bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Rheological Properties of Oil-Based and KCl Drilling Fluids
Authors: Werner Benjamin , Lund Bjørnar , Myrseth Velaug , Saasen Arild , Gyland Knud Richard
Published: March 2016

One of the main tasks of drilling fluids is to transport cuttings to the surface to clean the borehole. During this process the fluid is exposed to different flow regimes, shear rates and temperatures. The fluid properties affect the flow behavior, where viscosity, density and gel strength are among the key parameters. Field experience indicates that oil-based drilling fluids perform better in terms of hole cleaning than water-based fluids do, even if viscosity and density values are similar. The exact reasons for this are not entirely understood and increased knowledge will contribute towards more efficient drilling operations.

To deepen the understanding of the hole-cleaning abilities of drilling fluids, a comparative study with oil-based and water-based drilling fluids with similar viscosity profiles was executed. Flow-loop experiments in a 10 m long test section with a free-whirling rotating inner drill string are correlated to rheological investigations on a Fann 35 viscometer and an Anton Paar rheometer. The Fann 35 measurements follow the ISO/API standards and include viscosity and gel-strength measurements. With the Anton Paar rheometer flow curves and temperature dependence were obtained.

This paper presents selected rheological properties in correlation to flow-loop experiments in order to get a better understanding of the unequal behavior in solids transport of the two drilling fluid types. The presented results include yield point and plastic viscosity determination. In addition Herschel-Bulkley and power-law regressions were used to obtain comparable yield-point values. The rheometer measurements provide more detailed data due to extended functionality of the instrument, higher accuracy for each measuring point and a higher number of data points acquired compared to the Fann viscometer.

The yield point of the fluids is expected to influence mainly the static and the low-flow conditions in the wellbore, whereas the plastic viscosity may have more importance in the high-shear region of the flow. To draw back conclusions from the rheology measurements to the flow-loop results, these two points are highlighted in this study.
Sagebrush ingestion by lambs: Effects of experience and macronutrients
Authors: Burritt E. A. , Banner R. E. , Provenza F. D. ,   Society for Range Management
Published: March 2016

We investigated how experience early in life and macronutrient content of the diet influenced intake of mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana (Rydb.) Beetle) by sheep. In the first part of our study, 2-month-old lambs were exposed as a group for 2 mo to a 70% barley-30% soybean meal ration (300 g/hd/day) that contained increasing amounts sagebrush (1 to 20%). Control lambs received grain without sagebrush. All lambs had access to alfalfa hay and pellets ad libitum. When lambs were tested at 6 months of age, prior exposure had no effect on sagebrush consumption after the first 4 days of the trial. When sagebrush comprised 20% of an alfalfa/barley ration, lambs ate the sagebrush ration readily even when a nutritious alternative was offered indicating the flavor of sagebrush did not prevent lambs from feeding. Increasing the amount of sagebrush in the ration from 50% to 75% resulted in lambs eating less of the barley/sagebrush ration, but daily intake of sagebrush remained constant throughout the 4 day trial, presumably because toxins (terpenes) limited intake of sagebrush. In the second part of our study, lambs experienced with sagebrush were fed 250 g/hd/day of barley, and nutritional status was varied by offering alfalfa pellets at 33% or 80% of ad libitum (1.2 and 2.7 times maintenance, respectively) to determine if dietary energy levels affected intake of sagebrush. Each day lambs received a 50/50 sagebrush/barley supplement ad libitum for 1 hour. Lambs fed at 33% of ad libitum consumed more of the sagebrush/barley supplement than lambs fed at 80% of ad libitum. Thus, additional energy did not enable lambs to consume more sagebrush. In the last trial, lambs in both treatments were fed a basal ration of alfalfa pellets at 50% of ad libitum. Each morning for 1 hour, lambs were offered macronutrient supplements containing either 50% barley/50% sagebrush (high energy) or 25% barley/25% soybean meal/50% sagebrush (high energy and protein). Lambs consumed the same amount of sagebrush regardless of supplement. Thus, supplemental protein did not improve sagebrush consumption. We conclude lambs readily ingested a high-energy ration containing sagebrush, regardless of exposure early in life, suggesting toxins, not flavor, control intake of sagebrush. Further, supplementing lambs with energy or protein failed to improve intake of sagebrush, which suggests these macronutrients did not enhance detoxification of sagebrush.
Residual nitrogen effects on soil, forage, and steer gain
Authors: Berg W. A. , Sims P. L. ,   Society for Range Management
Published: March 2016

Nitrogen fertilization is a common practice on introduced grass pastures established on marginal farmland in the Southern Great Plains. The efficiency of N fertilizer use on pastures and concern about nitrate movement into substrata prompted this study of residual N effects following fertilization. The study was conducted on Old World bluestem (Bothriochloa ischaemum L.) pastures on Pratt soil (sandy, mixed thermic Psammentic Haplustalfs) in western Oklahoma where the 57-year average annual precipitation is 566 mm yr(-1). Herbage production and steer gains were quantified over 3 summer grazing seasons on paddocks fertilized annually with 0, 34, 68, or 102 kg N ha(-1) yr(-1) during the preceding 5 years. Peak standing ungrazed herbage yields were 2- to 4-fold greater in paddocks fertilized the preceding 5 years and were linearly related to the total N applied the previous 5 years. Steer weight gain responded linearly to N with an average of 0.63 kg gain over 3 years per kg N applied over the preceding 5 years. No differences (P > 0.05) in soil nitrate concentrations to a depth of 2.8 m were measured among the N rate treatments. Overall, substantial effects of residual N were measured in both herbage mass and steer weight gain for 3 years following 5 years of N fertilization.
Soil properties and species diversity of grazed crested wheatgrass and native rangelands
Authors: Krzic M. , Broersma K. , Thompson D. J. ,   Society for Range Management
Published: March 2016

