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Improved Arithmetic Optimization Algorithm with Multi-Strategy Fusion Mechanism and Its Application in Engineering Design
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作者 Yu liu Minge Chen +3 位作者 Ran Yin jianwei li Yafei Zhao Xiaohua Zhang 《Journal of Applied Mathematics and Physics》 2024年第6期2212-2253,共42页
This article addresses the issues of falling into local optima and insufficient exploration capability in the Arithmetic Optimization Algorithm (AOA), proposing an improved Arithmetic Optimization Algorithm with a mul... This article addresses the issues of falling into local optima and insufficient exploration capability in the Arithmetic Optimization Algorithm (AOA), proposing an improved Arithmetic Optimization Algorithm with a multi-strategy mechanism (BSFAOA). This algorithm introduces three strategies within the standard AOA framework: an adaptive balance factor SMOA based on sine functions, a search strategy combining Spiral Search and Brownian Motion, and a hybrid perturbation strategy based on Whale Fall Mechanism and Polynomial Differential Learning. The BSFAOA algorithm is analyzed in depth on the well-known 23 benchmark functions, CEC2019 test functions, and four real optimization problems. The experimental results demonstrate that the BSFAOA algorithm can better balance the exploration and exploitation capabilities, significantly enhancing the stability, convergence mode, and search efficiency of the AOA algorithm. 展开更多
关键词 Arithmetic Optimization Algorithm Adaptive Balance Factor Spiral Search Brownian Motion Whale Fall Mechanism
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Pseudo-Semi-Overlap Functions-Based Fuzzy Rough Sets Applied to Image Edge Extraction
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作者 Ran Yin Minge Chen +2 位作者 Yu liu Yafei Zhao jianwei li 《Journal of Applied Mathematics and Physics》 2024年第7期2347-2366,共20页
As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and furth... As an extension of overlap functions, pseudo-semi-overlap functions are a crucial class of aggregation functions. Therefore, (I, PSO)-fuzzy rough sets are introduced, utilizing pseudo-semi-overlap functions, and further extended for applications in image edge extraction. Firstly, a new clustering function, the pseudo-semi-overlap function, is introduced by eliminating the symmetry and right continuity present in the overlap function. The relaxed nature of this function enhances its applicability in image edge extraction. Secondly, the definitions of (I, PSO)-fuzzy rough sets are provided, using (I, PSO)-fuzzy rough sets, a pair of new fuzzy mathematical morphological operators (IPSOFMM operators) is proposed. Finally, by combining the fuzzy C-means algorithm and IPSOFMM operators, a novel image edge extraction algorithm (FCM-IPSO algorithm) is proposed and implemented. Compared to existing algorithms, the FCM-IPSO algorithm exhibits more image edges and a 73.81% decrease in the noise introduction rate. The outstanding performance of (I, PSO)-fuzzy rough sets in image edge extraction demonstrates their practical application value. 展开更多
关键词 Pseudo-Semi-Overlap Functions Fuzzy Rough Set Fuzzy Mathematical Morphology Image Edge Extraction
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Facile construction of a multilayered interface for a durable lithium‐rich cathode
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作者 Zhou Xu Yifei Yuan +8 位作者 Qing Tang Xiangkun Nie jianwei li Qing Sun Naixuan Ci Zhenjie Xi Guifang Han lijie Ci Guanghui Min 《Carbon Energy》 SCIE EI CAS CSCD 2023年第9期74-87,共14页
Layered lithium-rich manganese-based oxide(LRMO)has the limitation of inevitable evolution of lattice oxygen release and layered structure transformation.Herein,a multilayer reconstruction strategy is applied to LRMO ... Layered lithium-rich manganese-based oxide(LRMO)has the limitation of inevitable evolution of lattice oxygen release and layered structure transformation.Herein,a multilayer reconstruction strategy is applied to LRMO via facile pyrolysis of potassium Prussian blue.The multilayer interface is visually observed using an atomic-resolution scanning transmission electron microscope and a high-resolution transmission electron microscope.Combined with the electrochemical characterization,the redox of lattice oxygen is suppressed during the initial charging.In situ X-ray diffraction and the high-resolution transmission electron microscope demonstrate that the suppressed evolution of lattice oxygen eliminates the variation in the unit cell parameters during initial(de)lithiation,which further prevents lattice distortion during long cycling.As a result,the initial Coulombic efficiency of the modified LRMO is up to 87.31%,and the rate capacity and long-term cycle stability also improved considerably.In this work,a facile surface reconstruction strategy is used to suppress vigorous anionic redox,which is expected to stimulate material design in high-performance lithium ion batteries. 展开更多
