期刊文献+
共找到119,972篇文章
< 1 2 250 >
每页显示 20 50 100
Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
1
作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
在线阅读 下载PDF
Existence,Uniqueness and Stability of Bounded Solutions for Minkowski-Curvature Problems with Asymptotic Boundary Conditions
2
作者 Tianlan CHEN Xuying TANG 《Journal of Mathematical Research with Applications》 2026年第1期57-70,共14页
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→... In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions. 展开更多
关键词 mean curvature operator UNIQUENESS asymptotic boundary conditions bounded solution
原文传递
SNA、MPS核算的经济学基础与实体经济“去工业化”趋势——加密资产纳入SNA(2025)核算的思考
3
作者 刘晓欣 《山东财经大学学报》 2025年第6期5-33,共29页
国民经济核算体系是经济学和统计学的相互促进与共同发展所形成的。20世纪50年代以来,国民经济账户体系(SNA)核算的GDP成为全球判断经济增长、制定宏观政策的核心指标,但由GDP作为唯一引导目标反映的经济繁荣却模糊了经济增长与风险积... 国民经济核算体系是经济学和统计学的相互促进与共同发展所形成的。20世纪50年代以来,国民经济账户体系(SNA)核算的GDP成为全球判断经济增长、制定宏观政策的核心指标,但由GDP作为唯一引导目标反映的经济繁荣却模糊了经济增长与风险积聚界线,导致世界经济“去工业化”和“虚拟化”。随着加密资产纳入SNA(2025)核算体系的全球推广,世界经济“脱实向虚”趋势将越加严重。认识市场经济本质、财富属性与产业高端化的误区,揭示以金融房地产为核心的虚拟经济创造GDP的机制,准确预警金融危机爆发成为重要议题。通过梳理SNA与MPS两种核算体系背后的理论逻辑,运用马克思生产劳动理论对GDP核算进行反思,揭示将比特币、稳定币等加密资产纳入SNA(2025)核算的现实背景与风险隐患,利用SNA与MPS体系总量指标逆转换模型,注重MPS的核算理念,构建实体经济发展规模新指标体系,测度分析全球30个国家经济“去工业化”演变特征和运行规律。试图为监测经济稳定发展和风险防范提供新思路和新方法,为构建经济学和统计学自主知识体系提供参考。 展开更多
关键词 金融GDP核算 加密资产 虚拟经济 去工业化 SNA与mps逆转换模型
在线阅读 下载PDF
ON SOLUTIONS OF BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS WITH JUMPS,WITH UNBOUNDED STOPPING TIMES AS TERMINAL AND WITH NON-LIPSCHITZ COEFFICIENTS,AND PROBABILISTIC INTERPRETATION OF QUASI-LINEAR ELLIPTIC TYPE INTEGRO-DIFFERENTIAL EQUATIO 被引量:1
4
作者 司徒荣 王越平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第6期659-672,共14页
The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non_Lipschitz condition are obtained. The convergence of soluti... The existence and uniqueness of solutions to backward stochastic differential equations with jumps and with unbounded stopping time as terminal under the non_Lipschitz condition are obtained. The convergence of solutions and the continuous dependence of solutions on parameters are also derived. Then the probabilistic interpretation of solutions to some kinds of quasi_linear elliptic type integro_differential equations is obtained. 展开更多
关键词 backward stochastic differential equations(BSDEs) with jumps unbounded stopping time adapted solutions convergence of solutions quasi_linear elliptic equations integro_differential operators.
