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GLOBAL WEIGHTED SPACE-TIME ESTIMATES OF SMALL DATA WEAK SOLUTIONS TO 1-D SEMILINEAR WAVE EQUATIONS WITH SCALING INVARIANT DAMPINGS
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作者 qianqian li Huicheng YIN 《Acta Mathematica Scientia》 2025年第6期2330-2353,共24页
In this paper,for the 1-D semilinear wave equation∂_(t)^(2)u-∂_(x)^(2)u+μ/t∂_(t)u=|u|~p with scaling invariant damping,where t≥1,p>1 andμ∈(0,1)∪(1,4/3),we establish the global weighted space-time estimates as ... In this paper,for the 1-D semilinear wave equation∂_(t)^(2)u-∂_(x)^(2)u+μ/t∂_(t)u=|u|~p with scaling invariant damping,where t≥1,p>1 andμ∈(0,1)∪(1,4/3),we establish the global weighted space-time estimates as well as the global existence of small data weak solution u when the nonlinearity power p is larger than some critical power p_(crit)(μ).Our proof is based on a class of new weighted Strichartz estimates with the weight t^(θ)|(1-μ)^(2)t^(2/|1-μ|)-x^(2)|^(γ)(θ>0andγ>0 are appropriate constants)for the solution of linear generalized Tricomi equation∂_(t)^(2)φ-t^(m)∂_(x)^(2)φ=0 with m being any fixed positive number. 展开更多
关键词 critical exponent generalized Tricomi equation scale-invariant damping weighted Strichartz estimate Fourier integral operator global existence
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Personalized folic acid supplementation in pregnant women based on MTHFR and MTRR gene polymorphisms
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作者 Xiaojun Pang qianqian li +1 位作者 Dongwang li Yingjun Zhang 《Journal of Chinese Pharmaceutical Sciences》 2025年第11期1041-1050,共10页
Folic acid(FA)deficiency during pregnancy is a significant risk factor for neural tube defects in infants.Appropriate supplementation with FA has been shown to effectively mitigate the risk of such congenital anomalie... Folic acid(FA)deficiency during pregnancy is a significant risk factor for neural tube defects in infants.Appropriate supplementation with FA has been shown to effectively mitigate the risk of such congenital anomalies.However,genetic polymorphisms related to FA metabolism influence individual variations in FA utilization among pregnant women,highlighting the need for personalized supplementation strategies.This study aimed to explore the impact of genetic variations in FA metabolism-related genes,specifically methylenetetrahydrofolate reductase(MTHFR)and methionine synthase reductase(MTRR),on tailoring FA supplementation during pregnancy.Using fluorescence hybridization sequencing,we analyzed polymorphisms in the MTHFR and MTRR genes among 694 pregnant women,who were divided into an individualized supplementation group and a control group.Pregnancy outcomes were monitored through outpatient visits and telephone follow-ups to evaluate the effect of personalized FA supplementation guided by genetic profiling.Notable differences in genotype frequencies of MTHFR(rs1801133,rs1801131)and MTRR(rs1801394)were observed between pregnant women with and without a heightened risk of FA metabolism disorders(P<0.05).Similarly,allele frequencies of MTHFR(rs1801133)and MTRR(rs1801394)varied significantly among women with different risk profiles(P<0.05).The results demonstrated that the individualized group exhibited significantly lower incidences of birth defects,preterm delivery,spontaneous abortion,premature rupture of membranes,abnormal amniotic fluid,and gestational hypertension compared to the control group(P<0.05).These findings suggested that polymorphisms in MTHFR and MTRR genes were key determinants of FA metabolism and might contribute to adverse pregnancy outcomes in populations with a high prevalence of FA metabolism disorders.Furthermore,integrating genetic screening into FA supplementation protocols enabled more effective prevention of pregnancy complications and improved overall maternal and fetal health outcomes. 展开更多
关键词 Folic acid Gene polymorphism Methylenetetrahydrofolate reductase Methionine synthase reductase Pregnancy outcome
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Electronic interactions between neighboring functionalized vip Sb single atoms and Pt clusters enhance CO tolerance
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作者 Wenkang Miao Ronghui Hao +10 位作者 Lu Gan Wanyin Xu Zihan Wang Wenxin lin Heguang liu Yinchun Lyu qianqian li Jinyang Xi Anmin Nie Jinsong Wu Hongtao Wang 《Journal of Energy Chemistry》 2025年第2期733-743,I0016,共12页
Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing... Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing their catalytic activity,selectivity,and durability remains a major challenge.Herein,we propose a strategy to enhance the CO tolerance of Pt clusters(Pt_n)by introducing neighboring functionalized vip single atoms(such as Fe,Co,Ni,Cu,Sb,and Bi).Among them,antimony(Sb)single atoms(SAs)exhibit significant performance enhancement,achieving 99%CO selectivity and 33.6%CO_(2)conversion at 450℃,Experimental results and density functional theory(DFT)calculations indicate the optimization arises from the electronic interaction between neighboring functionalized Sb SAs and Pt clusters,leading to optimal 5d electron redistribution in Pt clusters compared to other functionalized vip single atoms.The redistribution of 5d electrons weaken both theσdonation andπbackdonation interactions,resulting in a weakened bond strength with CO and enhancing catalyst activity and selectivity.In situ environmental transmission electron microscopy(ETEM)further demonstrates the exception thermal stability of the catalyst,even under H_(2)at 700℃.Notably,the functionalized Sb SAs also improve CO tolerance in various heterogenous catalysts,including Co/CeO_(2),Ni/CeO_(2),Pt/Al_(2)O_(3),and Pt/CeO_(2)-C.This finding provides an effective approach to overcome the primary challenge of CO poisoning in Pt-based catalysts,making their broader applications in various industrial catalysts. 展开更多
关键词 Functionalized vip single atoms Pt cluster CO tolerance Electronic effect In-situ TEM
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Membrane recycling and resource utilization:Latest progress and prospects
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作者 Jiahao li Chaojie Lu +6 位作者 Jingqiu Sun Hui Peng qianqian li Seyed Saeid Hosseini Yuzhang Zhu Meng Sun Baiwen Ma 《Journal of Environmental Sciences》 2025年第10期346-359,共14页
Membrane technology has thus far played an essential role in promoting environmental sustainability through improving the quality of water.Taking into account the current growth rate of membrane products along with th... Membrane technology has thus far played an essential role in promoting environmental sustainability through improving the quality of water.Taking into account the current growth rate of membrane products along with the market capacity,a tremendous rise in the amount of end-of-life(EoL)membranes is inevitable.In 2022,the global records of EoL membranes reached 35,000 tons.Recycling and resource utilization of EoL membranes is a viable option and hold significant promises for energy conservation and carbon neutralization.The present work provides an extensive overview of the latest progress in the field in relation with the prominent application cases.Furthermore,the avenues for the contributions of membrane recycling treatment technology within the framework of“carbon neutrality”are discussed with emphasis on permeability,pollutant interception capacity,and other relevant factors associated with the recycled membranes.This review strives to summarize the recycling and efficient utilization of EoL membranes,aiming at providing technical support to reduce operational costs and promote the low-carbon development of membrane technology. 展开更多
关键词 Carbon neutralization Membrane technology End of life membrane Membrane recycling Resource utilization
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Micellization behavior and thermodynamic properties of cetyltrimethylammonium bromide in lithium chloride,potassium chloride,magnesium chloride and calcium chloride solutions
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作者 Wenting Cheng qianqian li +2 位作者 Ying Zhai Huaigang Cheng Fangqin Cheng 《Chinese Journal of Chemical Engineering》 2025年第5期95-104,共10页
The micellization behavior and thermodynamic properties of cetyltrimethylammonium bromide(CTAB)in single lithium chloride(LiCl),potassium chloride(KCl),magnesium chloride(MgCl_(2))and calcium chloride(CaCl_(2))solutio... The micellization behavior and thermodynamic properties of cetyltrimethylammonium bromide(CTAB)in single lithium chloride(LiCl),potassium chloride(KCl),magnesium chloride(MgCl_(2))and calcium chloride(CaCl_(2))solutions were investigated at 288.15318.15 K.Result showed that the critical micelle concentration(CMC)values of CTAB in all solutions decreased to a minimum value around 298.15 K and then increased with further increasing the temperature.In all cases,the CMC values decreased with increasing salt concentration at each temperature.Additionally,the introduction of any single salt resulted in a reduction of CMC values for CTAB,attributed to the combined effects of counterions and entropy-driven interactions.The observed trend for CMC values was as follows:CMCH_(2)O>CMCKCl>CMCLiCl>CMCCaCl_(2)>CMCMgCl_(2).Furthermore,standard thermodynamic parameters,including standard free energy of micellization(ΔDG_(m)^(0)),standard enthalpy of micellization(ΔDH0m)and standard entropy of micellization(DS0 m),were calculated based on the obtained CMC values.The negative values ofΔDG_(m)^(0)indicated that the formation of CTAB micelles was a spontaneous behavior.The variations inΔDH0m andΔDS_(m)^(0)suggested that micellization was primarily entropy-driven at temperatures between 288.15 and 298.15 K,while it was influenced by both entropy and enthalpy from 298.15 to 318.15 K.Fourier transform infrared spectroscopy(FTIR)and transmission electron microscope(TEM)were employed to further explore the effects of salts on the micellization behavior of CTAB. 展开更多