Crested wheatgrass (Agropyron cristatum (L.) Gaertn.) is an introduced grass used extensively for rangeland revegetation in the semiarid and arid regions of western North America. The long-term effects of crested wheatgrass on soil properties and plant community were evaluated on 5 grazed sites in the southern interior of British Columbia, Canada. Each site included plant communities of native bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) Scribn. & Smith) and 14- to 60-year-old stands of crested wheatgrass. Soil samples and plant data were collected in June 1997. Species numbers were similar for native and crested wheatgrass rangelands, while the diversity index of crested wheatgrass rangeland was lower due to lower evenness. Crested wheatgrass and native grasses were observed to produce similar amounts of root biomass. Most soil properties were similar under the 2 rangelands. One of the exceptions was soil carbon at 0–7.5 and 7.5–15 cm depths, which was higher on crested wheatgrass than native rangeland. Soil nitrogen at 15–30 cm depth was also higher on crested wheatgrass rangeland. Greater soil penetration resistance was observed at 7.5 and 9 cm depths on crested wheatgrass than native rangeland. Higher soil compaction was caused by grazing of crested wheatgrass earlier in the season when soils are wetter relative to the native rangeland. The results of this study indicate that seeding of crested wheatgrass combined with the long-term grazing by cattle did not result in the degradation of soil properties, but plant diversity was reduced relative to grazed native, bluebunch wheatgrass rangeland.
Supplemental barley and charcoal increase intake of sagebrush by lambs
Authors: Banner R. E. , Rogosic J. , Burritt E. A. ,   Society for Range Management
Published: March 2016

We evaluated the influence of supplemental barley and activated charcoal on the intake of sagebrush by lambs in individual pens. In 3 experiments, lambs were fed sagebrush (harvested and chopped to 2-3 cm) during the morning; they were fed a basal diet of alfalfa pellets in the afternoon. In the first experiment, lambs supplemented with activated charcoal + barley ate more A. tridentata ssp. vaseyana than lambs supplemented with barley (304 vs. 248 g; P = .071). A second set of experiments, which consisted of 3 trials, determined the effects of activated charcoal, barley, and subspecies of sagebrush on intake of sagebrush. Lambs supplemented with activated charcoal + barley ate more A. tridentata ssp. vaseyana (Trial 1; 292 vs. 225 g; P = .086), and more A. tridentata ssp. tridentata (Trial 2; 371 vs. 255 g; P = .031) than lambs supplemented with barley. In Trial 3, lambs supplemented with barley ate more sagebrush than lambs that were not supplemented (480 vs. 318 g; P = .0002). A third set of experiments compared activated charcoal + barley, barley, and no supplement in 2 trials. In Trial 1, lambs supplemented with activated charcoal + barley or barley generally ate more A. tridentata ssp. vaseyana than lambs not supplemented (P = .017). In Trial 2, lambs supplemented with activated charcoal + barley ate slightly more A. tridentata ssp. vaseyana than lambs supplemented with barley, and they ate substantially more than lambs not supplemented (P = .032). Collectively, the results suggest that energy from supplemental barley increased intake of sagebrush by lambs fed a basal ration of alfalfa pellets which are high in protein, and that activated charcoal played a minor role in further increasing intake of sagebrush.
Comparison of 3 techniques for monitoring use of western wheatgrass
Authors: Halstead L. E. , Howery L. D. , Ruyle G. B. ,   Society for Range Management
Published: March 2016

Forage use data can help rangeland and wildlife managers make informed decisions. However, managers need to know if forage use techniques that are commonly used to estimate ungulate herbivory under field conditions produce comparable results. The objective of this 2-year study was to directly compare forage use measurements obtained via the paired-plot method and 2 height-weight methods (using on-site height-weight curves and the pre-established United States Forest Service height-weight gauge). In June, July, and October of 1997 and 1998, we measured forage use of western wheatgrass (Pascopyrum smithii Rydb.) by cattle (Bos taurus L.) and wild ungulates, mainly elk (Cervus elaphus L.). On-site height-weight curves and the USFS gauge consistently produced lower estimates (overall means = 8 and 7%, respectively) than the paired-plot method (overall mean = 31%). Height-weight estimates did not differ (P > 0.05) when calculated with either on-site curves or the USFS gauge. Within sampling areas, paired-plot estimates were relatively more precise (mean CV = 63%) than on-site curves (mean CV = 238%) or the USFS gauge (mean CV = 271%). Selective grazing likely contributed to higher CVs for height-weight techniques. Our findings are important for rangeland and wildlife managers because the forage monitoring technique they use may influence the results obtained and, consequently, grazing management and wildlife harvest decisions. Managers should ensure that chosen monitoring techniques provide an appropriate evaluation of management goals and objectives.
Short-term grazing exclusion effects on riparian small mammal communities
Authors: Giuliano William M. , Homyack Joshua D. ,   Society for Range Management
Published: March 2016

