressurized system for the civil aircraft hydraulic reservoir is selected and designed. Then the bootstrap pressure, pressure maintaining time, assistant flow capacity of the selected hydraulic type bootstrap reservoir is simulative calculated. Finally, the EDP restarting and full flow working profile is used to confirm the designed hydraulic type bootstrap pressurized system is confirmed to be suitable of the civil aircraft system.

Based on lots of previous studies, the unconformity structure characteristics were studied and the controlling effect of unconformity structure on hydrocarbon reservoir, migration path and oil-gas reservoir type were analyzed. The result shows that the unconformity structure is composed of upper basal conglomerate layer, lower weathering clay layer and semi-weathering rock; the interlocking pores in basal conglomerate layer and pore-cave-fracture system in semi-weathering rock are the main storage space of hydrocarbon reservoir; And hydrocarbon migrates laterally through capillary “channeling effect” in interlocking pores, and the pore-cave-fracture system in semi-weathering rock is an important path for hydrocarbon migration laterally and vertically; stratigraphic overlap hydrocarbon reservoir and stratigraphic unconformity reservoir are the two type of reservoirs related to unconformity, and buried hill reservoir is an important type of the latter.

Based on the twenty years’ hydrologic data and water quality materials from the year 2005 to 2010, this article studies the water environment changes of reservoir type water source and the water quality protection countermeasures. Through the analysis, it founds that, with the increase of the rainfall, voluminous non-point source pollution was brought to water. The increase of rainfall runoff influences differently to the reservoir's major pollutants -TN and TP. The increase of the rainfall runoff has a dilute effect on TN; with the increase of the rainfall runoff, the TP threshold will increase.

Due to the severity of impacts predicted due to climate change issues, Greenhouse Gas (GHG) emissions need to be considered as a factor even for hydropower because of the identified emission possibilities associated with large reservoirs. Thus, when planning a large hydropower project at a selected location, it is important to decide on the type of power plant based on an economic comparison including environmental considerations. The existing 150MW, Talawakele run of the river type hydropower plant and the previously planned reservoir type Caledonia hydropower plant were selected for comparison in this study. Net greenhouse gas emissions from both projects were estimated based on several estimating techniques and for the economic comparison, the levelized cost of electricity of both projects were calculated. Results show that the unit cost of electricity generation from run of the river type is substantially lower (around LKR 4 per kWh) than that of reservoir type. On the other hand, as Upper Kotmale is a peak-serving plant, a separate comparison was done considering the night peak operation. Results show a loss to the country (around LKR 2 billion per year) by energy reduction due to not implementing the reservoir type Caledonia hydropower plant. It is concluded that for future large hydropower developments in the world, a similar study should be carried out before deciding to downsize the reservoir. The study has further concluded that GHG emission considerations are not strong enough to discourage reservoir type new hydropower plant developments.

The basic objective of this study was to develop a novel technique that aids in compaction of coated pellets into tablets and obtain a release pattern from compressed pellets resembling the same pattern before compression.Multi-unit dosage forms of mesalamine targeted to the colon were formulated by extrusion-spheronization, and then coated with Eudragit S (30%). These pellets were filled into gelatin capsules or further formulated and compressed into tablets. Tablets for colonic delivery of mesalamine were prepared by mixing the coated beads with cushioning agents like stearic acid and Explotab, or by applying an additional coat of gelatin (4% weight gain) onto the Eudragit S coated pellets, and then compressing into tablets (tableted reservoir-type pellets). Then additional coating of the tablets prepared by the coating technique was applied utilizing Eudragit L 100-55 (5% weight gain).This technique provides additive protection for the coated beads to withstand the compression force during tableting. Excellent in vitro dissolution results were obtained, which were comparable to the results of the release of mesalamine from uncompressed beads filled in capsules. Mesalamine release from the capsules was 0.3% after 2 hours in gastric pH, 0.37% was released after an additional 1 hour in pH 6, and 89% was released after 1.5 hours in colonic pH 7.2.Various formulation and process parameters have to be optimized in order to obtain tableted reservoir-type pellets having the same release properties as the uncompressed pellets. The coating technique delays the release of mesalamine until the beads reach the terminal ileum and colon. Once released in the colon, mesalamine is minimally absorbed and can act locally to treat ulcerative colitis.

