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Evaluation of the Performance of Lithium-Ion Accumulators for Photovoltaic Energy Storage
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作者 Toussaint Tilado Guingane Dominique Bonkoungou +4 位作者 Eric Korsaga Dieudonné Simpore Soumaila Ouedraogo Zacharie Koalaga François Zougmore 《Energy and Power Engineering》 2023年第12期517-526,共10页
In a context of climate change exacerbated by the increasing scarcity of fossil fuels, renewable energies, in particular photovoltaic solar energy, offer a promising alternative. Solar energy is non-polluting, globall... In a context of climate change exacerbated by the increasing scarcity of fossil fuels, renewable energies, in particular photovoltaic solar energy, offer a promising alternative. Solar energy is non-polluting, globally available and the most widely distributed resource on Earth. However, the intermittency of this energy source considerably limits its expansion. To solve this problem, storage techniques are being used, in particular, electrochemical storage using lithium-ion batteries. In this article, we will evaluate the performance of lithium-ion batteries when integrated into a photovoltaic grid. To do this, modelling and simulation of a photovoltaic system connected to a lithium-ion battery storage system will be carried out using MATLAB/Simulink software. A diagnostic of the energy consumption of the Kaya Polytechnic University Centre will be carried out, and the data will then be used in the simulator to observe the behaviour of the PV-Lion system. The results obtained indicate that lithium-ion batteries can effectively meet the centre’s energy demand. In addition, it was observed that lithium-ion batteries perform better under high energy demand than the other battery technologies studied. Successive storage systems with the same capacity but different battery technologies were compared. It was found that these storage systems can handle a maximum power of 4 × 10<sup>5</sup> W for lead-acid batteries, 6.5 × 10<sup>5</sup> W for nickel-cadmium batteries, 8.5 × 10<sup>5</sup> W for nickel-metal-hydride batteries, and more than 10 × 10<sup>5</sup> W for lithium-ion technology. 展开更多
关键词 Photovoltaic Energy Energy Storage Lithium-Ion accumulator MODELING MATLAB/Simulink Simulation
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ACCUMULATOR的风险定量问题研究
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作者 陈尔瑞 《汕头大学学报(人文社会科学版)》 2015年第6期69-74,97,共6页
以深南电与国际投行对赌原油价格的ACCUMULATOR合约为典型案例,通过对此复杂的结构期权重新进行分解和组合,构造出能用布莱克-斯科尔斯模型计算的新期权组合,并具体给出ACCUMULATOR的一种风险定量计算方法。
关键词 accumulator 结构期权 风险 定量问题
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Characteristics of Cd uptake and accumulation in two Cd accumulator oilseed rape species 被引量:11
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作者 RUShu-hua WANGJi-qing SUDe-chun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期594-598,共5页
Two pot experiments were conducted under greenhouse conditions to investigate the characteristics of Cd uptake and accumulation by two Cd accumulator oilseed rape varieties and one Indian mustard grown on a loamy soil... Two pot experiments were conducted under greenhouse conditions to investigate the characteristics of Cd uptake and accumulation by two Cd accumulator oilseed rape varieties and one Indian mustard grown on a loamy soil that had been artificially contaminated by different amounts of CdSO\-4(0, 20, 40, 60, 80, 100 mg/kg soil). The relationship between shoot Cd uptake of the two oilseed rape cultivars and the soil Cd concentrations could be simulated via quadratic equations. The curve showed that maximum shoot Cd uptake of Indian mustard was 314.7 μg/pot at soil Cd concentration of 87.8 mg/kg, while maximum uptake of the variety Xikou Huazi was 543.3 μg/pot at soil Cd concentration of 69.1 mg/kg and that of the variety Zhongyou Za-1hao was 576.7 μg/pot at soil Cd concentration of 84.0 mg/kg, suggesting that shoot Cd uptake ability of the two Cd accumulator oilseed rapes was significantly higher than that of the Indian mustard. Xikou Huazi had higher phytoremediation potential for Cd contaminated soil. Shoot Cd accumulation ability of the two Cd accumulator oilseed rapes was correspond and Cd was easier translocated to the shoot than hyperaccumulator Indian mustard as comparation plant. Shoot Cd distribution pattern showed consistent and significant reduction from older leaves to younger ones of two oilseed rapes and Indian mustard. Cd uptake by oilseed rapes in growth prophase was higher than that of growth anaphase. 展开更多
关键词 Cd accumulator oilseed rape UPTAKE accumulate CHARACTERISTICS