关键词 lattice oxygen release lithium‐rich manganese‐based oxide cathodes reconstructed multilayer interface spinel phase transition‐metal ion migration
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HuR-mediated nucleocytoplasmic translocation of HOTAIR relieves its inhibition of osteogenic differentiation and promotes bone formation
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作者 Yuheng li Weijia Sun +15 位作者 jianwei li Ruikai Du Wenjuan Xing Xinxin Yuan Guohui Zhong Dingsheng Zhao Zizhong liu Xiaoyan Jin Junjie Pan Youyou li Qi li Guanghan Kan Xuan Han Shukuan ling Xiqing Sun Yingxian li 《Bone Research》 SCIE CAS CSCD 2023年第4期803-818,共16页
Bone marrow mesenchymal stem cell(BMSC)osteogenic differentiation and osteoblast function play critical roles in bone formation,which is a highly regulated process.Long noncoding RNAs(lncRNAs)perform diverse functions... Bone marrow mesenchymal stem cell(BMSC)osteogenic differentiation and osteoblast function play critical roles in bone formation,which is a highly regulated process.Long noncoding RNAs(lncRNAs)perform diverse functions in a variety of biological processes,including BMSC osteogenic differentiation.Although several studies have reported that HOX transcript antisense RNA(HOTAIR)is involved in BMSC osteogenic differentiation,its effect on bone formation in vivo remains unclear.Here,by constructing transgenic mice with BMSC(Prx1-HOTAIR)-and osteoblast(Bglap-HOTAIR)-specific overexpression of HOTAIR,we found that Prx1-HOTAIR and Bglap-HOTAIR transgenic mice show different bone phenotypes in vivo.Specifically,Prx1-HOTAIR mice showed delayed bone formation,while Bglap-HOTAIR mice showed increased bone formation.HOTAIR inhibits BMSC osteogenic differentiation but promotes osteoblast function in vitro.Furthermore,we identified that HOTAIR is mainly located in the nucleus of BMSCs and in the cytoplasm of osteoblasts.HOTAIR displays a nucleocytoplasmic translocation pattern during BMSC osteogenic differentiation.We first identified that the RNA-binding protein human antigen R(HuR)is responsible for HOTAIR nucleocytoplasmic translocation.HOTAIR is essential for osteoblast function,and cytoplasmic HOTAIR binds to miR-214 and acts as a ceRNA to increase Atf4 protein levels and osteoblast function.BglapHOTAIR mice,but not Prx1-HOTAIR mice,showed alleviation of bone loss induced by unloading.This study reveals the importance of temporal and spatial regulation of HOTAIR in BMSC osteogenic differentiation and bone formation,which provides new insights into precise regulation as a target for bone loss. 展开更多
关键词 HOTAIR PRECISE function
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Instrument Automation Control System Faults and Maintenance
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作者 jianwei li 《Journal of Electronic Research and Application》 2024年第1期16-21,共6页
This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and re... This article explores the topic of fault diagnosis and maintenance strategies for instrument automation control systems,analyzing them through specific cases.The aim of this research is to improve the stability and reliability of the system by conducting a thorough investigation of faults and maintenance in instrument automation control systems.By doing so,this research hopes to provide a strong guarantee for the smooth progress of industrial production. 展开更多
关键词 Instrument automation Control system failure Maintenance
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Source and possible tectonic driver for Jurassic-Cretaceous gold deposits in the West Qinling Orogen, China 被引量:3
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作者 Yafei Wu jianwei li +2 位作者 Katy Evans Denis Fougerouse Kirsten Rempel 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第1期107-117,共11页