在线阅读 下载PDF
REFLECTED BACKWARD STOCHASTIC DIFFERENTIAL EQUATION WITH JUMPS AND VISCOSITY SOLUTION OF SECOND ORDER INTEGRO-DIFFERENTIAL EQUATION WITHOUT MONOTONICITY CONDITION: CASE WITH THE MEASURE OF LéVY INFINITE 被引量:1
5
作者 Lamine SYLLA 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期819-844,共26页
We consider the problem of viscosity solution of integro-partial differential equation( IPDE in short) with one obstacle via the solution of reflected backward stochastic dif ferential equations(RBSDE in short) with j... We consider the problem of viscosity solution of integro-partial differential equation( IPDE in short) with one obstacle via the solution of reflected backward stochastic dif ferential equations(RBSDE in short) with jumps. We show the existence and uniqueness of a continuous viscosity solution of equation with non local terms, if the generator is not monotonous and Levy's measure is infinite. 展开更多
关键词 Integro-partial DIFFERENTIAL equation reflected stochastic DIFFERENTIAL equations with JUmps viscosity solution NON-LOCAL operator
在线阅读 下载PDF
General M-lumps, T-breathers, and hybrid solutions to (2+1)-dimensional generalized KDKK equation 被引量:1
6
作者 Peisen Yuan Jiaxin Qi +1 位作者 Ziliang Li Hongli An 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期173-183,共11页
A special transformation is introduced and thereby leads to the N-soliton solution of the(2+1)-dimensional generalized Konopelchenko-Dubrovsky-Kaup-Kupershmidt(KDKK) equation.Then,by employing the long wave limit and ... A special transformation is introduced and thereby leads to the N-soliton solution of the(2+1)-dimensional generalized Konopelchenko-Dubrovsky-Kaup-Kupershmidt(KDKK) equation.Then,by employing the long wave limit and imposing complex conjugate constraints to the related solitons,various localized interaction solutions are constructed,including the general M-lumps,T-breathers,and hybrid wave solutions.Dynamical behaviors of these solutions are investigated analytically and graphically.The solutions obtained are very helpful in studying the interaction phenomena of nonlinear localized waves.Therefore,we hope these results can provide some theoretical guidance to the experts in oceanography,atmospheric science,and weather forecasting. 展开更多
关键词 KDKK equation Hirota bilinear method high-order lump solution T-breather solution hybrid solution
原文传递
Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy 被引量:1
7
作者 Xin Zhou Dan Ma +7 位作者 Yi-Xiang He Jing Jin Hong-Lian Wang Yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期110-125,共16页
BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.... BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after ESD.AIM To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus post-ESD.METHODS Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential ESD.Endoscopic examinations occurred on days 7 and 21 post-ESD.In vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was assessed.Profibrotic signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after ESD.After treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal layer.Additionally,the expression of fibrotic effector molecules was notably inhibited.Mechanistically,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/3.In vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen I.The 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated pEsF.CONCLUSION KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway. 展开更多
关键词 Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis
暂未订购
Ascorbic acid-induced porous iodide layer for a high-purity two-step solution-processed tin-lead mixed perovskite photodetector 被引量:2
8
作者 Liansong Liu Fengren Cao +3 位作者 Liukang Bian Meng Wang Haoxuan Sun Liang Li 《Journal of Materials Science & Technology》 2025年第7期227-232,共6页
Tin(Sn)-lead(Pb)mixed halide perovskites have attracted widespread interest due to their wider re-sponse wavelength and lower toxicity than lead halide perovskites,Among the preparation methods,the two-step method mor... Tin(Sn)-lead(Pb)mixed halide perovskites have attracted widespread interest due to their wider re-sponse wavelength and lower toxicity than lead halide perovskites,Among the preparation methods,the two-step method more easily controls the crystallization rate and is suitable for preparing large-area per-ovskite devices.However,the residual low-conductivity iodide layer in the two-step method can affect carrier transport and device stability,and the different crystallization rates of Sn-and Pb-based per-ovskites may result in poor film quality.Therefore,Sn-Pb mixed perovskites are mainly prepared by a one-step method.Herein,a MAPb_(0.5)Sn_(0.5)I_(3)-based self-powered photodetector without a hole transport layer is fabricated by a two-step method.By adjusting the concentration of the ascorbic acid(AA)addi-tive,the final perovskite film exhibited a pure phase without residues,and the optimal device exhibited a high responsivity(0.276 A W^(-1)),large specific detectivity(2.38×10^(12) Jones),and enhanced stability.This enhancement is mainly attributed to the inhibition of Sn2+oxidation,the control of crystal growth,and the sufficient reaction between organic ammonium salts and bottom halides due to the AA-induced pore structure. 展开更多