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Weld extraction from real-time radiograph based on bidirectional accumulator Hough Transform 被引量:2
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作者 邵家鑫 都东 +2 位作者 石涵 常保华 王力 《China Welding》 EI CAS 2011年第3期6-11,共6页
An effective approach is presented to extract welds from real-time radiographs, Firstly an algorithm based on an adaptive bidirectional threshold was proposed to segment the gradient image into ternary image, and then... An effective approach is presented to extract welds from real-time radiographs, Firstly an algorithm based on an adaptive bidirectional threshold was proposed to segment the gradient image into ternary image, and then the bidirectional accumulator Hough Transform was developed to extract weld edges from the ternary image. Different values of the coefficient proposed in the threshold algorithm were tested, and the proposed approach was applied to extract welds from real-time radiographic images of different types of welds with defects. Results show that the proposed method is adaptive and effective to extract welds from real-time radiographs of linear welds. 展开更多
关键词 real-time radiographic image weld extraction adaptive threshold bidirectional accumulator Hough Transform
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Neutral and accumulator species in determining the spatial structure of tree species at different spatial scales 被引量:1
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作者 Jie Gao Chengyu Lü Yanhong Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2175-2183,共9页
In 2014,a 40-ha undisturbed plot was established in the Beijing Songshan Nature Reserve.The spatial distribution and spatial associations of five dominant tree species of different height classes were examined using s... In 2014,a 40-ha undisturbed plot was established in the Beijing Songshan Nature Reserve.The spatial distribution and spatial associations of five dominant tree species of different height classes were examined using spatial point pattern analysis and the effects of these species on local community diversity assemblages were examined using the ISAR method.The dominant species were characterized by an aggregated distribution at spatial scales of 0–50 m.At smaller spatial scales,trees in larger height classes had significant positive and negative effects on the diversity of the lower height classes.However,at larger spatial scales this effect was diminished.At small scales(0–10 m),accumulator species had positive effects on species diversity,maintained an over-representative proportion of diversity in their proximity,and supported the ecological niche theory.At the larger scale(10–50 m),neutral species were dominant and had positive effects on species diversity,though repeller species,which had negative effects on species diversity,also contributed to diversity.Neutral and accumulator species together determined local species diversity,but the relative importance of the two was closely related to spatial scale.A combination of the ecological niche theory and neutral processes together determines species coexistence and biodiversity of an undisturbed pine forest. 展开更多
关键词 The 40-ha natural Chinese PINE forest Spatial scale ISAR model SPECIES COEXISTENCE NEUTRAL and accumulator SPECIES
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CONSTANT WORK-POINT CONTROL FOR PARALLEL HYBRID SYSTEM WITH CAPACITOR ACCUMULATOR IN HYDRAULIC EXCAVATOR 被引量:4
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作者 ZHANG Yanting WANG Qingfeng XIAO Qing FU Qiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期505-508,共4页
Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hyb... Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments. 展开更多
关键词 Hybrid Hydraulic excavator Capacitor accumulator Constant work-point control Double work-point control
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Accumulator-Based Deep-Sea Microbe Gastight Sampling Technique 被引量:1
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作者 黄中华 刘少军 金波 《China Ocean Engineering》 SCIE EI 2006年第2期335-342,共8页
The accumulator is used as a pressure compensation device to realize deep-sea microbe gastight sampling. Four key states of the accumulator are proposed to describe the pressure compensation process and a correspondin... The accumulator is used as a pressure compensation device to realize deep-sea microbe gastight sampling. Four key states of the accumulator are proposed to describe the pressure compensation process and a corresponding mathematical model is established to investigate the relationship between the results of pressure compensation and the parameters of the accumulator. Simulation results show that during the falling process of the sampler, the accumulator' s real opening pressure is greater than its precharge pressure; when the sampling depth is 6000 m and the accumulator' s precharge pressure is less than 30 MPa, to increase the accumulator' s precharge pressure can improve pressure compensation results obviously. Laboratory experiments at 60 MPa show that the acctunulator is an effective and reliable pressure compensation device for deep-sea microbe samplers, The success in sea trial at a depth of 2000 m in the South China Sea shows that the mathematical model and laboratory experiment results are reliable. 展开更多