Grazing of livestock in streams and associated riparian habitats (hereafter referred to as riparian zones) may affect small mammal communities by influencing vegetation, water quality, and other site characteristics. To better understand these effects, we compared vegetation structure, and abundance and richness of small mammals in grazed riparian zones and similar areas where livestock had recently (1-2 years) been excluded in southwest Pennsylvania, 1998 and 1999. Mammalian species richness and abundance (all species combined, meadow voles [Microtus pennsylvanicus Ord], and meadow jumping mice [Zapus hudsonius Zimmermann]) were greater on sites where livestock had been excluded than grazed areas. These findings are likely the result of greater litter cover and increased vertical vegetation obstruction observed on these sites. Because small mammal communities respond quickly to relaxation of grazing in riparian zones, subsidy programs exist to partially pay for fencing, and landowners may potentially benefit from fencing these areas through improved water quality, erosion control, and livestock health, fencing may be an effective wildlife and grazing management tool.
Comparing Comparisons: Political Implications of Different Notions of Difference
Authors: Odom Glenn
Published: March 2016

With the rise of the American world literature movement, questions surrounding the politics of comparative practice have become an object of critical attention. Taking China, Japan and the West as examples, the substantially different ideas of what comparison ought to do – as exhibited in comparative literary and cultural studies in each location – point to three distinct notions of the possible interactions between a given nation and the rest of the world. These contrasting ideas can be used to reread political debates over concrete juridical matters, thereby highlighting possible resolutions. This work follows the calls of Ming Xie and David Damrosch for a contextualization of different comparative practices around the globe.
Synthesis, Characterization, and Antifungal Activity of Phenylpyrrole-Substituted Tetramic Acids Bearing Carbonates
Authors: Xu Wen-Qin , Chen Min , Wang Kun-Yao , Ren Zheng-Jiao , Lu Ai-Min , Yang Chun-Long
Published: March 2016

For the aim of discovering new fungicide, a series of phenylpyrrole-substituted tetramic acid derivatives bearing carbonates 6a–q were designed and synthesized via 4-(2,4-dioxopyrrolidin-3-ylidene)-4-(phenylamino)butanoic acids 4a–k and the cyclized products 1′,3,4,5′-tetrahydro-[2,3′-bipyrrolylidene]-2′,4′,5(1H)-triones 5a–k. The compounds were characterized using IR, 1H- and 13C-NMR spectroscopy, mass spectrometry (EI-MS), and elemental analysis. The structure of 6b was confirmed by X-ray diffraction crystallography. The title compounds 6a–q were bioassayed in vitro against the phytopathogenic fungi Fusarium graminearum, Botrytis cinerea and Rhizoctonia solani at a concentration of 100 μg/mL, respectively. Most compounds displayed good inhibitory activity.
Clean Transformation of Ethanol to Useful Chemicals. The Behavior of a Gold-Modified Silicalite Catalyst
Authors: Falletta Ermelinda , Rossi Michele , Teles Joaquim , Della Pina Cristina
Published: March 2016

Upon addition of gold to silicalite-1 pellets (a MFI-type zeolite), the vapor phase oxidation of ethanol could be addressed to acetaldehyde or acetic acid formation. By optimizing the catalyst composition and reaction conditions, the conversion of ethanol could be tuned to acetaldehyde with 97% selectivity at 71% conversion or to acetic acid with 78% selectivity at total conversion. Considering that unloaded silicalite-1 was found to catalyze the dehydration of ethanol to diethylether or ethene, a green approach for the integrated production of four important chemicals is herein presented. This is based on renewable ethanol as a reagent and a modular catalytic process.
Effects of Astaxanthin from Litopenaeus Vannamei on Carrageenan-Induced Edema and Pain Behavior in Mice
Authors: Kuedo Zulkiflee , Sangsuriyawong Anantita , Klaypradit Wanwimol , Tipmanee Varomyalin , Chonpathompikunlert Pennapa
Published: March 2016

Carrageenan produces both inflammation and pain when injected in mouse paws via enhancement of reactive oxygen species formation. We have investigated an effect of astaxanthin extracted from Litopenaeus vannamei in carrageenan-induced mice paw edema and pain. The current study demonstrates interesting effects from astaxanthin treatment in mice: an inhibition of paw edema induced in hind paw, an increase in mechanical paw withdrawal threshold and thermal paw withdrawal latency, and a reduction in the amount of myeloperoxidase enzyme and lipid peroxidation products in the paw. Furthermore the effect was comparable to indomethacin, a standard treatment for inflammation symptoms. Due to adverse effects of indomethacin on cardiovascular and gastrointestinal systems, our study suggests promising prospect of astaxanthin extract as an anti-inflammatory alternative against carrageenan-induced paw edema and pain behavior.
STRUCTURAL AND ARCHITECTURAL CHARACTERISATION OF OLD BUILDING STOCKS: CASE STUDY OF THE OLD CITY CENTRE OF SEIXAL, PORTUGAL, REBUILT AFTER THE GREAT 1755 LISBON EARTHQUAKE
Authors: Ferreira Tiago Miguel , Santos Cátia , Vicente Romeu , Silva J. A. R. Mendes Da
Published: March 2016

This paper addresses the issue of historical urban centres from the perspective of the analysis and inventory of building features. The cataloguing process of the building typologies is presented herein as a synthesis of the main construction forms, using as a case study the old city centre of Seixal, Portugal, rebuilt in its present form after the great 1755 Lisbon earthquake. As marks of an historical and architectural heritage, old urban centres should be protected, safeguarded and potentialised. Therefore, it is essential to have a complete understanding of the diachronic process of both buildings and urban mesh, in order to support qualified, conscientious and sustainable interventions.
Quality Assurance for a Developmental “Global Studies” (GS) Curriculum
Authors: Ahamer Gilbert
Published: March 2016

