scholarly journals The depositional evolution, reservoir characteristics, and controlling factors of microbial carbonates of Dengying Formation in upper Neoprotozoic, Sichuan Basin, Southwest China

2017 ◽  
Vol 36 (4) ◽  
pp. 591-619
Author(s):  
Jinmin Song ◽  
Shugen Liu ◽  
Hairuo Qing ◽  
Luba Jansa ◽  
Zhiwu Li ◽  
...  
Keyword(s):  
Fresh Water ◽  
Sichuan Basin ◽  
Depositional Environments ◽  
Microbial Carbonates ◽  
One Stage ◽  
Dengying Formation ◽  
Microbial Carbonate ◽  
Three Stages ◽  
Two Stages ◽  
Water Dissolution

The Dengying Formation of Neoprotozoic age deposited in north Sichuan Basin, China, is dominated by dolomitic strata containing microbial carbonates. Thirteen cyanobacteria forms, one oncolite and two stromatolitic structures have been identified. Different microfacies may be related to different microbe forms or assemblages as well as depositional environments. Potential hydrocarbon reservoirs in microbial carbonates are of low porosity and permeability. Microbialites develop in the members Z2 dn1, Z2 dn2, and Z2 dn4. The member Z2 dn1 and Z2 dn2 lying in the lower part, dominated by thrombolitic and spongiostromata dolostone, with three reservoir intervals of overall 190 m thick. Laminite and stromatolitic dolostone are the most important in member Z2 dn4, with three reservoir intervals of 119 m thick. Microbial carbonate reservoirs in members Z2 dn1 and Z2 dn2 were effected by two stages of fresh water dissolution, three stages of burial dissolution, and one stage of hydrocarbon invasion. But one stage of fresh water dissolution, two stages of burial dissolution, and three stages of hydrocarbon invasion modified the reservoirs of member Z2 dn4. The dominant factors for microbial reservoirs were microbial textures and development of Mianyang-Changning intracratonic sag.

scholarly journals Sedimentary and Diagenetic Features and Their Impacts on Microbial Carbonate Reservoirs in the Fourth Member of the Middle Triassic Leikoupo Formation, Western Sichuan Basin, China

Energies ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2293
Author(s):  
Yuanchong Wang ◽  
Weimin Jiang ◽  
Hangyu Liu ◽  
Bo Liu ◽  
Haofu Zheng ◽  
...  
Keyword(s):  
Sichuan Basin ◽  
Depositional Environments ◽  
Sw China ◽  
Western Sichuan ◽  
Microbial Carbonates ◽  
Rock Types ◽  
Multi Stage ◽  
Leikoupo Formation ◽  
Western Sichuan Basin ◽  
Fourth Member

In recent years, the discovery of two gas fields in the fourth member of the Leikoupo Formation in the Western Sichuan Basin of SW China confirmed the exploration potential of microbial carbonates. The aim of the present study is to clarify the formation mechanism of the microbial reservoirs in the Leikoupo Formation. For this purpose, lithofacies, depositional environments, and diagenesis analyses were performed in samples collected from cores of 12 wells. The climate of study area was arid during Anisian time, and the water body was restricted. In such a climate, an evaporitic environment was developed, where ten types of lithofacies, dominated by microbial carbonates and gypsum rocks, were recognized. Thrombolites and stromatolites are the main high-quality reservoirs rock types in the fourth member of the Leikoupo Formation in the Western Sichuan Basin of SW China, which developed as microbial mounds, with reservoir space of microbial inter-clot pores, intra-clot pores, fenestral pores, inter-crystalline pores, and cracks. The microbial inter-clot pores are the main reservoir space, formed by trapping and binding of marls by benthic microbial communities. These pores were partially filled with evaporites because of the arid climate, which were subsequently dissolved (mainly gypsum) in the syn-depositional period, thus greatly improving the quality of reservoirs. Although some pores were occluded by multi-stage cements during the burial stage, major pores were well preserved own to the early dolomitization, rapid burial of the Leikoupo Formation, and early charging of hydrocarbon. The early dolomitization enhanced the anti-compaction ability of microbial carbonates during the burial stage. Rapid burial of the Leikoupo succession slowed down early cementation, and it also accelerated the maturation and expulsion process source rock to promote early charging of hydrocarbon in pores, which created a closed system, inhibiting strong burial cementation.