关键词 gastight sampling technique deep-sea microbe accumulator
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ANALYSES OF ENERGY LOSSES AND ACCUMULATOR AND PARAMETERS DESIGN METHOD OF HYDRAULIC IMPACTOR MECHANISM 被引量:1
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作者 Qinghua, He 《中国有色金属学会会刊:英文版》 EI CSCD 1995年第3期140-146,共7页
ANALYSESOFENERGYLOSSESANDACCUMULATORANDPARAMETERSDESIGNMETHODOFHYDRAULICIMPACTORMECHANISM¥He,Qinghua(Departm... ANALYSESOFENERGYLOSSESANDACCUMULATORANDPARAMETERSDESIGNMETHODOFHYDRAULICIMPACTORMECHANISM¥He,Qinghua(DepartmentofMechanicalEn... 展开更多
关键词 volume EFFICIENCY mechanical EFFICIENCY total EFFICIENCY accumulator DESIGN
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Effects of Accumulator on Stabilization of Direct Acting Poppet Valve and Its System
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作者 李中复 《International Journal of Mining Science and Technology》 SCIE EI 1998年第1期80-83,共4页
The effect of vibration attenuation hy installing accumulator for water pressure system with the direct acting poppet valve is studied. The influencing factors of accumulator on the stabilization of direct acing poppe... The effect of vibration attenuation hy installing accumulator for water pressure system with the direct acting poppet valve is studied. The influencing factors of accumulator on the stabilization of direct acing poppet valve and the system are analyzed. 展开更多
关键词 stability CHARACTERISTIC EQUATION accumulator
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MOTION ANALYSIS AND DESIGN OF ACCUMULATOR FOR HYDRAULIC ROCK DRILL
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作者 Liu Shixun(College of Mechanical and Electrical Engineering, Central South University of Technology, Changsha 410083) 《中国有色金属学会会刊:英文版》 CSCD 1996年第2期148-151,共4页
MOTIONANALYSISANDDESIGNOFACCUMULATORFORHYDRAULICROCKDRILLLiuShixun(CollegeofMechanicalandElectricalEngineeri... MOTIONANALYSISANDDESIGNOFACCUMULATORFORHYDRAULICROCKDRILLLiuShixun(CollegeofMechanicalandElectricalEngineering,CentralSouthUn... 展开更多
关键词 HYDRAULIC accumulator DIAPHRAGM service life STRETCHING ratio parameter design motion analvsis
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Optimal Control of a Thermoelectric Generator Attached with a Latent Heat Accumulator
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作者 Akira Tsuyoshi 《Journal of Power and Energy Engineering》 2017年第4期1-8,共8页
Generally MPPT control (maximum power point tracking) is adopted to control of a thermoelectric generator. However, in the case of generation by use of a heat accumulator MPPT control cannot obtain maximum whole elect... Generally MPPT control (maximum power point tracking) is adopted to control of a thermoelectric generator. However, in the case of generation by use of a heat accumulator MPPT control cannot obtain maximum whole electrical output during the operation period. This is because the amount of heat stored in a heat accumulator is limited and easy to be exhausted rapidly by MPPT. Therefore MEPT (Maximum Efficiency Point Tracking) control should be developed to obtain maximum power from limited heat stored in the heat accumulator. When thermoelectric generator is used for waste heat recovery, conversion efficiency is quite difficult to be measured. This is due to time delay between the change of temperature profile in the thermoelectric generator and the change of heat medium temperature. Decrease of output current is desired to enlarge output because decrease of current decreases Peltier heat and improves efficiency of heat recovery. The experimental results indicate that current fluctuated by MPPT control causes loss of power output. We proposed the optimal control in which current is 10% smaller than one of MPPT control and evaluated it experimentally. We call this control scheme MEPT control. In this evaluation 500 W class thermoelectric generator, latent heat accumulator and the test facilities included 30 kW electric heater are utilized. Experimental result shows MEPT control exceeds MPPT in total electricity recovered from heat accumulator. 展开更多