The West Qinling Orogen(WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits(>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Tria... The West Qinling Orogen(WQO) in Central China Orogenic Belt contains numerous metasedimentary rock-hosted gold deposits(>2000 t Au), which mainly formed during two pulses: one previously recognized in the Late Triassic to Early Jurassic(T3 - J1) and one only recently identified in the Late Jurassic to Early Cretaceous(J3 - K1). Few studies have focused on the origin and geotectonic setting of the J3 - K1 gold deposits.Textural relationships, LA-ICP-MS trace element and sulfur isotope compositions of pyrites in hydrothermally altered T3 dykes within the J3 - K1 Daqiao deposit were used to constrain relative timing relationships between mineralization and pyrite growth in the dykes, and to characterize the source of ore fluid. These results are integrated with an overview of the regional geodynamic setting, to advance understanding of the tectonic driver for J3 - K1 hydrothermal gold systems. Pyrite in breccia-and dykehosted gold ores at Daqiao have similar chemical and isotopic compositions and are considered to be representative of J3 - K1 gold deposits in WQO. Co/Ni and sulfur isotope ratios suggest that ore fluids were derived from underlying Paleozoic Ni-and Se-rich carbonaceous sedimentary rocks. The geochemical data do not support the involvement of magmatic fluids. However, in the EQO(East Qinling Orogen), J3 - K1 deposits are genetically related to magmatism. Gold mineralization in WQO is contemporaneous with magmatic deposits in the EQO and both are mainly controlled by NE-and EWtrending structures produced by changes in plate motion of the Paleo-Pacific plate as it was subducted beneath the Eurasian continent. We therefore infer that the J3 - K1 structural regime facilitated the ascent of magma in the EQO and metamorphic fluids in the WQO with consequent differences in the character of contemporaneous ore deposits. If this is correct, then the far-field effects of subduction along the eastern margin of NE Asia extended 1000's of km into the continental interior. 展开更多
关键词 Pyrite LA-ICP-MS Sulfur isotopes Daqiao gold deposit West Qinling Orogen Paleo-Pacific plate Jurassice Cretaceous
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Removal of mercaptans from light oils using ionic liquid–NaOH aqueous solution as extractants 被引量:1
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作者 jianwei li Xiang li +1 位作者 Yan liu Jie Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第2期171-174,共4页
The application of ionic liquids as alternatives to conventional organic solvents in the extraction process has been investigated. In the present study, fourteen species of imidazolium-based ionic liquids were added i... The application of ionic liquids as alternatives to conventional organic solvents in the extraction process has been investigated. In the present study, fourteen species of imidazolium-based ionic liquids were added into the Na OH(aq) to remove the mercaptans. The influences of anion species and cation alkyl chain length of the imidazolium-based ionic liquids on the performance of mercaptan removal from light oils have been discussed.The efficiency of extraction for mercaptans exhibited the order of [Ac]^-N [OH]^-≈ [Br]^-N [BF4]^-. The longer alkyl chain imidazolium-based ionic liquids contributed to enhance desulfurization rate of 1-butyl mercaptan.100% desulfurization rate of 1-butyl mercaptan was achieved by the anion of Ac-ionic liquids and Na OH(aq)at a volume ratio of 40:1(V(oil):V(ionic liquid)) and a short equilibrium time within 10 min. 展开更多
关键词 离子液体 轻质油品 氢氧化钠水溶液 脱硫醇 萃取剂 脱除 NAOH 咪唑类
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Techno-economic analysis of MJ class high temperature Superconducting Magnetic Energy Storage(SMES) systems applied to renewable power grids 被引量:3
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作者 Jiahui Zhu Panpan Chen +7 位作者 Chenghong Gu Hongjie Zhang jianwei li Huiming Zhang Ming Qiu Jianlin li Weijia Yuan Ignacio Hernando Gil 《Global Energy Interconnection》 2018年第2期172-178,共7页