关键词 PEROVSKITE SN-PB PHOTODETECTOR Two-step solution method
原文传递
Colorectal cancer early screening:Dilemmas and solutions 被引量:2
9
作者 Di Wu Qi-Ying Song +4 位作者 Bai-Shu Dai Jie Li Xin-Xin Wang Jia-Yu Liu Tian-Yu Xie 《World Journal of Gastroenterology》 2025年第9期154-160,共7页
Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhan... Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhancing patient prognosis.Obviously,non-participation of asymptomatic individuals in screening programs hampers early diagnosis and may adversely affect long-term outcomes for CRC patients.In this letter,we provide a comprehensive overview of the current status of early screening practices,while also thoroughly examine the dilemmas and potential solutions associated with early screening for CRC.In response to these issues,we proffer a set of recommendations directed at governmental authorities and the general public,which focus on augmenting financial investment,establishing standardized screening protocols,advancing technological capabilities,and bolstering public awareness campaigns.The importance of collaborative efforts from various stakeholders cannot be overstated in the quest to enhance early detection rates and alleviate the societal burden of CRC. 展开更多
关键词 Colorectal cancer Early screening Asymptomatic candidates DILEMMAS solutionS
暂未订购
Features and classification of solid solution behavior of ternary Mg alloys 被引量:1
10
作者 Tao Chen Yuan Yuan +6 位作者 Jun Wang Jiajia Wu Bin Wang Xianhua Chen Nele Moelans Jingfeng Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第6期2522-2539,共18页
The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg al... The performance of Mg alloys is significantly influenced by the concentrations and solid solution behavior of the alloying elements.In this work,the solid solution behavior of 20 alloying elements in 190 ternary Mg alloy systems at 500℃are systematically investigated.The solid solution behavior of a set of two different alloying elements in Mg alloy systems are suggested to be classified into three categories:inclusivity,exclusivity and proportionality.Inclusivity classification indicates that the two alloying elements are inclusive inα-Mg,increasing the joint solubility of both elements.Exclusivity classification suggests that the two alloying elements have a low joint solid solubility inα-Mg,since they prefer to form stable second phases.For the proportionality classification,the solubility curve of the ternary Mg alloy systems is a straight line connecting the solubility points of the two sub-binary systems.The proposed classification theory was validated by key experiments and the calculation of formation energies.The interaction effects between alloying elements and the preference of formation of second phases are the main factors determining the solid solution behavior classifications.Based on the observed solid solution features of multi-component Mg alloys,principles for alloy design of different types of high-performance Mg alloys were proposed in this work. 展开更多
关键词 Mg alloys solution behavior Phase diagram Alloy design
在线阅读 下载PDF
Fluid therapy in acute pancreatitis comparing balanced solutions and normal saline:A systematic review,meta-analysis and trial sequential analysis 被引量:1
11
作者 Lin Gao Hsiang-Wei Wang +4 位作者 Zi-Rui Liu Yi-Zhen Xu Lu Ke Wei-Qin Li John A Windsor 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期371-380,共10页
Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the t... Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the type of fluid are conflicting and generally come from small single-center randomized controlled trials(RCTs).We therefore conducted a systematic review and meta-analysis to compare the effect of balanced solutions(BS)versus NS on patient-centered clinical outcomes in AP.Methods:From four databases searched up to October 2024,we included only RCTs of adult patients with AP that compared the use of BS(including LR,acetate Ringer’s,etc.)with NS.The primary out-come was the disease advances from AP to moderately severe and severe AP(MSAP/SAP).Trial sequential analyses(TSA)were conducted to control for type-I and type-II errors and Grading of Recommendations Assessment,Development,and Evaluation(GRADE)was used to assess the quality of evidence.Results:Six RCTs were identified and included,involving 260 patients treated with BS and 298 patients with NS.Patients who received the BS had less MSAP/SAP[odds ratio(OR)=0.50,95%confidence in-terval(CI):0.29 to 0.85,P=0.01,I^(2)=0%;5 studies,299 patients],reduced the need of ICU admission(OR=0.60,95%CI:0.39 to 0.93,P=0.02,I^(2)=0%;5 studies,507 patients)and shorter length of hospital stay[mean difference(MD)=-0.88,95%CI:-1.48 to-0.28,P=0.004,I^(2)=0%;6 studies,558 patients;confirmed by TSA with high certainty]compared with those who received NS.The evidence for most of the clinical outcomes was rated as moderate to low due to the risk of bias,imprecision and inconsistency.Conclusions:BS,compared with NS,was associated with improved clinical outcomes in patients with AP.However,given the moderate to low quality of evidence for most of the outcomes assessed,further trials are warranted. 展开更多