A Simulation Study of FIR Anti-Aliasing Filters

2014 ◽  
Vol 687-691 ◽  
pp. 4029-4032
Author(s):  
Yi Huai Yang ◽  
Li Fang Wang ◽  
Yuan Li
Keyword(s):  
Computational Complexity ◽  
Simulation Study ◽  
Fir Filters ◽  
Linear Phase ◽  
Design Scheme ◽  
One Stage ◽  
Three Stages ◽  
Simulation Results ◽  
Two Stages

This paper brief describes FIR anti-aliasing filters with equiripple pass bands and stop bands. We designed equiripple linear-phase FIR filters with one stage, two stages and three stages. The simulation results of the proposed design scheme are very encouraging as far as robustness and computational complexity are concerned

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

Study on Drying Characteristics of Microalgae under Different Conditions

2013 ◽  
Vol 724-725 ◽  
pp. 296-299
Author(s):  
Chun Xiang Chen ◽  
Xiao Qian Ma ◽  
Xiao Cong Li ◽  
Wei Ping Qin
Keyword(s):  
Moisture Content ◽  
Mass Loss ◽  
Fresh Water ◽  
Chlorella Vulgaris ◽  
Drying Process ◽  
Drying Time ◽  
Drying Characteristics ◽  
Second Stage ◽  
Drying System ◽  
Two Stages

To find out an alternative of coal saving, a kind of microalgae, Chlorella vulgaris (C. vulgaris) which is widespread in fresh water was studied by digital blast drying system. The effect of the moisture content, drying thickness and temperature on the drying process of C. vulgaris were investigated. The results indicated that when the drying temperature is high, the moisture content is low and the material thickness is small, the drying time is short. The drying process of C.vulgaris can be divided into two stages, and the mass loss is mainly occurred in the second stage . The results will provide guidance for design of drying process and dryer of microalgae.

scholarly journals Subtalar Joint Arthritis After Total Ankle Replacement

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0011
Author(s):  
Marc Sokolowski ◽  
Lukas Zwicky ◽  
Christine Schweizer ◽  
Beat Hintermann
Keyword(s):  
Subtalar Joint ◽  
Total Ankle Replacement ◽  
Consecutive Series ◽  
Secondary Degeneration ◽  
One Stage ◽  
Joint Fusion ◽  
Subtalar Fusion ◽  
Ankle Replacement ◽  
Two Stages

Category: Ankle Arthritis Introduction/Purpose: It has been shown that total ankle replacement (TAR) is effective in reducing pain and maintaining function in posttraumatic ankle osteoarthritis (OA). Compared to ankle fusion, TAR restores hindfoot kinematics more physiological. However, the assumption that the maintenance of ankle motion has a protective effect on the subtalar joint is still a matter of debate. Only a scarce number of long-term studies exist to support this statement.The purpose of this study was (1) to evaluate to which extent the integrity of the subtalar joint can be preserved by treating patients with a TAR, (2) to determine the rate of subtalar fusion following TAR, and (3) to determine whether the need of subsequent subtalar fusion was predictable at time of TAR. Methods: A consecutive series of 1140 primary TAR (508 female, 632 male, median age 63.5 years), performed between May 2000 and December 2015, were prospectively documented. The indication for TAR was posttraumatic OA in 78%, primary and systemic OA in 10% each, and other secondary OA in 3% of the cases. 199 subtalar joints were either fused before (n=73) or during TAR surgery (n=126), leaving 941 subtalar joints available for analysis. Radiographs before implantation and at latest follow-up were classified using the Kellgren and Lawrence Grading Score (KLS). In case of a subtalar fusion, the radiograph prior to the fusion was classified. Results: After a median radiographic follow-up of 6.1 years, the KLS remained unchanged in 66% of all cases. While it was increased by one stage in 30%, it was increased by two stages in 3%; whereas, signs of OA decreased by one stage in 1%. Cases with an increase of two stages on the KLS had a longer follow-up compared to cases without increase (p=0.047).37 cases (3.9%) underwent a subtalar joint fusion, of which the indication was progressive OA in 19 cases (51%), instability in 10 cases (27%) and others in 8 cases (22%). Subtalar joints that required a fusion after TAR did not show higher preoperative KLS than the group which did not need a subtalar joint fusion. Conclusion: Apparently, TAR protects the subtalar joint from secondary degeneration, as found in 67% with no increase in KLS. Although 33% showed an increase in the KLS, only 2% required a subtalar fusion due to progressive OA. Overall, the rate of subtalar joint fusion after TAR was low and comparable to the rates reported in the literature. Subtalar joints requiring fusion after TAR did not show higher preoperative rates of OA. Therefore, the KLS classification of subtalar OA on conventional radiographs provides only limited information about the need for postoperative subtalar fusion, and thus need to be interpreted with caution.