Note: [1046] Reference EPFL-ARTICLE-213125doi:10.1061/(ASCE)HY.1943-7900.0000780View record in Web of Science Record created on 2015-10-21, modified on 2016-08-09

A new microencapsulation technique based on the solvent exchange method was implemented using an ultrasonic atomizer system to encapsulate a protein drug in mild conditions. The reservoir-type microcapsules encapsulating lysozyme as a model protein were prepared by inducing collisions between the aqueous droplets containing lysozyme and the droplets of organic solvent with dissolved poly(lactic acid-co-glycolic acid) (PLGA). The main focus of the study was to examine formulation variables on the size and the encapsulation efficiency of the formed microcapsules. The formulation variables examined were concentrations of mannose in the aqueous cores, NaCl in the aqueous collection medium, and PLGA in organic solvent. The mean diameter of the microcapsules ranged from 40 microm to 100 microm. Smaller microcapsules showed lower encapsulation efficiencies. The resulting microcapsules released native lysozyme in a sustained manner, and the release rate was dependent on the formulation conditions, such as the concentration and molecular weight of the polymer used. The solvent exchange method does not induce lysozyme aggregation and loss of its biological activity. The solvent exchange method, implemented by the ultrasonic atomizer system, provides an effective tool to prepare reservoir-type microcapsules for delivering proteins.

The purpose of this reseach was to characterize and optimize the properties of microcapsules produced by the solvent exchange method, a new microencapsulation technique. Reservoir-type microcapsules containing lysozyme as a model protein were produced using a coaxial ultrasonic atomizer under various formulation and instrument settings, and characterized with respect to in vitro release kinetics and stability of the encapsulated protein. The solvent exchange method could encapsulate protein drugs with high efficiency under an optimized condition and was mild enough to preserve the integrity of the encapsulated lysozymes during the process. In vitro release studies showed that the microcapsules could release proteins in a controllable manner. The solvent exchange method is a mild and simple microencapsulation method that could encapsulate lysozyme, maintaining its functional integrity.

Residual Al contents were measured in Fe- and Ni-base alloys in order to improve lifetime prediction models based on the consumption of the Al reservoir. Measurements were made using electron probe microanalysis (EPMA) on both foil (50–125 μm thickness) and plate (0.5–2mm) material. For FeCrAl, NiCrAl and Fe3Al plate specimens, significant Al concentration gradients were measured. An Al gradient is not considered in current reservoir type models. Residual Al contents at the onset of breakaway oxidation were somewhat lower than previously reported for several FeCrAl alloys and significantly higher (»10at.%) for Fe3Al and Fe–Al alloys. The implications of these results for performance and lifetime predictions are discussed.

We report on recent work to produce a small low power, low cost reservoir cathode capable of long life (more than 100,000 hours) at high loading (> 5 A/sq cm). Our objective is a highly manufacturable, commercial device costing less than $30. Small highly loaded cathodes are needed, especially for millimeter wave tubes, where focusing becomes difficult when area convergence ratios are too high. We currently have 3 models ranging from .060-inch diameter to. 125-inch diameter. Reservoir type barium dispenser cathodes have a demonstrated capability for simultaneous high emission density and long life. Seven reservoir cathodes continue to operate on the cathode life test facility at NSWC, Crane, Indiana at 2 and 4 amps/sq cm. They have accumulated nearly 100,000 hours with practically no change in emission levels or knee temperature.

Detailed hydrodynamic models are very important tools for various types of water management activities. For trans boundary basins or basins covering catchments managed by different authorities, different types of models may be applied, which will lead to problems of compatibility and, hence, complicate the integrated catchment modelling and management process. Another problem are the huge calculation times. A possible solution for this problem lies in the transformation of the existing detailed models into conceptual reservoir-type models, with an explicit calculation scheme. This approach does not only simplify the process of model integration, but does also achieve an important reduction of the model calculation times. However, one well-known problem is that conceptual models have difficulties to account for backwater effects. For this reason, their application to tidally influenced river reaches so far was non-existent. This paper introduces an extension of the existing grey-box reservoir modelling technique to incorporate tidally influenced river reaches. The presented methodology is demonstrated for the downstream part of the rivers Zenne and Rupel in Belgium. Calibration of the grey-box model was done based on the results of a detailed hydrodynamic model that solves the full de Saint-Venant equations. Results show a minor loss of accuracy when the detailed model is replaced by the surrogate conceptual model. Also, the tidal effects are well represented.