关键词 Acute pancreatitis Fluid therapy Normal saline Balanced solution Systematic review
暂未订购
V–Ti‑Based Solid Solution Alloys for Solid‑State Hydrogen Storage 被引量:2
12
作者 Shaoyang Shen Yongan Li +3 位作者 Liuzhang Ouyang Lan Zhang Min Zhu Zongwen Liu 《Nano-Micro Letters》 2025年第7期453-482,共30页
This review details the advancement in the development of V–Ti-based hydrogen storage materials for using in metal hydride(MH)tanks to supply hydrogen to fuel cells at relatively ambient temperatures and pressures.V... This review details the advancement in the development of V–Ti-based hydrogen storage materials for using in metal hydride(MH)tanks to supply hydrogen to fuel cells at relatively ambient temperatures and pressures.V–Tibased solid solution alloys are excellent hydrogen storage materials among many metal hydrides due to their high reversible hydrogen storage capacity which is over 2 wt%at ambient temperature.The preparation methods,structure characteristics,improvement methods of hydrogen storage performance,and attenuation mechanism are systematically summarized and discussed.The relationships between hydrogen storage properties and alloy compositions as well as phase structures are discussed emphatically.For large-scale applications on MH tanks,it is necessary to develop low-cost and high-performance V–Ti-based solid solution alloys with high reversible hydrogen storage capacity,good cyclic durability,and excellent activation performance. 展开更多
关键词 Hydrogen storage V-Ti-based solid solution alloys Metal hydride tank Hydrogen storage properties Cyclic stability
在线阅读 下载PDF
Methods for Exact Solutions of Nonlinear Ordinary Differential Equations
13
作者 Robert CONTE Micheline MUSETTE +1 位作者 Tuen Wai NG WU Chengfa 《数学进展》 北大核心 2025年第2期379-389,共11页
In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic... In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic solutions of some nonlinear ODEs together with some classical,19th-century results,can be turned into algorithms(thus avoiding ad hoc assumptions)which provide all(as opposed to some)solutions in a precise class.To illustrate these methods,we present some new such exact solutions,physically relevant. 展开更多
关键词 elliptic solution complex Ginzburg-Landau equation Closed-form solution Nevanlinna theory
原文传递
Progress in study of spray pyrolysis technology for chloride salt solutions in rare earth extraction and separation processes 被引量:1
14
作者 Ziyi Cheng Xiaowei Huang +5 位作者 Zongyu Feng Jianping Long Hai Yu Meng Wang Juanyu Yang Haiqing Hao 《Journal of Rare Earths》 2025年第10期2053-2064,I0001,共13页
This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.... This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.It proposes the idea of introducing spray pyrolysis technology into the rare earth extraction and separation processes.This paper briefly describes the development history of chloride spray pyrolysis technology,focusing on the research status and application progress of rare earth chloride solution and magnesium chloride solution spray pyrolysis technology,as well as spray pyrolysis equipment.The paper also analyzes the challenges and technical intricacies associated with applying spray pyrolysis technology to chloride solutions in the rare earth extraction and separation processes.Additionally,it explores future trends and proposes strategies to facilitate the full recycling of acids and bases,streamline the process flow,and enhance the prospects for green and low-carbon rare earth metallurgy. 展开更多
关键词 Rare earths Separation processes Spray pyrolysis technology Chloride salt solutions Green recycling
原文传递
Investigation of the formation processes of CO_(2) hydrate films on the interface of liquid carbon dioxide with humic acids solutions 被引量:1
15
作者 Aleksey K.Sagidullin Sergey S.Skiba +1 位作者 Tatyana P.Adamova Andrey Y.Manakov 《Chinese Journal of Chemical Engineering》 2025年第3期53-61,共9页
Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte... Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle. 展开更多
关键词 HYDRATES Carbon dioxide Humic acids solutions Reaction kinetics Liquid liquid reaction Film growth
在线阅读 下载PDF
Peaked traveling wave solutions of the modified highly nonlinear Novikov equation 被引量:1
16
作者 LI Hui-jun WEN Zhen-shu LI Shao-yong 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期375-394,共20页