This chapter focuses on quality assurance (QA) for cutting-edge transdisciplinary university curricula. As a case study, it analyzes the developmental, internationally- and peace-oriented “Global Studies” (GS) curriculum at Graz University, Austria. Based on an extensive literature review on concepts of quality for curricula, key concepts for transdisciplinarity and approaches for quality monitoring are provided. This analysis finds and emphasizes that QA criteria are highly dependent on the stakeholders' perspective; notably on the perspectives of lecturers, students, university administration, and external auditors. Based on several practical sets of such stakeholder-dependent QA criteria, quality in the Graz-based GS curriculum is assessed thoroughly. Detailed recommendations for quality enhancement are provided by students, lecturers and external auditors with a focus on: transdisciplinarity; relevance to practice; maintaining existing levels of academic requirements; and especially sound, sufficient and sustained funding by the university administration.
The Impact of Information Systems on Management Performance in the Pharmaceutical Industry
Authors: Elshorbagy Sherif , Garg Lalit , Gupta Vipul , Narayanamurthy Gopalakrishnan , Al Oraini Yosuf Abd
Published: March 2016

There are many aspects that should be considered while implementing ISs in pharmaceutical companies. This is due to the various regulations and standards that the governmental authorities impose on these companies. In addition, any audit from US Food and Drug Administration (FDA) or other authorities will require computer system validation to be performed for the implemented ISs to ensure that all areas that affect the drugs lifecycle are following the required standards, and that each single process in this lifecycle is validated. Unfortunately, many pharmaceutical companies didn't recognize yet the importance of ISs to their businesses. The research presented in this paper examines the value of using an information system (IS) in pharmaceutical environment and how it can be a key component of improving the operational and process effectiveness by supporting the strategic decisions and enabling the decision-makers to take their decisions in short time. Lack of information in pharmaceutical companies is one of the reasons why these companies will not be able to compete in this competitive market because the delays in taking decisions, product lifecycle, and supply chain. Pharmaceutical companies required to follow various regulations and standards, and ISs are the tools that can be mapped to these standards and control the business operations without any obstacles. The authors conducted a comprehensive study to investigate the role of ISs in the pharmaceutical industry through a review of existing literatures relevant to the research subject and through a questionnaire survey with 54 participants working in the pharmaceutical industry in different countries in the Middle East. The survey aimed to understand the present status of ISs in pharmaceutical companies and the impact of ISs on management performance, operation improvement, end-users productivity, and compliance with the regulations and standards of the pharmaceutical industry in their companies. Moreover, the survey also aimed to identify the catalysts behind successful implementation of ISs.
Structure of LaNi3.8AlMn0.2 Compounds Studied by Neutron Powder Diffraction
Authors: Han Wen Ze , Guo Hao , Sun Kai , Chen De Min , Liu Shi , Wu Er Dong , Liu Yun Tao , Chen Dong Feng
Published: March 2016

The structures of as-cast LaNi3.8AlMn0.2 alloys and subsequent compounds by means of annealing at different temperature (850, 900, 950, 1000 oC) were examined by using neutron powder diffraction (NPD) and X-ray diffraction (XRD). Based on the Rietveld method, the diffraction data was refined using FullProf software. The refined results demonstrate the structure types of all compounds are CaCu5 type and their space groups are P6/mmm. Increasing the annealing temperature, the lattice parameters of LaNi3.8AlMn0.2 compounds did not possess clearly linear variation. It is noted that Mn atoms do not occupy the 2c sites but occupy the 3g sites in all compounds.
Analysis on Influence Factors of Greenhouse Gas Emissions of Magnesium Production Process
Authors: Cao Yan Cui , Gao Feng , Wang Zhi Hong , Gong Xian Zheng , Li Xiao Qing
Published: March 2016

Magnesium is a promising lightweight and green metallic engineering material, but the environmental impact of primary magnesium production stage, especially greenhouse gas (GHG) emissions cannot be ignored. In this study, the life cycle energy consumption and GHG emissions caused by the production of primary magnesium in the years of 2003-2013 in China were calculated; the factor decomposition was conducted to analyze the GHG emissions of magnesium production process by using logarithmic mean Divisia index method (LMDI), including energy GHG emission factors, energy structure, energy consumption per ton of primary magnesium, production, emissions per unit of dolomite and ferrosilicon, and dolomite and ferrosilicon consumptions per ton of primary magnesium. The results showed that GHG emissions of primary magnesium production increased 260.29*104 t CO2eq in total from 2003 to 2013. The variety magnesium production contributed the biggest part of GHG emissions, accounting for 418.17%. The energy structure took second place on the contribution of GHG emissions, accounting for-161.49%. The nest part was energy consumption per ton of primary magnesium, accounting for-138.97%. While, the contribution of energy GHG emission factors, emissions per unit of dolomite and ferrosilicon, and dolomite and ferrosilicon consumptions per ton of primary magnesium was relatively small, which were 0.88%, 0.00% -2.72% -4.73% and-11.13%, respectively. Thus, it is the key methods to reduce GHG emissions by optimizing the energy structure and decreasing the energy consumption.
Research on Life Cycle Assessment of Plastic Pipeline System
Authors: Zhao Chun Zhi , Huang Meng Chi , Liu Yi , Ma Li Ping
Published: March 2016