关键词 SURFACTANTS SOLUTION Thermodynamic properties Micellization behavior
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Using Physical Model Experiments for Hazards Assessment of Rainfall-Induced Debris Landslides 被引量:13
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作者 qianqian li Dong Huang +2 位作者 Shufeng Pei Jianping Qiao Meng Wang 《Journal of Earth Science》 SCIE CAS CSCD 2021年第5期1113-1128,共16页
Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide ... Using physical simulation models, rainfall-induced landslides have been simulated under various rainfall intensities. During these simulations, we have monitored the physical and mechanical behaviors of the landslide over the slip surface at different heights of the model slopes, as well as taking the whole slope to identify its deformation and failure processes. The results show that the rainfall duration corresponding to the initiation of the debris landslide and is exponentially related to rainfall intensity. Corresponding to the three intervals of the rainfall intensity, there are three types of slope failure modes:(1) the small-slump failure at the leading edge of the slope;(2) the block-slump failure but sometimes there are large blocks sliding down;and(3) the bulk failure but sometimes there is the block-slump failure. Based on the total rainfall-lasting time and the associated proportion of failed mass volume, the early warning of debris landslide can be classified into five grades, i.e., red, orange to red, orange, yellow to orange and yellow, which correspond to the five slope failure modes, respectively. 展开更多
关键词 rainfall-induced landslides simulation model experiments failure mode hazards assessment
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pH-Sensitive nanoscale materials as robust drug delivery systems for cancer therapy 被引量:9
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作者 Zhaoqing Shi qianqian li lin Mei 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第6期1345-1356,F0003,共13页
Cancer is one of the diseases that have the highest mortality,which threatens the human health.Chemotherapy functions as the most widely used strategy in clinic to treat cancer,still exists urgent problems,like lackin... Cancer is one of the diseases that have the highest mortality,which threatens the human health.Chemotherapy functions as the most widely used strategy in clinic to treat cancer,still exists urgent problems,like lacking selectivity and causing severe side effects.According to detailed researches on the metabolism,functions and histology of cancer tissues,many different features of cancer are uncovered,like lower pH in microenvironment,abnormal redox level in intracellular compartments and elevated expression level of several enzymes and receptors.Recently,the development of smart nanoparticles that response to tumor specific microenvironment has lighted up hope for selective cancer therapy.Herein,this review mainly focuses on pH-sensitive nano scale materials for anti-cancer drug delivery.We summarized the formation progress of acidic tumor microenvironment,the mechanism of pHresponsive drug delivery system and nanomaterials that responsive to acidic pH in tumor microenvironment. 展开更多
关键词 Cancer therapy Drug delivery systems NANOPARTICLES pH-sensitive material
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Effects of 1-MCP on proline,polyamine,and nitric oxide metabolism in postharvest peach fruit under chilling stress 被引量:7
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作者 Chunlu Qian Zhengjie Ji +8 位作者 Qin Zhu Xiaohua Qi qianqian li Jiandong Yin Jun liu Juan Kan Man Zhang Changhai Jin lixia Xiao 《Horticultural Plant Journal》 SCIE CSCD 2021年第3期188-196,共9页