In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system w... In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system with three singular straight lines,and derive all possible phase portraits under corresponding parameter conditions.Then we show the existence and dynamics of two types of peaked traveling wave solutions including peakons and periodic cusp wave solutions.The exact explicit expressions of two peakons are given.Besides,we also derive smooth solitary wave solutions,periodic wave solutions,compacton solutions,and kink-like(antikink-like)solutions.Numerical simulations are further performed to verify the correctness of the results.Most importantly,peakons and periodic cusp wave solutions are newly found for the equation,which extends the previous results. 展开更多
关键词 modified highly nonlinear Novikov equation bifurcation dynamics peakons periodic cusp wave solutions
在线阅读 下载PDF
Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
17
作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method Normalized solution
在线阅读 下载PDF
Solution loss behavior of cokes and its kinetics under hydrogen-enriched atmosphere
18
作者 YAN Jingchong MA Kaixiang +6 位作者 GE Rong LEI Zhiping LI Zhanku ZHANG Weidong REN Shibiao WANG Zhicai SHUI Hengfu 《燃料化学学报(中英文)》 北大核心 2025年第7期1123-1136,共14页
Hydrogen-enriched ironmaking presents a promising approach to mitigate coke consumption and carbon emission in blast furnace(BF)operations.This work investigated the relationship between the structural features of cok... Hydrogen-enriched ironmaking presents a promising approach to mitigate coke consumption and carbon emission in blast furnace(BF)operations.This work investigated the relationship between the structural features of cokes and their reactivity towards solution loss(SL),especially under hydrogen-enriched atmospheres.Six cokes were characterized,and their SL behaviors were examined under varying atmospheres to elucidate the effects of hydrogen enrichment.The results indicate that an increase in fixed carbon content leads to a decrease in the coke reactivity index(CRI)and an increase in coke strength after reaction(CSR),in the CO_(2) atmosphere,the CSR of coke increases from 35.76%−62.83%,while in the 90CO_(2)/10H_(2) atmosphere,the CSR of coke increases from 65.67%−84.09%.There is a good linear relationship between CRI and microcrystalline structure parameters of coke.Cokes with larger crystalline size,lower amorphous content,and smaller optical texture index(OTI)values show enhanced resistance to degradation and maintain structural integrity in BF.Kinetic analysis performed with the shifted-modified-random pore model(S-MRPM)reveals that alterations in pore structure and intrinsic mineral composition significantly influence the reaction rate.The introduction of a small amount of water vapor raises SL rates,whereas a minor addition of hydrogen(<10%)decelerates SL due to its incomplete conversion to water vapor and the reduced partial pressure of the gasifying agent.Thermodynamic calculations also indicate that the introduced hydrogen does not convert into the same fraction of water vapor.The shift from chemical reaction control to gas diffusion control as the rate-determining step with rising temperatures during SL process was confirmed,and the introduction of hydrogen does not notably alter SL behavior.This result demonstrated that introducing a small amount of hydrogen(<10%)can mitigate SL rates,thereby enhancing coke strength and reducing coke consumption and carbon emissions. 展开更多
关键词 hydrogen-enrichment cokes solution loss KINETICS activation energy
在线阅读 下载PDF
Periodic Solutions for a Stochastic Stage-structure Predator-prey Model with Impulses
19
作者 HOU Meiting QIU Xiaoling 《数学进展》 北大核心 2025年第6期1307-1318,共12页
A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positi... A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positive solution.Second,by selecting an appropriate Lyapunov function,we provide the sufficient condition for the existence of a positive T-periodic solution.Finally,numerical simulations illustrate our theoretical results,which show that the impulse or the white noises can result in the extinction of the predator in a certain condition. 展开更多
关键词 periodic solution stochastic noise IMPULSE
原文传递
Stochastic Periodic Solutions for Two Populations Game Models with Impulses
20
作者 HOU Meiting QIU Xiaoling 《应用数学》 北大核心 2025年第2期453-467,共15页
The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding sto... The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding stochastic and impulse. For the stochastic model without impulses, the existence and uniqueness of solution, and the existence of positive periodic solutions are proved, and a sufficient condition for strategy extinction is given. For the stochastic model with impulses, the existence of positive periodic solutions is proved. Numerical results show that noise and impulses directly affect the model, but the periodicity of the model does not change. 展开更多
关键词 Periodic solution Stochastic game IMPULSES Strategy extinct
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部