High temperature Superconducting Magnetic Energy Storage(SMES) systems can exchange energy with substantial renewable power grids in a small period of time with very high efficiency. Because of this distinctive featur... High temperature Superconducting Magnetic Energy Storage(SMES) systems can exchange energy with substantial renewable power grids in a small period of time with very high efficiency. Because of this distinctive feature, they store the abundant wind power when the power network is congested and release the energy back to the system when there is no congestion. However, considering the cost and lifespan of SMES systems, there is an urgent demand to conduct a cost-benefit analysis to justify its role in smart grid development. This study explores the application and performs economic analysis of a 5 MJ SMES in a practical renewable power system in China based on the PSCAD/EMTDC software. An optimal location of SMES in Zhangbei wind farm is presented using real power transmission parameters. The stabilities of the renewable power grid with and without SMES are discussed. In addition, a financial feasibility study is conducted by comparing the cost and the savings from wind power curtailment of deploying SMES and battery. The economic analysis tries to find the balance between SMES investment cost and wind farm operation cost by using real data over a calendar year. The technical analysis can help guide the optimal allocation of SMES for compensating power system instability with substantial wind power. Further, the economic analysis provides a useful indication of its practical application feasibility to fight the balance between cost and benefit. 展开更多
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Effect of grain refinement induced by wire and arc additive manufacture (WAAM) on the corrosion behaviors of AZ31 magnesium alloy in NaCl solution 被引量:8
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作者 jianwei li Youmin QIU +9 位作者 Junjie YANG Yinying SHENG Yanliang YI Xun ZENG lianxi CHEN Fengliang YIN Jiangzhou SU Tiejun ZHANG Xin TONG Bin GUO 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第1期217-229,共13页
Additive manufacturing(AM)of Mg alloys has become a promising strategy for producing complex structures,but the corrosion performance of AM Mg components remains unexploited.In this study,wire and arc additive manufac... Additive manufacturing(AM)of Mg alloys has become a promising strategy for producing complex structures,but the corrosion performance of AM Mg components remains unexploited.In this study,wire and arc additive manufacturing(WAAM)was employed to produce single AZ31 layer.The results revealed that the WAAM AZ31 was characterized by significant grain refinement with non-textured crystallographic orientation,similar phase composition and stabilized corrosion performance comparing to the cast AZ31.These varied corrosion behaviors were principally ascribed to the size of grain,where cast AZ31 and WAAM AZ31 were featured by micro galvanic corrosion and intergranular corrosion,respectively. 展开更多
关键词 AZ31 magnesium alloy Wire and arc additive manufacturing(WAAM) Grain refinement Microstructure Intergranular corrosion
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Trace Amounts of Triple-Functional Additives Enable Reversible Aqueous Zinc-Ion Batteries from a Comprehensive Perspective 被引量:4
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作者 Ruwei Chen Wei Zhang +12 位作者 Quanbo Huang Chaohong Guan Wei Zong Yuhang Dai Zijuan Du Zhenyu Zhang jianwei li Fei Guo Xuan Gao Haobo Dong Jiexin Zhu Xiaohui Wang Guanjie He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期143-154,共12页
Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on th... Although their cost-effectiveness and intrinsic safety,aqueous zinc-ion batteries suffer from notorious side reactions including hydrogen evolution reaction,Zn corrosion and passivation,and Zn dendrite formation on the anode.Despite numerous strategies to alleviate these side reactions have been demonstrated,they can only provide limited performance improvement from a single aspect.Herein,a triple-functional additive with trace amounts,ammonium hydroxide,was demonstrated to comprehensively protect zinc anodes.The results show that the shift of electrolyte pH from 4.1 to 5.2 lowers the HER potential and encourages the in situ formation of a uniform ZHS-based solid electrolyte interphase on Zn anodes.Moreover,cationic NH^(4+)can preferentially adsorb on the Zn anode surface to shield the“tip effect”and homogenize the electric field.Benefitting from this comprehensive protection,dendrite-free Zn deposition and highly reversible Zn plating/stripping behaviors were realized.Besides,improved electrochemical performances can also be achieved in Zn//MnO_(2)full cells by taking the advantages of this triple-functional additive.This work provides a new strategy for stabilizing Zn anodes from a comprehensive perspective. 展开更多
关键词 Aqueous zinc-ion battery Cationic shielding effect Solid electrolyte interphase pH value Triple-functional additive
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Oxidation of benzene to phenol with N_(2)O over a hierarchical Fe/ZSM-5 catalyst 被引量:1