关键词 THERMOELECTRIC GENERATOR Heat accumulator MPPT MEPT
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Testing Research of Accumulator Performance in the Hydro-pneumatic Suspension of a Vehicle
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作者 FENG Shi cai, XU Yong, LU Hong yu Industrial College of Xuzhou Normal University, Jiangsu 221011, P.R.China 《International Journal of Plant Engineering and Management》 2001年第3期118-123,共6页
Taking a 2.5 liter accumulator with hydro-pneumatic suspension in a CXP1032 crane made in Germany as the research object and taking both the overall-road simulative test-bed and the control equipment made by the Schen... Taking a 2.5 liter accumulator with hydro-pneumatic suspension in a CXP1032 crane made in Germany as the research object and taking both the overall-road simulative test-bed and the control equipment made by the Schenck Company of Germany as the testing instrument, the structure performance and mechanism are theoretically clarified and the variation of gas states are obtained. This illustrates the accumulating and releasing process of a 2.5 liter accumulator in a 32t crane in the real condition. The preliminary volume and pressure of accumulator would directly affect the stiffness performance of the hydro-pneumatic suspension in a vehicle. 展开更多
关键词 hydro-pneumatic suspension accumulator performance testing changing expo-nent
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Blockchain state channels with compact states through the use of RSA accumulators
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作者 Lydia Negka Angeliki Katsika +1 位作者 Georgios Spathoulas Vassilis Plagianakos 《Blockchain(Research and Applications)》 2023年第1期71-89,共19页
One of the major concerns regarding currently proposed public blockchain systems relates to the feasible transaction processing rate.It is common for such systems to limit this rate to maintain the required levels of ... One of the major concerns regarding currently proposed public blockchain systems relates to the feasible transaction processing rate.It is common for such systems to limit this rate to maintain the required levels of security and decentralisation.State channels are an approach to overcome this limitation,as they aim to decrease the required on-chain transactions for a given application and thus indirectly increase the capacity(in terms of applications)of public blockchain systems.In the present paper,we propose a state channel design that,through the use of RSA accumulators,operates on a compact state structure.This scheme is optimal for applications whose state includes large sets of elements.The novel state channel design is presented by analysing all state channel operations and how they have to be revised.The security of the design is discussed,while a practical use case scenario regarding the use of the design for an on-chain asset(e.g.,non-fungible tokens)exchange application is also analysed. 展开更多
关键词 Blockchain State channels accumulators Layer 2 NFTs
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Effect of phosphorus on arsenic accumulation in As-hyperaccumulator Pteris vittata L. and its implication 被引量:35
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作者 Tongbin Chen Zhilian Fan +2 位作者 Mei Lei Zechun Huang Chaoyang Wei 《Chinese Science Bulletin》 SCIE EI CAS 2002年第22期1876-1879,共4页
Pot experiment was conducted to understand the effect of phosphorus on arsenic accumulation in As-hyperaccumulator Chinese brake (Pteris vittata L.). It is shown that arsenic concentrations in the fronds and rhizoids,... Pot experiment was conducted to understand the effect of phosphorus on arsenic accumulation in As-hyperaccumulator Chinese brake (Pteris vittata L.). It is shown that arsenic concentrations in the fronds and rhizoids, the arsenic bioaccumulation factor, and the total arsenic in the fronds were not influenced significantly under low levels of phosphorus (≤400 mg/kg) and increased sharply under high levels of phosphorus (】400 mg/ kg). The discovery implies that the efficiency of arsenic removal in phytoremedia-tion using the hyperaccumulating plant can be greatly elevated by the phosphorus addition at high rates. The interaction between the accumulation of phosphorus and that of arsenic in plant was stimulated mutually. The result represents that Chinese brake is a good material for plant physiologist to conduct comparative and mechanism studies on the uptake behaviors of phosphorus and arsenic, and phosphorus is also a potential accelerator for phytoremediation of arsenic-contaminated soils. 展开更多
关键词 Chinese BRAKE (Pteris vittata L.) HYPERaccumulator ARSENIC phosphorus accumulation.
