期刊文献+
共找到7,747篇文章
< 1 2 250 >
每页显示 20 50 100
On Naturalism in Stephen Crane's The Open Boat
1
作者 王秀红 陈贝贝 《海外英语》 2014年第17期212-217,共6页
Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at ... Stephen Crane is one of the greatest figures in the history of American literature and his novella The Open Boat is widely known by people all over the world as a representative work of Naturalism. This paper aims at exploring Naturalism in Stephen Crane's The Open Boat,which will guide the readers to understand American Naturalism accurately and thoroughly. It firstly introduces the author and his novel The Open Boat. Secondly,it progressively dissects Naturalism. It not only analyses the general characteristics of Naturalism with details in The Open Boat,but also interprets the distinguishing features of American Naturalism so that readers can better understand the features of American Naturalism. Through textual perusal,it further studies the unique characteristics of Stephen Crane's Naturalism and lays particular emphasis on Crane's special concern on the awakening of humanity. It is hoped that this thesis can help readers get an in-depth comprehension of Naturalism and gain some inspiration from TheOpenBoat. 展开更多
关键词 naturalism Stephen CRANE the OPEN BOAT
下载PDF
Brief Analysis on Naturalism and Realism in Desire Under the Elms
2
作者 孙德梅 《海外英语》 2019年第2期202-203,共2页
Desire Under the Elms was a drama written by Eugene O'Neill in 1924,which is called the first greatest drama in American history.Through analyzing the naturalistic features in this drama and the combination of nat... Desire Under the Elms was a drama written by Eugene O'Neill in 1924,which is called the first greatest drama in American history.Through analyzing the naturalistic features in this drama and the combination of naturalism and realism reflected in Desire Under the Elms,this article aims to help readers understand the lines and the relevant connotations better. 展开更多
关键词 Desire Under the ELMS naturalism REALISM
下载PDF
Naturalism in Light in August
3
作者 胡丽娟 李敏 《海外英语》 2013年第22期213-214,216,共3页
William Faulkner is acclaimed as one of the most outstanding American writers of the twentieth century,enjoying a high reputation as a first-rate writer in American literature.Light in August is considered as a master... William Faulkner is acclaimed as one of the most outstanding American writers of the twentieth century,enjoying a high reputation as a first-rate writer in American literature.Light in August is considered as a masterpiece of Faulkner.With pro found moral significance,minute psychological descriptions and unique narrative techniques,William Faulkner passes his judg ments on the human life and the contradiction of human nature. 展开更多
关键词 naturalism RACISM BEING in the world INDIFFERENCE
下载PDF
Naturalism in“To build a Fire”
4
作者 李锦 《海外英语》 2014年第7X期178-179,共2页
The short story"To build a Fire"by Jack London tells about the relationship between man and nature. Involving such themes as fear, death, and the individual versus nature,‘‘To Build a Fire''is a na... The short story"To build a Fire"by Jack London tells about the relationship between man and nature. Involving such themes as fear, death, and the individual versus nature,‘‘To Build a Fire''is a naturalistic work of fiction in which Jack London depicts human beings as subject to the laws of nature and controlled by their environment and their physical makeup. 展开更多
关键词 naturalism human FORCE of NATURE ENVIRONMENT confl
下载PDF
Comparison of the Naturalism in Sister Carrie and The Open Boat
5
作者 孙雪莹 《海外英语》 2015年第10期181-181,共1页
Theodore Dreiser's Sister Carrie and Stephen Crane's The Open Boat are American naturalistic works in the 19 th centu-ry.The two novels reveal the writers' awareness of the American people's social sit... Theodore Dreiser's Sister Carrie and Stephen Crane's The Open Boat are American naturalistic works in the 19 th centu-ry.The two novels reveal the writers' awareness of the American people's social situation.This paper will analyze Sister Carrie andThe Open Boat from the point of naturalism. 展开更多
关键词 AMERICAN naturalism SISTER CARRIE The Open BOAT
下载PDF
Philosophy of Mathematics: Naturalism vs. Category Theory
6
作者 Milan Tasic 《Journal of Philosophy Study》 2013年第10期929-944,共16页
Although E Maddy (1997) says on naturalism: "This is not, in itself, a philosophy of mathematics [...]" (161), already by its name, or by those whose interest has called on it (Quine, Putnam et al.) ... it an... Although E Maddy (1997) says on naturalism: "This is not, in itself, a philosophy of mathematics [...]" (161), already by its name, or by those whose interest has called on it (Quine, Putnam et al.) ... it anyhow reveals desire to be it. Insofar as otherwise, the semantic potential of the word leaves far behind it (after all scarce) results it achieved from the relation of an exact (mathematical) expression and (overly rich) intuitive reality of Being. We plead here already from the perspective of the slogan "One and All" of the first philosopher: Tales, when by the number (which one forebodes) one could go to such an extent into areas of reality (Pythagoras), or when (especially in the human sphere) is being over again actual final cause of Aristotle the philosophy and the mathematics to accomplish far more fruitful encounter with the Being. Alain Badiou (1988) has already pointed that: "Mathematics is ontology," and the category theory in mathematics, having covered by itself other fields of this science, continues to find applications in a series of"non-traditional" domains of reality. In that correlation the philosophy can express its (primary) needs for truth, justice, beauty, ... as well as for the overall development in the sense of purpose--also because of an undreamed power of the technological development (of hardwares and softwares) today. Namely, the naturalism in mathematics, which developed an abundant reflection on the place (importance of) the mathematical idiom in sciences--in the balance of criticism--has come rather to meager provisions, such as: "preestablished harmony of thinking," "ontic commitment," (Quine 1960) "the hygiene of mind," (Maddy 1996) "success argument," (Putnam 1975) "pragmatic argument," (Resnik 1981) etc., which only are few places from the encounter of an exact expression such as is mathematical one and the reality of natuural sciences. Instead of philosophy of mathematics to radicalize its claims from the perspective of that (powerful) mathematical idiom and the excessive reality of Being and man's place in it--this time, in the spirit of biocosmology (neo-Aristotelism). 展开更多