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作者 Cui Ouyang jianwei li +2 位作者 Yaqi Qu Song Hong Songbo He 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1161-1173,共13页
Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an ox... Catalytic oxidation of benzene with N_(2)O to phenol over the hierarchical and microporous Fe/ZSM-5-based catalysts in a continuous fixedbed reactor was investigated.The spent catalyst was in-situ regenerated by an oxidative treatment using N_(2)O and in total 10 reaction-regeneration cycles were performed.A 100% N_(2)O conversion,93.3% phenol selectivity,and high initial phenol formation rate of 16.49±0.06mmol_(phenol gcatalyst)^(-1)h^(-1)at time on stream(TOS) of 5 min,and a good phenol productivity of 147.06 mmol_(phenol gcatalyst)^(-1)during catalyst lifetime of 1800 min were obtained on a fresh hierarchical Fe/ZSM-5-Hi2.8 catalyst.With the reaction-regeneration cycle,N_(2)O conversion is fully recovered within TOS of 3 h,moreover,the phenol productivity was decreased ca.2.2±0.8% after each cycle,leading to a total phenol productivity of ca.0.44 ton_(pheol kg_(catalyst)^(-1)estimated for 300 cycles.Catalyst characterizations imply that the coke is rapidly deposited on catalyst surface in the initial TOS of 3 h(0.28 mgc_(gcatalyst)^(-1)min^(-1)) and gradually becomes graphitic during the TOS of 30 h with a slow formation rate of 0.06 mgc g_(catalyst)^(-1)min^(-1).Among others(e.g.,the decrease of textural property and acidity),the nearly complete coverage of the active Fe-O-Al sites by coke accounts for the main catalyst deactivation.Besides these reversible deactivation characteristics related to coking,the irreversible catalyst deactivation is also observed with the reaction-regeneration cycle.The latter is reflected by a further decreased amount of the active Fe-O-Al sites,which agglomerate on catalyst surface with the cycle,likely associated with the hard coke residue that is not completely removed by the regeneration. 展开更多
关键词 Hierarchical Fe/ZSM-5 N_(2)O conversion Phenol product productivity Reaction-regeneration cycles Irreversible deactivation mechanism
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Changes in blood lipid levels and influencing factors among treatment-naïve adult male HlV/AlDS patients following BlC/FTC/TAF vs.3TC+EFV+TDF
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作者 Xi Wang An liu +7 位作者 Zaicun li Hongwei Zhang Ruojun Esther Wu Ying Shao jianwei li Jiangzhu Ye Wei liu lijun Sun 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第12期1447-1452,共6页
Background:Antiretroviral therapy(ART)was often associated with dyslipidemia among human immunodeficiency virus(HIV)/acquired immunodeficiency syndrome(AIDS)patients.This study aimed to assess treatment-naïve adu... Background:Antiretroviral therapy(ART)was often associated with dyslipidemia among human immunodeficiency virus(HIV)/acquired immunodeficiency syndrome(AIDS)patients.This study aimed to assess treatment-naïve adult male patients with HIV/AIDS who initiated ART with either co-formulated bictegravir,emtricitabine,and tenofovir alafenamide(BIC/FTC/TAF)or lamivudine,efavirenz,and tenofovir disoproxil fumarate(3TC+EFV+TDF),monitoring at weeks 4,12,24,and 48.Methods:A case-control retrospective study was conducted.The newly diagnosed HIV-infected individuals attending the sexual transmission disease(STD)/AIDS clinic of Beijing Youan Hospital,Capital Medical University,from January to December 2021.The patients were divided into BIC/FTC/TAF group or 3TC+EFV+TDF group.High-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),triglyceride(TG),and total cholesterol(TC)at different time points over 48 weeks between two groups were compared.A multivariate Cox regression model was used to identify relevant influencing factors for the population at high risk of increased LDL-C.Results:A total of 870 participants,with 510 in BIC/FTC/TAF group and 360 in 3TC+EFV+TDF group.There were no statistically significant differences in median age,baseline CD4/CD8 ratio,median body mass index(BMI)between the two groups.In both two groups,levels of TG,TC,and LDL-C were higher at 4 weeks,12 weeks,and 24 weeks of treatment(all P<0.05),and there were no statistically significant differences at 48 weeks compared to those at baseline(all P>0.05).In addition,the differences in average changes of the level of TG,TC,HDL-C,and LDL-C from weeks 4,12,24,and 48 to baseline between two groups were not statistically significant(all P>0.05).Multivariate Cox proportional risk model analysis showed that initiating ART with HIV RNA≥10^(5)copies/mL(compared with<10^(5)copies/mL)was associated with an increased risk of elevated LDL-C(hazard ratio=1.26,95%confidence interval:1.07-1.48,P=0.005).Conclusions:Transient elevations in blood lipid levels(TC,TG,HDL-C,and LDL-C)were observed in treatment-naïve adult male HIV/AIDS patients with BIC/FTC/TAF at 4 weeks,12 weeks,and 24 weeks of treatment.However,these levels did not differ significantly from baseline after 48 weeks of treatment,regardless of whether patients were in the BIC/FTC/TAF or 3TC+EFV+TDF group. 展开更多