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Lagrangian coherent structure analysis on transport of Acetes chinensis along coast of Lianyungang,China 被引量:1
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作者 Kexin WANG Xueqing ZHANG +2 位作者 Qi LOU Xusheng XIANG Ying XIONG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期345-359,共15页
Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the... Spatial heterogeneity or“patchiness”of plankton distributions in the ocean has always been an attractive and challenging scientific issue to oceanographers.We focused on the accumulation and dynamic mechanism of the Acetes chinensis in the Lianyungang nearshore licensed fishing area.The Lagrangian frame approaches including the Lagrangian coherent structures theory,Lagrangian residual current,and Lagrangian particle-tracking model were applied to find the transport pathways and aggregation characteristics of Acetes chinensis.There exist some material transport pathways for Acetes chinensis passing through the licensed fishing area,and Acetes chinensis is easy to accumulate in the licensed fishing area.The main mechanism forming this distribution pattern is the local circulation induced by the nonlinear interaction of topography and tidal flow.Both the Lagrangian coherent structure analysis and the particle trajectory tracking indicate that Acetes chinensis in the licensed fishing area come from the nearshore estuary.This work contributed to the adjustment of licensed fishing area and the efficient utilization of fishery resources. 展开更多
关键词 plankton accumulation hydrodynamic model Lagrangian particle-tracking model Lagrangian analysis
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Aluminum-activated Oxalate Secretion does not Associate with Internal Content among Some Oxalate Accumulators 被引量:4
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作者 Jian Li Yang LeiZhang Shao Jian Zheng 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第9期1103-1107,共5页
Although aluminum (AI)-activated secretion of oxalate has been considered to be an important AI-exclusion mechanism, whether it is a general response in oxalate accumulators and related to oxalate content in roots a... Although aluminum (AI)-activated secretion of oxalate has been considered to be an important AI-exclusion mechanism, whether it is a general response in oxalate accumulators and related to oxalate content in roots are still not clear. Here, we examined the oxalate secretion and oxalate content in some oxalate accumulators, and investigated the role of oxalate secretion in AI resistance. When oxalate content in amaranth roots was decreased by about 50% with the increased ratio of NH4^+-N to NO3^- -N in nutrient solution, the amount of AI-activated oxalate secretion still remained constant. There was no relationship between the content of the water soluble oxalate in four species of oxalate accumulators and the amount of the AI-activated oxalate secretion in roots. Furthermore, oxalate secretion is poorly associated with AI resistance among these species. Based on the above results, we concluded that although all of the oxalate accumulators tested could secrete oxalate rapidly, the density of anion channels in plasma membrane may play a more important role in AI-activated oxalate secretion. 展开更多
关键词 aluminum toxicity AMARANTHUS anion channel oxalate accumulator oxalate secretion
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Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin
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作者 Wen-Yang Wang Xiong-Qi Pang +3 位作者 Ya-Ping Wang Zhang-Xin Chen Fu-Jie Jiang Ying Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期115-124,共10页
With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can b... With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum geology.Since it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the DLOA.Hence,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the depth.In this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained collectively.The depth corresponding to a dry layer ratio of 100%is the DLOA.Based on this,a quantitative prediction model for the DLOA was finally built.The results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep layer.The critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the reservoir.The depth of the DLOA was 9,000 m.This study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling. 展开更多
关键词 Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model
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Barley Protein LFBEP-C1 from Lactiplantibacillus plantarum dy-1 Fermented Barley Extracts by Inhibiting Lipid Accumulation in a Caenorhabditis elegans Model