Plastic pipe is a kind of new pipeline material and its output has been increasing in recent years. It is still mainly used for water supply and drainage of buildings and municipal utility industry as well as for safe drinking in rural areas, about half of all plastic pipelines are used for buildings, and the proportion of these pipelines used in other fields is also increasing. Plastic pipeline system's influence on the environment within its life cycle is the focus of researches in recent years. Based on life cycle assessment (LCA), this paper assesses the common water supply and drainage pipelines (PPR, PE and PVC-U) for buildings for resource and energy consumption, non-renewable resource consumption (ADP) of pollution gas emission, greenhouse effect (GWP), acidification effect (AP) and eutrophication (EP) and inhalable inorganics (RI) generated in the process of life cycle from raw material exploitation to produce production and other environmental influence closely related to the national energy conservation and emission reduction policy. The result shows that the influence indexes of non-renewable resource consumption for functional unit of PPR pipe, PE pipe and PVC-U pipe are 2.22×10-5 Kg antimony eq./ kg, 1.51×10-5 Kg antimony eq./ kg, 6.82×10-6 Kg antimony eq./ kg; those of acidification effect are 1.92×10-2kg SO2 eq./ kg, 1.96×10-2g SO2 eq./ kg, 3.90×10-2kg SO2 eq./ kg; those of eutrophication are 2.39×10-3kg PO43-eq./ kg, 2.36×10-3kg PO43-eq./ kg, 3.40×10-3kg PO43-eq./ kg; those of inhalable inorganics are 6.46×10-3 kg PM2.5 eq./ kg, 6.30×10-3 kg PM2.5 eq./ kg, 1.91×10-2 kg PM2.5 eq./ kg; those of greenhouse effect are 3.72kg CO2 eq./ kg, 3.60kg CO2 eq./ kg, 7.93kg CO2 eq./ kg. This result shows that the environmental influence of PPR, PE and PVC-U pipes mainly depends on the raw materials required for producing pipes, so the key of plastic pipeline greening is to reduce the consumption of virgin resin. This investigation creates a database about plastic pipeline's influence on environment within its full life cycle for the purpose of laying a foundation for calculating intrinsic energy in a building, promoting selection of green building material, facilitating the realization of green building objective, and improving the knowledge of developer, constructor and user to potential influence of the pipeline system within its life cycle.
Research on Produced Fluid Corrosion Resistance Oil Well Cement Paste System in Adjustment Well
Authors: Zhang Jing Fu , Chen Jun Dong , Wang Yu , Lv Ying Bo
Published: March 2016

To design oil well cement paste system and ensure well cementation quality of adjustment well in work area of tertiary oil recovery (EOR), the composition, microstructure and strength of cement paste matrix eroded by producing water were tested and studied by HTHP Curing Chamber, HTHP corrosion tester, X-ray diffraction, scanning electron microscope (SEM), universal testing compressor and some other laboratory equipment according to the condition that producing water contains sulfate (SO42-) and bicarbonate (HCO3-). The corrosion law and mechanism of oil well cement paste matrix were analyzed. The problem for designing corrosion resistance oil well cement paste system was investigated. The corrosion law and mechanism of oil well cement paste matrix by SO42- and HCO3- were raised. The corrosion resistant oil well cement paste system was designed, which was suitable to the adjustment well in area of EOR in Daqing. The results show that the compositions of cement paste matrix changed after corrosion by SO42- and HCO3- for a long term. The secondary gypsum, ettringite and calcite were produced, which changed the microstructures and declined the compressive strength of cement paste matrix. The change degree of compressive strength of cement paste matrix was affected by corrosion media concentration, corrosion time and other conditions. The higher concentration of corrosion media and the longer of corrosion time were, the greater decline of cement strength occurred. The formula of corrosion resistance oil well cement paste system was designed, for which the high sulfate resistant cement as architectural substrate and the PZW as admixtures were used to improve the strength and penetration resistance ability of cement.
Study on Sorption Behavior of Cesium by Graphite
Authors: Wang Wei Jun , Chen Bo , Zheng Jian Ping , Lei Hua Zhen , Qi Li Jun , Zhao Jun
Published: March 2016

It has long been recognized that a need for practical methods for maintaining optimum cesium pressure within a thermionic energy converter has been pursued for space applications. An attractive solution to the problem is the use of a sorption type reservoir where cesium absorbed into a lattice. Four graphite materials were initially investigated for the potential usage as cesium storage media. Primary research focusing on the characteristics of loading ability, structural integrity, and dimensional change of these materials was performed by synthesizing proper cesium-graphite lamellar compounds with a two zone vapor transport method. Graphite foams show promising prospect for thermionic application as integral cesium reservoir material.
Research on a Coated Method for Ceramic Proppant
Authors: Zhu Zi Yu , Xiang Ke Lan , Zhao Ying Zi , Li Lin , Wang Xu
Published: March 2016

Due to the disadvantage of the traditional proppant, such as the low strength, poor acid corrosion resistance, embedding and flowback and so on, a new coated proppant was developed to deal with these problems. As the coating material, the natural gel was used to coat proppant. Different from the traditional mechanical mixing method, the means to make coated ceramic was the solvent dispersion method through the process of emulsification, cross-linking and dehydration dispersion. The strength of coated proppant was tested in different coated conditions. According to the result of test, the ceramic was coated under the optimum condition. Then the roundness, sphericity, acid solubility, crush resistance and surface structure of coated ceramic were compared with the uncoated ceramic. The experimental results showed that the optimal condition was as follows: 0.08 g/ml of gel concentration, 15/2 of ceramic/gel (g/g), 0.025 g/ml of emulsifier concentration, 20min of emulsifying time, 1/10 of water/oil rate. The coated ceramic prepared at this condition had the best performance, compared with the common ceramic, and its sphericity and acid solubility were greatly improved, bulk density reduced 7%. And the proppant surface was very smooth, the crush resistance was almost zero.
Study on Nonionic Surfactant Gel Fracturing Fluid
Authors: Zhao Ying Zi , Zhu Zi Yu , Zhong Zhi Gang , Guo He Yun , Wang Xu
Published: March 2016