Peach(Prunus persica Batsch‘Yuhualu’)fruit are sensitive to chilling injury(CI).Proline,polyamine(PA),and nitric oxide(NO)are important small regulators of various metabolic pathways under chilling stress that mitig... Peach(Prunus persica Batsch‘Yuhualu’)fruit are sensitive to chilling injury(CI).Proline,polyamine(PA),and nitric oxide(NO)are important small regulators of various metabolic pathways under chilling stress that mitigate CI.Ethylene is known to promote senescence and CI,while 1-methylcyclopropene(1-MCP)is an antagonist that inhibits the effects of ethylene.However,how1-MCP and ethylene affect proline,PA,and NO levels under chilling stress remains unclear.To address these questions,1-MCP(1μL·L^(−1))and ethylene(1μL·L^(−1))treatments were applied to peach fruit.Fruit were stored at 4°C for 28 d,then moved to 25°C for 3 d immediately after cold storage.Peach fruit exhibited CI symptoms after 7 d of cold storage with enhanced electrolyte leakage and malondialdehyde contents.The 1-MCP treatment significantly(P<0.05)restrained peach CI,and fruit did not exhibit CI symptoms until 14 d of cold storage.Proline and PAs in peach under chilling stress weremostly synthesized from glutamate and arginine,which were catalyzed by1-pyrroline-5-carboxylate synthetase and arginine decarboxylase,respectively.1-MCPtreated fruit exhibited higher proline and PA contents and enhanced chilling tolerance compared to the control,while ethylene-treated fruit had lower proline and PA contents and reduced chilling tolerance.Ethylene-treated fruit,which exhibited more severe CI symptoms compared to the control,had significantly(P<0.05)lower NO contents and NO synthase activities.However,NOmay not be a direct acting factor in 1-MCPinduced chilling tolerance,as 1-MCP-treated fruit had lower NO contents and NO synthase activities compared to the control.In conclusion,proline and PA clearly played direct and important roles in 1-MCP-induced peach chilling tolerance,while NO may not be actively involved. 展开更多
关键词 Peach fruit Chilling injury PROLINE Polyamines Nitric oxide 1-MCP ETHYLENE
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Comparison of labeling methods and time course of traumatic brain injury-induced cell death in mice 被引量:6
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作者 Chengliang Luo Xiping Chen +5 位作者 Hong Ni qianqian li Rui Yang Yuxia Sun Guangyou Zhu Luyang Tao 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第9期706-709,共4页
BACKGROUND:Various molecular mechanisms of cell death following traumatic brain injury have been previously described.However,the time course of cell death remains unclear.TUNEL and Fluoro-Jade B labeling have been w... BACKGROUND:Various molecular mechanisms of cell death following traumatic brain injury have been previously described.However,the time course of cell death remains unclear.TUNEL and Fluoro-Jade B labeling have been widely used to label apoptotic cells and neuronal degeneration.Propidium iodide (PI) functions as a biomarker of cell death in vivo.OBJECTIVE:To explore the role of PI labeling compared to TUNEL and Fluoro-Jade B staining for detecting neural cell death,and to observe time course of traumatic brain injury-induced cell death in mice.DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at the Laboratory of Aging and Nervous Diseases,Soochow University from September 2007 to December 2008.MATERIALS:PI (B1221) was purchased from Sigma,USA.TUNEL kit was purchased from Roche Molecular Biochemicals,USA.Fluoro-Jade B was purchased from Chemicon,USA.METHODS:A total of 70 healthy,male,Kunming mice were randomly assigned to sham-surgery (n = 5) and model (n = 65) groups.Traumatic brain injury was established using the controlled cortical impact method.PI was intraperitoneally injected at 1 hour prior to animal sacrifice.MAIN OUTCOME MEASURES:TUNEL,Fluoro-Jade B,and Pl-positive cells were quantified using a double-labeling method to determine the time course of traumatic brain injury-induced cell death.RESULTS:PI labeled cells in an earlier phase of cell death than TUNEL and Fluoro-Jade B labeling.Pl-positive cells were observed immediately following injury,and the numbers rapidly increased in injured brain areas at 1 hour,peaked at 24-48 hours,and subsequently decreased at 3-21 days post-injury.TUNEL-labeled cells were significantly increased at 12 hours,while Fluoro-Jade B-labeled cells were increased at 6 hours after injury,with cells still visible at 6-48 hours post-injury.Moreover,a greater number of Pl-positive cells were observed compared to TUNEL- and Fluoro-Jade B-labeled cells.CONCLUSION:PI labeling is more sensitive and reliable than TUNEL and Fluoro-Jade B staining for detecting cell death following traumatic brain injury.Moreover,PI labeling can function as a reliable marker to estimate the entire time course of cell death. 展开更多
关键词 propidium iodide cell death traumatic brain injury neural regeneration
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Layered manganese phosphorus trisulfides for high-performance lithium-ion batteries and the storage mechanism 被引量:3
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作者 Hailin Shen Yueling Cai +8 位作者 Zhongtao Ma Peng Wang Bingkun Guo Jipeng Cheng qianqian li Hongtao Wang Zhongyuan liu Anmin Nie Jinsong Wu 《Carbon Energy》 SCIE CSCD 2023年第3期160-169,170,171,共12页