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作者 ZHANG Jia Yan LIU Meng Ting +4 位作者 LIU Yu Hao DENG Huan BAI Juan XIE Jian Hua XIAO Xiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期377-386,共10页
Objective This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans(C.elegans).Methods In this study,the fermented barley protein LFBEP-C1 was prepared and test... Objective This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans(C.elegans).Methods In this study,the fermented barley protein LFBEP-C1 was prepared and tested for its potential anti-obesity effects on C.elegans.The worms were fed Escherichia coli OP50(E.coli OP50),glucose,and different concentrations of LFBEP-C1.Body size,lifespan,movement,triglyceride content,and gene expression were analyzed.The results were analyzed using ANOVA and Tukey's multiple comparison test.Results Compared with the model group,the head-swing frequency of C.elegans in the group of LFBEP-C1 at 20μg/mL increased by 33.88%,and the body-bending frequency increased by 27.09%.This indicated that LFBEP-C1 improved the locomotive ability of C.elegans.The average lifespan of C.elegans reached 13.55 days,and the body length and width of the C.elegans decreased after LFBEP-C1 intake.Additionally,LFBEP-C1 reduced the content of lipid accumulation and triglyceride levels.The expression levels of sbp-1,daf-2,and mdt-15 significantly decreased,while those of daf-16,tph-1,mod-1,and ser-4 significantly increased after LFBEP-C1 intake.Changes in these genes explain the signaling pathways that regulate lipid metabolism.Conclusion LFBEP-C1 significantly reduced lipid deposition in C.elegans fed a high-glucose diet and alleviated the adverse effects of a high-glucose diet on the development,lifespan,and exercise behavior of C.elegans.In addition,LFBEP-C1 regulated lipid metabolism mainly by mediating the expression of genes in the sterol regulatory element-binding protein,insulin,and 5-hydroxytryptamine signaling pathways. 展开更多
关键词 LFBEP-C1 FERMENTATION Protein Caenorhabditis elegans Lipid accumulation Signaling pathway
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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment
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作者 A.Ajay Kumar Ch.Ashok 《Acta Geochimica》 EI CAS CSCD 2024年第1期110-133,共24页
The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are presented.In order to understand its physicoch... The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are presented.In order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical systematics.Studies of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),respectively.The mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary biotites.Although biotites from the Armoor granites generally exhibit an I-type trend,with calc-alkaline parental magma in a subduction setting.Biotite chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing conditions.Temperature and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,respectively.Geochemically,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich granite.On the chondrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high pressures.The examined granites show that they are produced from the melting of crustal sources.Thus,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting. 展开更多
关键词 Armoor granites Oxygen fugacity Crystal accumulation REMELTING SUBDUCTION
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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture
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作者 Maria Kaleem Erum Bashir +2 位作者 Shahid Naseem Tahir Rafique Bushra Shahab 《Acta Geochimica》 EI CAS CSCD 2024年第2期214-234,共21页
This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by mu... This study is thefirst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical data.The outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the region.Twenty-five soil samples were collected,mainly from the arable land of the Porali Plain.After drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric analysis.Esti-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial distribution.The granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt type.Weathering indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of alteration.These indices reflect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr ratios.Assessment of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the soils.The correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type mineralization.Weathering may result in the undesirable accumulation of certain trace elements which adversely affects crops. 展开更多
关键词 Weathering indices Pollution indices ACCUMULATION Repercussions Trace elements Multivariate analyses Porali Plain BALOCHISTAN
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