关键词 Antiretroviral therapy Blood lipids Bictegravir/emtricitabine/tenofovir alafenamide Lamivudine efavirenz and tenofovir disoproxil fumarate BIC/FTC/TAF 3TC+EFV+TDF HIV AIDS
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Monazite U-Th-Pb and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit in the Qinling orogen,central China:Implications for regional gold metallogeny
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作者 Xueling YU jianwei li +3 位作者 Xiaoye JIN Shaorui ZHAO Chongguo HE Yunlong ZHU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第8期2478-2494,共17页
The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined.Here ... The Qinling orogen in central China contains several black shale-hosted gold deposits,but the age of their formation and a possible relation between gold mineralization and regional tectonism remain undetermined.Here we present results of in situ monazite U-Th-Pb dating and sericite Rb-Sr dating of the Xiajiadian black shale-hosted gold deposit to provide tight constraints on the time of gold deposition and information on the tectonic setting under which the deposit formed.The Xiajiadian gold deposit is mainly hosted in black shales of the Lower Cambrian Shuigoukou formation,with minor ores contained in sandy conglomerate of the Lower Devonian Xichahe formation.Gold ores in the black shales have been intensively oxidized and consist mainly of hematite,goethite,gypsum,quartz,calcite,native gold,and unrecognized iron oxides.However,gold ores in the sandy conglomerate are free of oxidation and thus provide an opportunity to date the formation of the Xiajiadian gold deposit.The ores consist of pyrite,marcasite,sericite,and quartz,which are associated with a variety of accessory minerals,including monazite,apatite,and titanite.Gold is mainly present as structure-bound ions or nanoparticles in pyrite and marcasite,but minor native gold grains also occur as inclusions in pyrite.Monazite is well developed in the ores,and has close textural association with Au-bearing pyrite and marcasite.Most monazite grains have zoned textures consisting of a core area(Mnz1)and an overgrowth zone(Mnz2).Mnz1 contains 4.8–13 wt.%ThO_(2)and shows large variations in HREE and prominent negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates ranging from 910±10 to416±4 Ma(2σ).These dates are interpreted in terms of a detrital origin for monazite in the core area.Mnz2 has much lower ThO_(2)contents of 0.8–1.7 wt.%and shows weak negative Eu anomalies in the chondrite-normalized REE patterns.It yields common lead-corrected^(208)Pb/^(232)Th dates of 229–209 Ma(2σ)with a weighted mean of 217.6±3.0 Ma(2σ),which is considered as the time of Mnz2 crystallization.Sericite in gold ores and associated alteration zones has close relations to Au-bearing pyrite and marcasite,and yields a well-defined Rb-Sr isochron age of 222.2±3.3 Ma(2σ).The sericite Rb-Sr age is indistinguishable within analytical errors from the weighted mean Th-Pb age of Mnz2.The age data presented here indicate that the Xiajiadian gold deposit formed at ca.220 Ma in the Late Triassic(Norian).We therefore suggest that gold mineralization at Xiajiadian occurred during the transitional stage from oceanic subduction to continental collision that led to the formation of the Qinling orogen.During this stage,metamorphic devolatization of the underlying Early Paleozoic to Proterozoic carbonaceous sequences likely supplied ore fluids from which the Xiajiadian gold deposit formed. 展开更多
关键词 Monazite U-Th-Pb dating Sericite Rb-Sr dating Late Triassic(Norian) Orogenic gold deposit Xiajiadian
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Effect of Polyethylene (LDPE) Microplastic on Remediation of Cadmium Contaminated Soil by <i>Solanum nigrum</i>L.
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作者 Jiying Zou Chenyu Wang +6 位作者 jianwei li Jia Wei Ying liu liangyu Hu Hui liu Hongfeng Bian Dazhi Sun 《Journal of Geoscience and Environment Protection》 2022年第1期49-64,共16页