Agent-based economic models and econometrics

2012 ◽  
Vol 27 (2) ◽  
pp. 187-219 ◽  
Author(s):  
Shu-Heng Chen ◽  
Chia-Ling Chang ◽  
Ye-Rong Du
Keyword(s):  
Financial Markets ◽  
Agent Based Modeling ◽  
Computational Finance ◽  
Agent Based ◽  
Second Stage ◽  
The Past ◽  
Stage Development ◽  
Three Stages ◽  
The One ◽  
Two Stages

AbstractThis paper reviews the development of agent-based (computational) economics (ACE) from an econometrics viewpoint. The review comprises three stages, characterizing the past, the present, and the future of this development. The first two stages can be interpreted as an attempt to build the econometric foundation of ACE, and, through that, enrich its empirical content. The second stage may then invoke a reverse reflection on the possible agent-based foundation of econometrics. While ACE modeling has been applied to different branches of economics, the one, and probably the only one, which is able to provide evidence of this three-stage development is finance or financial economics. We will, therefore, focus our review only on the literature of agent-based computational finance, or, more specifically, the agent-based modeling of financial markets.

Staging of Dietary Patterns among African American Women

1999 ◽  
Vol 26 (1) ◽  
pp. 90-102 ◽  
Author(s):  
Debra Haire-Joshu ◽  
Wendy F. Auslander ◽  
Cheryl A. Houston ◽  
James H. Williams
Keyword(s):  
African American ◽  
African American Women ◽  
Dietary Patterns ◽  
Lower Percentage ◽  
Low Fat ◽  
Community Based ◽  
American Women ◽  
Fried Foods ◽  
Three Stages ◽  
Two Stages

This article describes the development of a behavioral staging algorithm for use in the Eat Well, Live Well Nutrition Program, a peer-delivered community-based program for African American women ( N = 301). The authors examined whether increased frequency in performing low-fat eating behaviors and lower percentage calories from fat intake resulted as a participant moved through five stages of readiness to change each of five low-fat dietary patterns. Frequency of performing low-fat dietary behaviors was significantly different ( p < .05) between four stages for the pattern of avoid fried foods, three stages for modify meats, and two stages for the patterns of substitution, avoid fat as seasoning, replacement. Percentage calories from fat were significantly different ( p < .05) between four stages for the pattern of replacement, three stages for avoid fried foods and modify meats, and two stages for substitution and avoid fat as seasoning. Implications of these findings for the tailoring of community-based dietary programs are presented.

scholarly journals Construction of isotherms in solvent extraction of copper

2009 ◽  
Vol 63 (4) ◽  
pp. 309-312 ◽  
Author(s):  
Vladimir Cvetkovski ◽  
Vesna Conic ◽  
Milovan Vukovic ◽  
Goran Stojanovski ◽  
Milena Cvetkovska
Keyword(s):  
Solvent Extraction ◽  
Organic Solvent ◽  
Electrolyte Solution ◽  
Mine Water ◽  
Copper Recovery ◽  
Equilibrium Isotherms ◽  
Technological Parameters ◽  
One Stage ◽  
Two Stages

The aim of this work is construction of equilibrium isotherms in solvent extraction. Technological parameters have been predicted for treatment of mine water by solvent extraction and electrowining. Two stages of extractions and one stage of stripping have been predicted for copper recovery by analyzing the equilibrium isotherms. The process was performed on mine water with 2,5 g/dm3 Cu2+, 3 g/dm Fe2+, pH 1,8, using 9 vol% LIX 984N in kerosene (organic solvent), with 95 and 98% stages efficiencies, respectively. This course produced an advanced electrolyte solution, suitable for electrowining and cathodic copper recovery, containing 51 g/dm3 Cu2+ and 160g/dm3 H2SO4 from a 30 g/dm3 Cu and 190 g/dm3 H2SO4.

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