To further improve landslide deformation prediction accuracy in Three Gorges reservoir, near-real-time monitoring systems were built in the subsequent phase of Three Gorges Project to substitute early manual monitoring. Shuping landslide, a typical reservoir type slide, is taken as an example; the near-real-time monitoring system that includes field continuous Global Positioning System (GPS) sensors, communication infrastructure, and control center is described first. Then, based on the near-real-time monitoring data from June 20, 2012, to June 30, 2013, the spatial and temporal moving patterns are analyzed. Finally, by comparing the displacements to reservoir water fluctuation and rainfall, the conclusion is that landslide deformation is mainly triggered by the fast reservoir water level fall, and rainfall has a secondary influence. The results indicate that near-real-time monitoring can greatly improve the precision of understanding landslide behavior and the relation between movement and inducing hydrologic factors, which would be critical to protecting lives and property.

We have assessed the performance of the Hudson-type mask without reservoir and the Hudson non-rebreathing mask with reservoir bag in 10 pregnant and 10 non-pregnant women at different oxygen flow rates by measuring end-expired oxygen fraction (FEO(2)). The Hudson mask without reservoir behaved similarly in pregnant and non-pregnant women, providing a mean FEO(2) of 0.32 with oxygen flow of 4 L.min(-1) which increased to 0.46 at 15 L.min(-1). The reservoir mask produced a lower FEO(2) in pregnant subjects than in non-pregnant subjects, with a mean FEO(2) of 0.33 and 0.64 at 4 L.min(-1) and 15 L.min(-1) in pregnant subjects compared to 0.44 and 0.72, respectively, in non-pregnant women. Neither mask delivers the expected maximum inspired oxygen fraction quoted by its manufacturer, assuming that inspired oxygen fraction quoted by its manufacturer, assuming that inspired oxygen fraction is 0.06 higher than expired and correcting for humidification of inhaled gases within the respiratory tract. The importance of these findings in the care of the obstetric patient and the treatment of acute fetal hypoxia is discussed.

Enhanced (or engineered) geothermal systems (EGS) have evolved from the hot dry rock concept, implemented for the first time at Fenton Hill in 1977. This paper systematically reviews all of the EGS projects worldwide, based on the information available in the public domain. The projects are classified by country, reservoir type, depth, reservoir temperature, stimulation methods, associated seismicity, plant capacity and current status. Thirty five years on from the first EGS implementation, the geothermal community can benefit from the lessons learnt and take a more objective approach to the pros and cons of ‘conventional’ EGS systems.

Spherical microporous reservoir type microcapsules composed of P(HB-HV) (10·8% HV)/20% PCL containing BSA (surrogate protein) loaded agarose have been fabricated using a double emulsion technique with solvent evaporation. Microcapsules were generated in high yield (> 75 wt%) and BSA incorporation had no significant effect on microcapsule size distribution (21–200 μm). The loss of BSA both by partitioning into the aqueous continuous phase, and through micropores as BSA-loaded-agarose during the precipitation of the fabrication polymer concomitant with solvent evaporation, resulted in low encapsulation efficiency (12%). The amount and duration of BSA release was influenced as much by micropore numbers and diameter as by the extent of reservoir loading and detectable levels of BSA release could be monitored for up to 24 days.

The objective of the present study was to investigate if temperature can be utilized to accelerate drug release from Nuvaring®, a reservoir type intravaginal ring based on polyethylene vinyl acetate copolymer that releases a constant dose of contraceptive steroids over a duration of 3 weeks. The reciprocating holder apparatus (USP 7) was utilized to determine real-time and accelerated etonogestrel release from ring segments. It was demonstrated that drug release increased with increasing temperature which can be attributed to enhanced drug diffusion. An Arrhenius relationship of the zero-order release constants was established, indicating that temperature is a valid parameter to accelerate drug release from this dosage form and that the release mechanism is maintained under these accelerated test conditions. Accelerated release tests are particularly useful for routine quality control to assist during batch release of extended release formulations that typically release the active over several weeks, months or even years, since they can increase the product shelf life. The accelerated method should therefore be able to discriminate between formulations with different release characteristics that can result from normal manufacturing variance. In the case of Nuvaring®, it is well known that the process parameters during the extrusion process strongly influence the polymeric structure. These changes in the polymeric structure can affect the permeability which, in turn, is reflected in the release properties. Results from this study indicate that changes in the polymeric structure can lead to a different temperature dependence of the release rate, and as a consequence, the accelerated method can become less sensitive to detect changes in the release properties. When the accelerated method is utilized during batch release, it is therefore important to take this possible restriction into account and to evaluate the accelerated method with samples from non-conforming batches that are explicitly "out of specification" under real-time test conditions.