Although advanced anode materials for the lithium-ion battery have been investigated for decades,a reliable,high-capacity,and durable material that can enable a fast charge remains elusive.Herein,we report that a meta... Although advanced anode materials for the lithium-ion battery have been investigated for decades,a reliable,high-capacity,and durable material that can enable a fast charge remains elusive.Herein,we report that a metal phosphorous trichalcogenide of MnPS_(3)(manganese phosphorus trisulfide),endowed with a unique and layered van der Waals structure,is highly beneficial for the fast insertion/extraction of alkali metal ions and can facilitate changes in the buffer volume during cycles with robust structural stability.The few-layered MnPS_(3)anodes displayed the desirable specific capacity and excellent rate chargeability owing to their good electronic and ionic conductivities.When assembled as a half-cell lithium-ion battery,a high reversible capacity of 380 mA h g^(−1)was maintained by the MnPS_(3)after 3000 cycles at a high current density of 4 A g^(−1),with a capacity retention of close to or above 100%.In full-cell testing,a reversible capacity of 450 mA h g^(−1)after 200 cycles was maintained as well.The results of in-situ TEM revealed that MnPS_(3)nanoflakes maintained a high structural integrity without exhibiting any pulverization after undergoing large volumetric expansion for the insertion of a large number of lithium ions.Their kinetics of lithium-ion diffusion,stable structure,and high pseudocapacitance contributed to their comprehensive performance,for example,a high specific capacity,rapid charge-discharge,and long cyclability.MnPS_(3)is thus an efficient anode for the next generation of batteries with a fast charge/discharge capability. 展开更多
关键词 cyclic stability in‐situ TEM MnPS3 PSEUDOCAPACITANCE rate performance
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A Data-Semantic-Conflict-Based Multi-Truth Discovery Algorithm for a Programming Site 被引量:2
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作者 Haitao Xu Haiwang Zhang +2 位作者 qianqian li Tao Qin Zhen Zhang 《Computers, Materials & Continua》 SCIE EI 2021年第8期2681-2691,共11页
With the extensive application of software collaborative development technology,the processing of code data generated in programming scenes has become a research hotspot.In the collaborative programming process,differ... With the extensive application of software collaborative development technology,the processing of code data generated in programming scenes has become a research hotspot.In the collaborative programming process,different users can submit code in a distributed way.The consistency of code grammar can be achieved by syntax constraints.However,when different users work on the same code in semantic development programming practices,the development factors of different users will inevitably lead to the problem of data semantic conflict.In this paper,the characteristics of code segment data in a programming scene are considered.The code sequence can be obtained by disassembling the code segment using lexical analysis technology.Combined with a traditional solution of a data conflict problem,the code sequence can be taken as the declared value object in the data conflict resolution problem.Through the similarity analysis of code sequence objects,the concept of the deviation degree between the declared value object and the truth value object is proposed.A multi-truth discovery algorithm,called the multiple truth discovery algorithm based on deviation(MTDD),is proposed.The basic methods,such as Conflict Resolution on Heterogeneous Data,Voting-K,and MTRuths_Greedy,are compared to verify the performance and precision of the proposed MTDD algorithm. 展开更多
关键词 Data semantic conflict multi-truth discovery programming site
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Dynamic Resource Pricing and Allocation in Multilayer Satellite Network 被引量:1
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作者 Yuan li Jiaxuan Xie +4 位作者 Mu Xia qianqian li Meng li Lei Guo Zhen Zhang 《Computers, Materials & Continua》 SCIE EI 2021年第12期3619-3628,共10页
The goal of delivering high-quality service has spurred research of 6G satellite communication networks.The limited resource-allocation problem has been addressed by next-generation satellite communication networks,es... The goal of delivering high-quality service has spurred research of 6G satellite communication networks.The limited resource-allocation problem has been addressed by next-generation satellite communication networks,especially multilayer networks with multiple low-Earth-orbit(LEO)and nonlow-Earth-orbit(NLEO)satellites.In this study,the resource-allocation problem of a multilayer satellite network consisting of one NLEO and multiple LEO satellites is solved.The NLEO satellite is the authorized user of spectrum resources and the LEO satellites are unauthorized users.The resource allocation and dynamic pricing problems are combined,and a dynamic gamebased resource pricing and allocation model is proposed to maximize the market advantage of LEO satellites and reduce interference between LEO and NLEO satellites.In the proposed model,the resource price is formulated as the dynamic state of the LEO satellites,using the resource allocation strategy as the control variable.Based on the proposed dynamic game model,an openloop Nash equilibrium is analyzed,and an algorithm is proposed for the resource pricing and allocation problem.Numerical simulations validate the model and algorithm. 展开更多