<i><span style="font-family:;" "="">Solanum nigrum</span></i><span style="font-family:;" "=""> L. has a delightful prospect as a hyperacc... <i><span style="font-family:;" "="">Solanum nigrum</span></i><span style="font-family:;" "=""> L. has a delightful prospect as a hyperaccumulation plant for cadmium pollution remediation, and microplastic is a new type of pollution that has received wide attention. In this study, the effects of polyethylene microplastics (LDPE) (0.135, 0.27, 0.81 and 1.35 mg·kg<sup>-1</sup>) and cadmium (20 mg·kg<sup>-1</sup>) on the growth indexes and soil physical and chemical properties of <i>Solanum nigrum</i> L. were investigated in a 17-day microcosm experiment. The results showed that single LDPE contamination showed a trend of low concentration promotion and medium-high concentration inhibited the growth index of <i>Solanum nigrum</i> L. and soil physicochemical index, and single Cd contamination was more stressful to plants than single LDPE contamination, while low concentration of LDPE could reduce the effect of Cd on soil physical and chemical properties and promote plant growth and uptake of soil nutrients. These findings suggest that high concentrations of microplastics can inhibit the growth of <i>Solanum nigrum</i> L. alone or in combination with Cd, rather than reducing the toxicity of Cd.</span> 展开更多
关键词 Microplastics Heavy Metal Compound Pollution PHYTOREMEDIATION Solanum nigrum L.
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陶瓷介入建筑装饰的艺术营造 被引量:2
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作者 李建伟 李高翔 《陶瓷》 CAS 2021年第9期128-129,共2页
对我国陶瓷艺术与建筑装饰,所涵盖的人文和自然内涵进行梳理,可以发现陶瓷与建筑装饰艺术的内在渊源,是建立在陶瓷的历史与人文特性、陶瓷与建筑共融的地域特性上的。把握陶瓷与建筑装饰艺术持续共生的要点,对陶瓷文化的传承和建筑装饰... 对我国陶瓷艺术与建筑装饰,所涵盖的人文和自然内涵进行梳理,可以发现陶瓷与建筑装饰艺术的内在渊源,是建立在陶瓷的历史与人文特性、陶瓷与建筑共融的地域特性上的。把握陶瓷与建筑装饰艺术持续共生的要点,对陶瓷文化的传承和建筑装饰的发展有参考意义。 展开更多
关键词 陶瓷 建筑装饰 艺术营造
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花状微球Znln_2S_4/碳量子点复合物用于光催化还原Cr(Ⅵ)(英文) 被引量:7
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作者 刘白白 刘心娟 +6 位作者 李蕾 李建伟 李灿 宫银燕 牛棱渊 赵新生 孙长庆 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第12期1901-1909,共9页
六价铬Cr(Ⅵ)是废水中常见的重金属污染物,广泛应用于电镀、皮革制造、金属表面处理、纺织制造等领域.传统的处理方法有吸附、超滤、反渗透和凝固等.但是,这些方法均具有一定的缺陷,比如膜污染、高功耗、高运行和维护成本.Cr(Ⅲ)有较低... 六价铬Cr(Ⅵ)是废水中常见的重金属污染物,广泛应用于电镀、皮革制造、金属表面处理、纺织制造等领域.传统的处理方法有吸附、超滤、反渗透和凝固等.但是,这些方法均具有一定的缺陷,比如膜污染、高功耗、高运行和维护成本.Cr(Ⅲ)有较低毒性且易在水溶液中沉淀形成Cr(OH)_3,因此,将Cr(Ⅵ)还原为Cr(Ⅲ)被认为是一种有效去除Cr(Ⅵ)的策略.近年来,半导体光催化技术广受关注,被用于去除有毒污染物、还原二氧化碳和分解水,并在光催化还原Cr(Ⅵ)领域取得一系列进展.但是,探索开发可见光响应的高效光催化剂仍是挑战.三元金属硫属元素化合物半导体具有独特的光电特性和催化活性,备受关注.尤其是窄带Znln_2S_4被认为是一种有潜力的可见光催化剂.但是,由于其较窄的光响应范围以及光生载流子短的寿命,使得它的催化活性很低.研究表明,控制形貌、掺杂贵金属和构筑异质结复合物能够提高Znln_2S_4的光催化活性.不幸的是,有关Znln_2S_4在光催化还原Cr(Ⅵ)中的应用还鲜有报道.本文通过构筑花状微球Znln_2S_4和碳量子点(CQDs)异质结,合成Znln_2S_4/CQDs复合物,获得高效光催化还原Cr(Ⅵ)活性的复合光催化剂.扫描电子显微镜和高分辨投射电子显微镜结果显示, Znln_2S_4/CQDs复合物是由花瓣自组装的花状微球结构, CQDs分散在Znln_2S_4花瓣上,形成很好的界面接触,有利于光催化过程的进行.紫外可见吸收光谱结果表明, Znln_2S_4/CQDs复合物在可见光区域展现了很好的吸收.随着CQDs含量的增加, Znln_2S_4/CQDs复合物的光吸收能力增加,有利于提高其催化活性.电化学阻抗谱、光电流响应曲线和原位电子顺磁共振谱结果表明, CQDs可以作为电子受体材料,促进光生载流子的转移,抑制其复合,从而延长光生载流子的寿命.通过光催化还原Cr(Ⅵ)的实验发现,与纯Znln_2S_4相比, Znln_2S_4/CQDs复合物具有增强的光催化活性,并且与CQDs的掺杂比例有关.在可见光照射40 min后,当CQDs的掺杂比例为0.5 wt%时, Znln_2S_4/CQDs复合物对Cr(Ⅵ)的还原率达到93%.Znln_2S_4/CQDs复合物优异的催化活性归因于其优异的光吸收,良好的界面电荷转移,和CQDs的下转换特性.另外,光催化还原Cr(Ⅵ)实验被循环3次后发现, Cr(Ⅵ)的还原率没有明显降低.同时, X射线衍射、扫描电子显微镜和光电子能谱结果表明,催化反应之后的Znln_2S_4/CQDs复合物的结构、形貌和组分均未发生变化,说明Znln_2S_4/CQDs复合物具有良好的稳定性.本工作以期为进一步设计具有理想功能的CQDs基复合材料提供有价值的信息. 展开更多
关键词 Znln2S4 碳量子点 花状微球 助催化剂 光电化学
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基于戊二胺的半芳香族耐高温尼龙的合成与表征 被引量:7
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作者 李建伟 朱国富 +7 位作者 王道波 阎昆 钟一平 韩澄光 曹民 姜苏俊 黄险波 张传辉 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2021年第9期23-31,共9页
以生物基戊二胺、己二胺和对苯二甲酸为原料,通过预聚+固相增黏工艺合成耐高温尼龙聚(对苯二甲酰戊二胺-共-己二胺)(PA5T/6T)共聚物。使用低温排水工艺有效抑制了戊二胺脱氨环化副反应,得到高黏度PA5T/6T。相对于传统耐高温尼龙(对苯二... 以生物基戊二胺、己二胺和对苯二甲酸为原料,通过预聚+固相增黏工艺合成耐高温尼龙聚(对苯二甲酰戊二胺-共-己二胺)(PA5T/6T)共聚物。使用低温排水工艺有效抑制了戊二胺脱氨环化副反应,得到高黏度PA5T/6T。相对于传统耐高温尼龙(对苯二甲酰-共-己二酰-己二胺)PA6T/66,生物基耐高温尼龙PA5T/6T具有玻璃化转变温度高(155℃vs.103℃)、热滞留保持率高(77%vs.19%)、力学性能佳和熔接痕强度高等突出优势。 展开更多
关键词 戊二胺 聚(对苯二甲酰戊二胺-共-己二胺) 环化 玻璃化转变温度
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Carbon deposition and catalytic deactivation during CO_2 reforming of CH_4 over Co/MgO catalyst 被引量:4
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作者 jianwei li Jun li Qingshan Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第11期2344-2350,共7页