Two kinds of nonionic surfactants were synthesized to configure fracturing fluid that can make up for the inadequacy of cationic surface active agent which has damage to the formation. The effect of the surfactant concentration on the apparent viscosity was discussed in this paper. The shear resistance, heat resistant, sand-carrying performance and gel breaking of the fracturing fluid were evaluated as well. It was shown that 2% of the surface active agent which was synthesized by oleic acid could crosslink in aqueous solution with the help of cosurfactant, and the viscosity could remain in 40mPa·s at 60°C, 170s-1; 3% of the surface active agent which was synthesized by erucic acid could crosslink in aqueous solution with the help of cosurfactant, and the viscosity could remain in 45mPa·s at 90°C, 170s-1. The elastic modulus G'≥2 and viscous modulus G"≥0.3 at 25°C and 0.01~10Hz frequency range showed that the fracturing fluid had good viscoelasticity. In the condition of 30°C, 70°C, sand sedimentation rates were 0.02 mm/s, 0.57 mm/s and 0.04 mm/s, 0.72 mm/s, meaning that the carrying capacity was perfect. The systems could be broken with kerosene, the gel breaking liquid was clarified and had no residue. So the fracturing fluids were suitable for the low and medium-high temperature formation.
Preparation and Characterization of Multiwalled Carbon Nanotubes-Reinforced pCBT by Ring-Opening Polymerization of Cyclic Butylene Terephthalate
Authors: Su Yin He , Yu Jun Rong
Published: March 2016

Multiwalled carbon nanotubes (MWCNT)-reinforced polymerized cyclic butylene terephthalate (pCBT) nanocomposites were prepared by in situ ring opening polymerization of cyclic butylene terephthalate oligomers (CBT). The results of differential scanning calorimetry (DSC) indicated that the melting peak located at the low temperature (Tm1) increased and that at higher temperature (Tm2) decreased with the increasing of content of the MWCNT. During the cooling the MWCNT served as nucleation points from where crystallization can start. The more the MWCNT in the system the earlier the crystallization starts. The Morphological investigations performed by scanning electron microscopy (SEM) shown that the MWCNT were embedded in the matrix and held tightly by the matrix. The modulus and strength increased with MWCNT concentration in the nanocomposites, however, the elongation at break, absorbed energy at break and impact strength were decreased with the increasing of MWCNT content.
Progress in Conductive-Polymer Carbon Nanotube Composites
Authors: Xu Run Run , Wu Xiang Hong , Han Yun Long
Published: March 2016

Carbon nanotube (CNT) has been widely used as a kind of conductive inorganic filler in composites due to its excellent mechanical properties, thermal properties and electrical properties. Unfortunately, a deal of CNT is needed because it tends to agglomerate in matrix polymers. And therefore the researchers need to explore appropriate methods to decrease the usage of CNT for its high price. This paper summaries the recent development progress in carbon nanotube filled conductive polymer composites, in aspects of the approaches how to reduce the usage of CNT and application of biodegradable CNT-polymer composites. In addition, the future developing research direction in conductive polymer composites filled with carbon nanotube was indicated.
Preparation and Properties of Polyurethane Films with Spent Coffee Grounds
Authors: Li Rui Xue , Shen Xiao Lin , Zhou Yi , Wang Hao , Jiang Shan , Xu Wei Lin
Published: March 2016

In this study, a method of recycling spent coffee grounds (SCG) is introduced. The SCG was dried and crushed into micron-sized coffee particles. The coffee particles could be used to prepared polyurethane (PU) films with different contents (0wt.%, 5wt.%, 10wt.%, 15wt.%, 20wt.%, 25wt.% and 30wt.%). The anti-ultraviolet property, thermal comfort performance and mechanical property of different PU films were measured. The results showed that after the blending of coffee particles, the films exhibited excellent anti-ultraviolet property and thermal comfort performance, and the mechanical properties were also retained. This study also provided an effective approach to reuse SCG, which is consistent with the environmental-friendly society principle.
Variation of Transparency of Zeolite-Derived Silica Glass Prepared by Spark Plasma Sintering
Authors: Gu Shi Jia , Wang Lian Jun , Jiang Wan , Luo Wei
Published: March 2016

A series of zeolite-derived silica glasses have been fabricated through the order-disorder transition process of zeolites using spark plasma sintering (SPS). The samples were characterized by UV-VIS-NIR transmittance, Raman spectra and Vicker’s hardness. Results showed that the transmittance of zeolite-derived silica glass samples increased with the sintering temperature increasing. The transmittance of the sample prepared at 1300°C was lower than 5%. The highly transparent samples could be obtained when the sintering temperature was above 1350°C. The transmittance of these samples was higher than 80% in the range of 780~1700nm and 60% in the UV-vis range of 250~780nm. One absorption band at 300nm can also be observed in the spectrum. The reason of this phenomenon could be ascribed to a few left crystallite fragments of ZSM-5. The Raman spectra showed that the bands at 378 and 292cm-1of ZSM-5 were significantly weakened and then disappeared with increasing the sintering temperature and the bands at 489 and 600cm-1 of silica glass became more apparent. The Raman spectra of the samples obtained above 1350°C were the same as that of the fused silica glass. The Vicker’s hardness of as-prepared samples increased with the rising of the sintering temperature. The maximum hardness of 7.31 GPa was achieved for the sample sintered at 1400°C. The fracture toughness of samples increased from 0.83 MPa·m1/2 to 2.37 MPa·m1/2 with the sintering temperature increasing.
The Design of a Wideband Microwave Absorber Based on Resistively Single Square-Loop Arrays
Authors: Song Xiang Lian , Song Li Xin , Zhang Tao
Published: March 2016