关键词 Resource pricing resource allocation satellite network LEO dynamic game Nash equilibrium
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Icosahedral quasicrystal structure of the Mg_(40)Zn_(55)Nd_(5) phase and its thermodynamic stability 被引量:1
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作者 Shuai Zhang qianqian li +2 位作者 Hongcan Chen Qun Luo Qian li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第8期1543-1550,共8页
The quasicrystal phase is beneficial to increasing the strength of magnesium alloys.However,its complicated structure and unclear phase relations impede the design of alloys with good mechanical properties.In this pap... The quasicrystal phase is beneficial to increasing the strength of magnesium alloys.However,its complicated structure and unclear phase relations impede the design of alloys with good mechanical properties.In this paper,the Mg_(40)Zn_(55)Nd_(5) icosahedral quasicrystal(I-phase)structure is discovered in an as-cast Mg-58Zn-4Nd alloy by atomic resolution high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM).A cloud-like morphology is observed with Mg_(41.6)Zn_(55.0)Nd_(3.4) composition.The selected area electronic diffrac-tion(SAED)analysis shows that the icosahedral quasicrystal structure has 5-fold,4-fold,3-fold,and 2-fold symmetry zone axes.The thermo-dynamic stability of the icosahedral quasicrystal is investigated by differential scanning calorimetry(DSC)in the annealed alloys.When an-nealed above 300℃,the Mg_(40)Zn_(55)Nd_(5) quasicrystal is found to decompose into a stable ternary phase Mg_(35)Zn_(60)Nd_(5),a binary phase MgZn,andα-Mg,suggesting that the quasicrystal is a metastable phase in the Mg-Zn-Nd system. 展开更多
关键词 icosahedral quasicrystal crystal structure thermodynamic stability Mg-Zn-Nd alloys
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Random Forests Algorithm Based Duplicate Detection in On-Site Programming Big Data Environment 被引量:1
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作者 qianqian li Meng li +1 位作者 Lei Guo Zhen Zhang 《Journal of Information Hiding and Privacy Protection》 2020年第4期199-205,共7页
On-site programming big data refers to the massive data generated in the process of software development with the characteristics of real-time,complexity and high-difficulty for processing.Therefore,data cleaning is e... On-site programming big data refers to the massive data generated in the process of software development with the characteristics of real-time,complexity and high-difficulty for processing.Therefore,data cleaning is essential for on-site programming big data.Duplicate data detection is an important step in data cleaning,which can save storage resources and enhance data consistency.Due to the insufficiency in traditional Sorted Neighborhood Method(SNM)and the difficulty of high-dimensional data detection,an optimized algorithm based on random forests with the dynamic and adaptive window size is proposed.The efficiency of the algorithm can be elevated by improving the method of the key-selection,reducing dimension of data set and using an adaptive variable size sliding window.Experimental results show that the improved SNM algorithm exhibits better performance and achieve higher accuracy. 展开更多
关键词 On-site programming big data duplicate record detection random forests adaptive sliding window
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Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China
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作者 Xu Zhao Jing Meng +5 位作者 qianqian li Guijin Su Qifan Zhang Bin Shi lingwen Dai Yong Yu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期651-663,共13页
Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing pollution.However,in the process,seasonal effect on contamination... Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing pollution.However,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often neglected.Herein,Yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for traceability.Season variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle phase.Source profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors determination.Contributions of the five zones were 14.9%,20.8%,13.6%,22.1%,and 28.6%in winter and 33.4%,12.5%,10.7%,24.9%,and 18.5%in spring,respectively.The variation in the soil sorption capacity of VOCs causes inter-seasonal differences in contribution.The better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to spring.This study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites. 展开更多