Regional environmental risk assessment of drinking-water source is considered a very effective way for us to find out the security situation and hidden danger of Drinking-water source and to discriminate the high-quality drinking-water sources for differentiated management. In this paper, reservoir type drinking-water source is selected as the object of assessment. An index system consisted of 2 parts (pollutant risk assessment index system and risk-resisting ability assessment index system) is built to qualitative and semi-quantitative evaluate. We sort out a pollutant source list which is suitable for China and at last established a practical regional environmental risk assessment method. Two reservoir-type water sources in Zhejiang Province are selected as the objects for case application. Assessment results shows that this method can discriminate the drinking-water source by the value of regional environmental risk clearly.

Installation of large-scale compressed air energy storage (CAES) plants requires underground reservoirs capable of storing compressed air. In general, suitable reservoirs for CAES applications are either porous rock reservoirs or cavern reservoirs. Depending on the reservoir type, the cyclical action of air injection and subsequent withdrawal produces temperature and pressure fl uctuations within the reservoir. An accurate prediction of these fl uctuations is essential for the design of the reservoir and its associated turbomachinery. Being mutually dependent, the selection of the turbomachinery and reservoir characteristics must be conducted simultaneously to obtain an integrated cost-effective plant. The present review is intended to encompass the pertinent literature on the temperature and pressure variations within CAES reservoirs. The principal experimental and operational data sources are described, as well as important results of theoretical modeling efforts. Conclusions derived from those investigations and their relevance to CAES plant designs are discussed.

Summary A comprehensive numerical simulation study showed that for a typical heavy-oil reservoir, steamflood performance improves monotonically with increases in steam quality and injection rate. Hence, for this reservoir, the optimum quality and injection rate are the highest values that were investigated. In general, however, optimum steam conditions depend on reservoir type and operating mode (e.g., line drive or pattern flood). For most situations, published "rule-of-thumb" steam conditions are not optimum. Therefore, we recommend that optimum steam conditions for a specific reservoir be determined through economic comparison of predicted oil recoveries for ranges of steam conditions, as demonstrated in this study.

Megaplatypus mutatus (=Platypus mutatus) is an ambrosia beetle native to South America. Unlike most ambrosia beetles, it attacks only living trees, penetrating the xylem of its host by boring long tunnels. These galleries cause severe stem-breakage and mortality in commercial poplar plantations.In previous studies we showed that volatile emissions from pioneer male M. mutatus are composed of (+)-6-methyl-5-hepten-2-ol, 6-methyl-5-hepten-2-one and 3-pentanol. Recently, we developed reservoir type controlled release dispensers and tested the efficacy of various trap designs in the field. Results showed that black cross-vane traps (CIPEIN-CV) captured significantly more insects than other traps designs baited with the same dispensers. In the present study we modified the colour, the construction material and the size of traps with the aim of increasing trapping efficacy and reducing the final trap cost. The results showed that significantly more female and male M. mutatus were captured in small and large traslucent traps (CIPEIN-CVt) than in black CIPEIN-CV trap. Furthermore, traslucent CIPEIN-CVt trap costs were significantly lower than costs for CIPEIN-CV traps. Significantly improved trapping efficacy with an important decrease in final costs will allow detection of considerably lower populations of M. mutatus in monitoring programs. © 2011 Elsevier Ltd. Fil: Gonzalez Audino, Paola Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; Argentina. Universidad Nacional de San Martín; Argentina Fil: Gatti, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; Argentina Fil: Zerba, Eduardo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas para la Defensa. Centro de Investigación de Plagas e Insecticidas; Argentina. Universidad Nacional de San Martín; Argentina

Publisher Summary This chapter examines the elements of screening that are required to make progress with decision making. Three screening styles must usually be combined to take a calculated decision of enhanced oil recovery (EOR). The first one, conventional screening, is the one most engineers are familiar with, and it is usually carried out by comparing average reservoir properties with data in a look-up table that contains validity limits for each parameter considered important. Geologic screening is a way of looking at the reservoir type in terms of heterogeneity, connectivity, and other geologic characteristics that have been found to be important in managing risk or that correlate with process performance. If a field or reservoir under consideration presents enough commonalities with field experiences in the same area or elsewhere. If the answer is positive, then the likelihood of finding referential information as to what the course of action was in similar reservoirs can be investigated; if, on the other hand, the reservoir under evaluation turns out to be an exceptional case with no comparable field conditions in EOR, care must be exercised to avoid excessive risk in the application of an EOR process.