A non-magnetic microwave absorber was proposed, for which the-10dB absorbing bandwidth would operate over all the X-band with a total thickness of 4 mm. The designed structure was composed by resistively single square-loop FSS on the surface of metal-backed dielectric substrate. The influence of the substrate and FSS was discussed for absorption optimization. Besides, the current distribution of the FSS was investigated to explain the principle of resonance. Good accordance of the experimental results and the simulated results has been achieved, indicating the feasibility of our designed structure and the reliability of the simulated method.
Replacement of High-Purity Copper Target by High-Purity Copper Alloy Target in Very Large Scale Integrated Circuit
Authors: Gao Yan , Liu Xiu , He Jin Jiang , Zeng Hao , Xiong Xiao Dong , Wang Yue
Published: March 2016

With the development of semiconductor technology, the size of complementary metal oxide semiconductor (CMOS) devices has been scaled down to nanoscale dimensions. The technology of copper interconnection is the mainstream technology, so the request of the copper target is more and more rigor. This article analyzes the impact factors on the copper alloy target capability, including oxidation and strength. The aim of this investigation is to set up a bridge between the vendors of copper targets and the foundries of integrated circuit (IC) chip, and the base for the next generation copper targets.
Synthesis of Highly Luminescent CdSe/ZnCdS Quantum Dots with Deep-Red Emissions
Authors: Tan Jing , Guo Jian Quan , Wu Wei Na , Shi Qian , Li Wei , Li Chun Liang
Published: March 2016

CdSe cores with larger radius were prepared by means of two-steps injection of the Cd precursor. Efforts were made to avoid the Ostwald ripening process during the quantum dots grown up. The prepared CdSe cores showed zinc-blende structure with size exceeded over 7 nm. The emission efficiency of prepared quantum dots were 15%, while it increased drastically up to 43% after the formation of ZnCdS shells on the CdSe cores. Morphologies and structures of the quantum dots were characterized by HR-TEM and XRD diffraction. The obtained quantum dots with emission wavelengths more than 660 nm were expected to find their applications in bio-imaging and plant illuminations.
Synthesis of Silicon Microspheres
Authors: Liu Lian Yun , Zhang Ting Ting , Zhang Hui , Bai Xia Xia , Polizzi Stefano
Published: March 2016

The synthesis of silicon microspheres is of outmost importance, especially for the production of optical and electrical devices due to their unique properties displayed by this material. In this paper, we review the research on the synthesis of silicon microspheres, including one physical method, the drop method and several chemical methods, such as vapor-phase reaction, vapor-solid reaction, liquid phase reaction and magnesio-thermal reduction method. The formation mechanisms for silicon microsphere particles are also summarized.
Structure, Magnetostriction and Magnetic Properties of the Mn100-xFex (x=50, 58) Alloys Prepared by SPS
Authors: Zhou Liang , Ma Lei , Zhao Shi Qian , Cheng Lin Yi , Du Yu Song
Published: March 2016

Mn100-xFex (x=50, 58) alloys were prepared by spark plasma sintering (SPS), and the structure, magnetostriction and magnetic properties of the polycrystalline Mn100-xFex alloys were investigated. The results of XRD and SEM showed that the as-cast and annealed samples presented a single face center cubic γ-phase, which is austenite structure. The magnetic measurement showed that Mn100-xFex (x=50, 58) alloys annealed at 700oC were a typical ferromagnet at low temperature and there was a gradual transition from the ferromagnetic phase to the paramagnetic phase in a wide temperature region (about 150-250K). The magnetostriction for the annealed samples, measured by strain-gauge bridge up to 3T, was ~100 ppm at 300K, but the results was chaotic. The results are not in agreement with the results reported. The further research on the mechanism of the magnetostriction is needed.
Lateral Inhomogeneity of Critical Current of HTS Conductor Using Hall Sensor Array
Authors: Zhu Yun Peng , Yang Xin Sheng , Zhao Yong
Published: March 2016

A reel-to-reel Hall sensor array system was build and an inverse operation algorithm was applied to obtain the lateral distribution of critical current density by the remanent field around the superconducting tape. Simulation analysis was conducted to verify the validity of the algorithm. Commercial YBCO and Bi2223 tape and YBCO tape with artificial defects were measured. The standard deviation of lateral critical current density on the cross section of conductor was used as a parameter describing the lateral inhomogeneity of critical current density. The result shows that this measurement method is a stable and efficient way to evaluate the lateral inhomogeneity of critical current of high temperature tapes.
Photocatalytic Property of Rice Husk Char/TiO2 Composite Prepared by Low-Temperature Method
Authors: Cheng Xu , Li Yue Ming , Wang Biao , Jiang Jian Ming
Published: March 2016