关键词 Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile
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Unraveling the reaction reversibility and structure stability of nickel sulfide anodes for lithium ion batteries
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作者 Yu Huang Chunyuan liang +10 位作者 Yueling Cai Yi Zhou Bingkun Guo Jipeng Cheng Heguang liu Peng Wang qianqian li Anmin Nie Hongtao Wang Jinsong Wu Tongyi Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期392-401,I0010,共11页
The electrochemical performance of lithium-ion batteries,i.e.specific capacity and cyclability,is primarily determined by chemical reversibility and structural stability of the electrodes in cycling.Here we have inves... The electrochemical performance of lithium-ion batteries,i.e.specific capacity and cyclability,is primarily determined by chemical reversibility and structural stability of the electrodes in cycling.Here we have investigated the fundamental reaction behaviors of nickel sulfide(NixSy)as lithium-ion battery anodes by in-situ TEM.We find that Ni_(3)S_(2)is the electrochemically stable phase,which appears in the first cycle of the NixSyanode.From the second cycle,conversion between Ni_(3)S_(2)and Li_(2)S/Ni is the dominant electrochemical reaction.In lithiation,the NixSynanoparticles evolve into a mixture of Ni nanocrystals embedded in Li_(2)S matrix,which form a porous structure upon full lithiation,and with the recrystallization of the Ni_(3)S_(2)phase in delithiation,a compact and interconnected network is built.Structural stability in cycles is susceptible to particle size and substrate restraint.Carbon substrate can certainly improve the tolerance for size-dependent pulverization of NixSynanoparticles.When NixSynanoparticle exceeds the critical size value,the morphology of the particle is no longer well maintained even under the constraints of the carbon substrate.This work deepens the understanding of electrochemical reaction behavior of conversiontype materials and helps to rational design of high-energy density battery anodes. 展开更多
关键词 Nickel sulfide anodes Reaction reversility Structure rebuilding In-situ TEM Lithium-ion battery
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Efficient CO_2/N_2 separation by mixed matrix membrane with amide functionalized porous coordination polymer filler
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作者 qianqian li Jingui Duan Wanqin Jin 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第6期854-856,共3页
Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination... Mixed matrix membrane used to selective removal of CO2 was considered as an efficient solution to energy and environmental sustainability. In this study, a MMM that consists of amide functionalized porous coordination polymer filler(MIL-53-NH2) was successfully prepared, which sharply promotes the CO2/N2 selectivity from 44(neat polymeric membrane) to 75. Remarkably, the positive effect of amide group and nanochannel of MIL-53-NH2 filler was illustrated by decreased selectivity of the MMM with formic acid modified MIL-53-NH2 filler(MIL-53-NHCOH). 展开更多
关键词 Porous coordination polymer Mixed matrix membrane CO2/N2 separation Amide group
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Genome-Wide Characterization of the Cellulose Synthase Gene Superfamily in Tea Plants(Camellia sinensis)
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作者 qianqian li Qi Zhao +2 位作者 Xinzhuan Yao Baohui Zhang litang Lu 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第10期2163-2189,共27页
The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes... The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes are vital for abiotic stress resistance and shoot tenderness regulation of tea plants(Camellia sinensis).However,the CesA/Csl gene family has not been extensively studied in tea plants.Here,we identified 53 CsCesA/Csl genes in tea plants.These genes were grouped into five subfamilies(CsCesA,CsCslB,CsCslD,CsCslE,CsCslG)based on the phylogenetic relationships with Arabidopsis and rice.The analysis of chromosome distribution,gene structure,protein domain and motif revealed that most genes in CsCesA,CsCslD and CsCslE subfamilies were conserved,whereas CsCslB and CsCslG subfamily members are highly diverged.The transcriptome analysis showed that most CsCesA/Csl genes displayed tissue-specific expression pattern.In addition,members of CsCslB4,CsCesA1/3/6,CsCslB3/4,CsCslD3,CsCslE1 and CsCslG2/3 subfamilies were up-regulated under drought and cold stresses,indicating their potential roles in regulating stress tolerance in tea plants.Furthermore,the expression levels of CsCslG2_6 and CsCslD3_5 in different tissues and cultivars,respectively,were positively correlated with the cellulose content that is negatively related with shoot tenderness.Thus,these two genes were speculated to be involved in the regulation of shoot tenderness in tea plants.Our findings may help elucidate the evolutionary relationships and expression patterns of the CsCesA/Csl genes in tea plants,and provide more candidate genes responsible for stress tolerance and tenderness regulation in tea plants for future functional research. 展开更多