The deactivation mechanism of Co/MgO catalyst for the reforming of methane with carbon dioxide was investigated. The conversion of CH4 displayed a significant decrease in the initial stage caused by carbon deposition.... The deactivation mechanism of Co/MgO catalyst for the reforming of methane with carbon dioxide was investigated. The conversion of CH4 displayed a significant decrease in the initial stage caused by carbon deposition.There were two types of cokes, carbon nanotubes(CNTs) and carbon nano-onions(CNOs). The number of the CNO layers that coated on the surface of Co nanoparticles(NPs) increased rapidly in the initial reforming time,which was responsible for the deactivation of the Co/MgO catalyst. The deposition of CNOs was attributed to the oxidation of Co NPs. Therefore, the deactivation of the Co/MgO catalyst was originated from the first oxidization of the Co NPs into Co3 O4 by O species(OH intermediate, CO_2, H2 O) during the reforming reaction,which accelerates the formation of coke that blocked the active metal, thus led to catalyst deactivation. 展开更多
关键词 Co/MgO CH4 REFORMING Carbon deposition CO OXIDIZATION
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High-performance self-assembly MnCo2O4 nanosheets for asymmetric supercapacitors 被引量:4
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作者 jianwei li Dongbin Xiong +2 位作者 linzhe Wang Maleki Kheimeh Sari Hirbod Xifei li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期66-72,共7页
In this study,MnCo2O4 nanosheets were proposed to be utilized as an electrode material for supercapacitors.A two-step hydrothermal method with post-annealing treatment was employed in preparation of the nanostructures... In this study,MnCo2O4 nanosheets were proposed to be utilized as an electrode material for supercapacitors.A two-step hydrothermal method with post-annealing treatment was employed in preparation of the nanostructures.MnCo2O4 electrode delivered a high specific capacitance of 2000 F g^-1 at 0.5 A g^-1,remarkable high-rate capability of 1150 F g^-1 at 20 A g^-1,and an excellent cycling stability of 92.3%at 5 A g^-1 after 5000 cycles.It is found that a three-electrode supercapacitor based on MnCo2O4 exhibits a promising electrochemical performance,better than the other similar materials,benefited from the synergistic effects of MnCo2O4 nanosheets.In fact,the self-assembly of nanosheets structure with high specific surface area and mesoporous structure can potentially enhance the electrochemical performance of supercapacitors. 展开更多
关键词 HIGH-PERFORMANCE SELF-ASSEMBLY MnCo2O4 NANOSHEETS ASYMMETRIC SUPERCAPACITORS
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Structural engineering of cathodes for improved Zn-ion batteries 被引量:4
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作者 Jiajia Huang Yuying li +9 位作者 Ruikuan Xie jianwei li Zhihong Tian Guoliang Chai Yanwu Zhang Feili Lai Guanjie He Chuntai liu Tianxi liu Dan J.L.Brett 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期147-155,共9页
Aqueous zinc-ion batteries(ZIBs) are attracting considerable attention because of their low cost,high safety and abundant anode material resources.However,the major challenge faced by aqueous ZIBs is the lack of stabl... Aqueous zinc-ion batteries(ZIBs) are attracting considerable attention because of their low cost,high safety and abundant anode material resources.However,the major challenge faced by aqueous ZIBs is the lack of stable and high capacity cathode materials due to their complicated reaction mechanism and slow Zn-ion transport kinetics.This study reports a unique 3 D ’flower-like’ zinc cobaltite(ZnCo_(2)O_(4-x)) with enriched oxygen vacancies as a new cathode material for aqueous ZIBs.Computational calculations reveal that the presence of oxygen vacancies significantly enhances the electronic conductivity and accelerates Zn^(2+) diffusion by providing enlarged channels.The as-fabricated batteries present an impressive specific capacity of 148.3 mAh g^(-1) at the current density of 0.05 A g^(-1),high energy(2.8 Wh kg^(-1)) and power densities(27.2 W kg^(-1)) based on the whole device,which outperform most of the reported aqueous ZIBs.Moreover,a flexible solid-state pouch cell was demonstrated,which delivers an extremely stable capacity under bending states.This work demonstrates that the performance of Zn-ion storage can be effectively enhanced by tailoring the atomic structure of cathode materials,guiding the development of low-cost and eco-friendly energy storage materials. 展开更多
关键词 Zinc cobaltite Oxygen vacancies Aqueous zinc-ion batteries Flexible solid-state pouch cell
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