In this paper, low-temperature preparation of rice husk char/TiO2 composite was developed by utilizing agriculture waste. nanosized TiO2 particles were successfully loaded to rice husk char by in-situ thermal treatment of impregnated rice husk. The structural characteristics and photocatalytic activities of obtained composites were investigated. The specific surface area of rice husk char was enlarged due to the catalytic effect of loaded TiO2 during thermal treatment. The porous rice husk char matrix combined with nanosized TiO2 particles offered large specific surface area and good photocatalytic property. This low-temperature preparation method provided a promising way to reuse the waste biomass and extended the applications of charcoal.
Preparation and Properties of Recycled PET Fibers Filled Polyethylene Composites
Authors: Wang Zhi Gang , Xi Wen Hao , Zhou Jing Bo , Xu Jia Ming , Li Guang
Published: March 2016

Responding to the resource waste and environmental damage, the recycled Polyethylene Terephthalate (PET) fibers were successfully obtained from waste PET textiles using a PFI mill. The high density polyethylene (HDPE)-based composites reinforced with recycled PET fibers were manufactured by melting blend. The mechanical properties of the composites were investigated by mechanical property test. The thermal stability and crystallinity were analyzed by Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), and their microstructures were characterized by Scanning Electron Microscopy (SEM). The mechanical properties of the composites indicated the significant improvements in tensile, flexural and impact properties by increasing the recycled PET fibers to 20wt%. The morphological and structural results showed that the recycled PET fibers dispersed well in HDPE matrix with the help of PE-g-MAH as a compatibilizer. The thermal analysis revealed that the degree of crystallinity and crystallizing rate tended to increase, while the thermal stability remained stable. In addition, using PFI mill in dealing with the waste textiles will help open new ways for recycling of waste textiles.
Polydopamine Nanoparticle for Poly(N-Isopropylacrylamide)-Based Nanocomposite Hydrogel with Good Free-Radical-Scavenging Property
Authors: Xiong Shu Qiang , Wang Yan , Zhu Jing , Hu Zu Ming , Yu Jun Rong
Published: March 2016

Nanocomposite hydrogels (NC gels) consisting of poly (N-Isopropyl acrylamide) (pNIPAM)/polydopamine nanoparticles (PDAPs) were prepared by in-situ-free-radical polymerization of N-isopropyl acrylamide in the presence of modified PDAP in aqueous solution. The composition of the NC gels could be controlled directly by altering the composition of the initial reaction mixture. The lower critical solution temperature (LCST) of the NC gels were studied by DSC, and the LCST of both of pure pNIPAM hydrogel and NC gels was at 34°C. Besides, the NC gels showed superior antioxidant property, and the ability to scavenge activity of NC gel was up to 70% with the addition of 6 wt% modified PDAP into pNIPAM.
Evolution of Microstructure and Mechanical Properties of ZK80 Mg Alloy during Net-Shape Pressing of Extruded Perform
Authors: Cao Feng Hong , Chen Yun Gui , Long Si Yuan
Published: March 2016

The microstructure and mechanical properties of as-cast ZK80 Mg alloy during net-shape forming of tensile specimens with close-die pressing extrusion, and the effect of extrusion-forging on the fracture mechanism of ZK80 alloys were studied in the present investigation. The results indicated that Rm (σb)、Re (σs) and A(δ) of compound forming ZK80 Mg alloy had noticeable improvement. Large deformation and produce twins, lead to grain refinement and had strongly influence on mechanical property of ZK80 Mg alloy, as well as strong affected the mechanical properties of the alloy. It was found that as-cast ZK80 Mg alloy has mixed fracture characteristics including cleavage fracture, intergranular facture and ductile fracture. As-extruded perform and as-close die ZK80 Mg alloys were obvious dimples for ductile fracture pore nucleation mechanism.
Preparation and Characterization of As-Cast and As-Extruded Mg-1Mn-0.6Ce-3Y Alloy
Authors: Su Gui Hua , Liu Xue Ran , Cao Zhan Yi
Published: March 2016

Mg-1Mn-0.6Ce-3Y alloy was prepared by metal mould casting method. The as-cast ingot was homogenized and then hot-extruded by an extrusion ratio of 16:1 at 380 °C. Microstructure and mechanical properties of the as-cast and hot-extruded samples were investigated. The results showed that the as-cast sample mainly consisted of α-Mg, Mg12Ce, and Mg24Y5 phases. The average grain size of the sample homogenized at 380 °C was about 100μm, and it was greatly refined to about 6μm by dynamic recrystallization for the hot-extruded sample. The ultimate tensile strength, 0.2% yield strength and elongation of the hot-extruded sample were 244 MPa, 178 MPa and 37.5%, respectively. They were enhanced by 82%, 197% and 400%, correspondingly compared with those of the as-cast sample. The improvement of the strengths was attributed to the grain refinement, breakup of the precipitates and increase of the dislocation density.
Influence of Upsetting and Drawing Times on the Microstructure and Microtexture of TC4 Titanium Alloy
Authors: Yan Meng Qi , Li Kai , Wang Yu Hui , Zhang Wang Feng
Published: March 2016

TC4 titanium alloys have been extensively used in the aerospace engineering due to the high specific strength, high temperature resistance and good corrosion resistance. However, unsuitable forging methods will cause unqualified mechanical properties in the height direction of forgings. The microstructure and microtexture of the forgings after two forging processes with different upsetting and drawing times were investigated by optical microscopy (OM) and electron back scattering diffraction (EBSD) technique. The results showed that bimodal microstructure and weak basal {0002} texture can be obtained after forging. With the increase of upsetting and drawing times, lamellar α were curved and coarsen, basal {0002} texture were enhanced, and the special 60°<11-20> preferred orientation between lamellar α phase due to Burgers relationship was avoided. The modification of microtexture and grain boundary distributions can improve the strength of TC4 titanium alloy forging in the height direction.