关键词 Tea plant(Camellia sinensis) cellulose synthase superfamily PHYLOGENY stress resistance shoot tenderness regulation
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Effective stress dissipation by multi-dimensional architecture engineering for ultrafast and ultralong sodium storage
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作者 Man Zhang Jing Zhu +7 位作者 qianqian li Fenghua Zheng Sijiang Hu Youguo Huang Hongqiang Wang Xing Ou Qichang Pan Qingyu li 《Journal of Energy Chemistry》 2025年第2期619-629,I0013,共12页
Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial... Stress accumulation is a key factor leading to sodium storage performance deterioration for NiSe_(2)-based anodes.Therefore,inhibiting the concentrated local stress during the sodiataion/desodiation process is crucial for acquiring stable NiSe2-based materials for sodium-ion batteries(SIBs),Herein,a stress dissipation strategy driven by architecture engineering is proposed,which can achieve ultrafast and ultralong sodium storage properties.Different from the conventional sphere-like or rod-like architecture,the three-dimensional(3D)flower-like NiSe_(2)@C composite is delicately designed and assembled with onedimensional nanorods and carbon framework.More importantly,the fundamental mechanism of improved structure stability is unveiled by simulations and experimental results simultaneously.It demonstrates that this designed multidimensional flower-like architecture with dispersed nanorods can balance the structural mismatch,avoid concentrated local strain,and relax the internal stress,mainly induced by the unavoidable volume variation during the repeated conversion processes.Moreover,it can provide more Na^(+)-storage sites and multi-directional migration pathways,leading to a fast Na^(+)-migration channel with boosted reaction kinetic.As expected,it delivers superior rate performance(441 mA h g^(-1)at 5.0 A g^(-1))and long cycling stability(563 mA h g^(-1)at 1.0 A g^(-1)over 1000 cycles)for SIBs.This work provides useful insights for designing high-performance conversion-based anode materials for SIBs. 展开更多
关键词 Stress dissipation Multi-dimensional architecture Structure engineering Conversion-based anodes Sodium-ion batteries
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Some new viewpoints revealed by the phylogeny of Blaberidae(Blattaria)based on seven gene fragment markers
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作者 Jiawei ZHANG Zengzeng SHI +4 位作者 Xiudan WANG Wenwen YAO qianqian li Yanli CHE Zongqing WANG 《Entomotaxonomia》 2025年第4期320-338,共19页
Despite consistent support from previous studies for the monophyly of the Blaberidae family,the phylogenetic relationship among its subfamilies remain unresolved.To establish a robust phylogenetic framework for Blaber... Despite consistent support from previous studies for the monophyly of the Blaberidae family,the phylogenetic relationship among its subfamilies remain unresolved.To establish a robust phylogenetic framework for Blaberidae,we analyzed 139 blaberid taxa(including the rarely sampled genus Rhabdoblattella)and 35 outgroup taxa based on seven gene fragments,using maximum likelihood(ML)and Bayesian inference(BI)methods.The results indicate that,after excluding Epilampra taira and Galiblatta cribrosa,the Epilamprinae is monophyletic and sistergroup to Calolamprodes beybienkoi.Panesthinae and Geoscapheinae together form a monophyletic group,but Panesthia and four genera within Geoscapheinae(Neogeoscapheus,Parapanesthia,Geoscapheus and Macropanesthia)are polyphyletic.Our phylogenetic analyses support the establishment of the subfamilies Rhabdoblattellinae and Calolamprodinae,as well as the classification of Geoscapheinae as a synonym under Panesthinae,and propose that the four genera within Geoscapheinae should be synonymized with Panesthia.Furthermore,based on phylogenetic evidence and similarities in the right phallomere(the R2 moderately rounded,R3 fused with R5,enlarged caudally),we transfer Rhabdoblatta monticola to the genus Opisthoplatia. 展开更多
关键词 Epilamprinae Panesthiinae Geoscapheinae Rhabdoblattella SYNONYM
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