关键词 naturalism indispensability argument ontology MATHEMATICS CATEGORY final cause biocosmology
下载PDF
Why Free Will Is Logically Not Possible within Naturalism
7
作者 Michael Prost 《Journal of Philosophy Study》 2017年第2期100-109,共10页
One of the most intriguing problems of philosophy and of mankind is the question whether humans have a free will. This question is heavily disputed between natural scientists and especially neuroscientists, who deny f... One of the most intriguing problems of philosophy and of mankind is the question whether humans have a free will. This question is heavily disputed between natural scientists and especially neuroscientists, who deny free will, and philosophers and other groups, who insist on free will. It is perplexing that both sides base their premise on the same precondition, namely naturalism. We will prove that naturalism automatically leads to physicalism, to materialism, and to reductionism. We will also prove here that it is logically not possible to have a free will if naturalism is true. Free will definitely requires an additional substance, a non-material soul, which cannot be part of our universe. This must not be in contradiction to our current knowledge of natural sciences. 展开更多
关键词 free will naturalism physical realization of will decisions determinism/indeterminism compatibilism libertarianism
下载PDF
A Brief Analysis of Naturalism in“To Build a Fire”
8
作者 孙静 《海外英语》 2021年第18期238-240,共3页
Jack London is one of the most outstanding naturalistic writers in America who composed many renowned full-length novels.Jack London’s short story,"To Build a Fire"is a good reflection of naturalistic tende... Jack London is one of the most outstanding naturalistic writers in America who composed many renowned full-length novels.Jack London’s short story,"To Build a Fire"is a good reflection of naturalistic tendencies.It chooses"To Build a Fire"so as to fully understand his perspective of naturalism.First,it provides a brief introduction to Jack London and this short story.Second,it specifically displays naturalism in this short story from four aspects.Among them,objective authenticity is the most distinctive feature in naturalistic elements.Meanwhile,his literature creation is also deeply influenced by Darwin’s theory of evolution.It aims to investigate gold seeker’s failure that reflects natural selection and theory of survival of the fittest.Finally,it concludes that only by respecting nature can human beings survive in natural selection.Through the analysis of gold seeker’s tragic fate,it warns that the readers should master wild survival skills and live in harmony with nature. 展开更多
关键词 Jack London naturalism "To Build a Fire" survival of the fittest natural selection
下载PDF
Potential role and therapeutic implications of glutathione peroxidase 4 in the treatment of Alzheimer's disease
9
作者 Yanxin Shen Guimei Zhang +4 位作者 Chunxiao Wei Panpan Zhao Yongchun Wang Mingxi Li Li Sun 《Neural Regeneration Research》 SCIE CAS 2025年第3期613-631,共19页
Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxid... Alzheimer's disease is an age-related neurodegenerative disorder with a complex and incompletely understood pathogenesis. Despite extensive research, a cure for Alzheimer's disease has not yet been found. Oxidative stress mediates excessive oxidative responses, and its involvement in Alzheimer's disease pathogenesis as a primary or secondary pathological event is widely accepted. As a member of the selenium-containing antioxidant enzyme family, glutathione peroxidase 4 reduces esterified phospholipid hydroperoxides to maintain cellular redox homeostasis. With the discovery of ferroptosis, the central role of glutathione peroxidase 4 in anti-lipid peroxidation in several diseases, including Alzheimer's disease, has received widespread attention. Increasing evidence suggests that glutathione peroxidase 4 expression is inhibited in the Alzheimer's disease brain, resulting in oxidative stress, inflammation, ferroptosis, and apoptosis, which are closely associated with pathological damage in Alzheimer's disease. Several therapeutic approaches, such as small molecule drugs, natural plant products, and non-pharmacological treatments, ameliorate pathological damage and cognitive function in Alzheimer's disease by promoting glutathione peroxidase 4 expression and enhancing glutathione peroxidase 4 activity. Therefore, glutathione peroxidase 4 upregulation may be a promising strategy for the treatment of Alzheimer's disease. This review provides an overview of the gene structure, biological functions, and regulatory mechanisms of glutathione peroxidase 4, a discussion on the important role of glutathione peroxidase 4 in pathological events closely related to Alzheimer's disease, and a summary of the advances in small-molecule drugs, natural plant products, and non-pharmacological therapies targeting glutathione peroxidase 4 for the treatment of Alzheimer's disease. Most prior studies on this subject used animal models, and relevant clinical studies are lacking. Future clinical trials are required to validate the therapeutic effects of strategies targeting glutathione peroxidase 4 in the treatment of Alzheimer's disease. 展开更多
关键词 apoptosis ferroptosis inflammation lipid peroxidation natural plant products neurodegenerative disorder NEUROPROTECTION oxidative stress small-molecule drugs
下载PDF
Heterogeneity of mature oligodendrocytes in the central nervous system
10
作者 Chao Weng Adam M.R.Groh +4 位作者 Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.R.Wayne Moore Jack P.Antel 《Neural Regeneration Research》 SCIE CAS 2025年第5期1336-1349,共14页
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio... Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology. 展开更多
关键词 aging central nervous system diseases electron microscopy HETEROGENEITY immunohistochemistry myelin sheath natural history NEUROGLIA OLIGODENDROGLIA single-cell gene expression analysis
下载PDF
Impacts of Nutlin-3a and exercise on murine double minute 2-enriched glioma treatment
11
作者 Yisheng Chen Zhongcheng Fan +11 位作者 Zhiwen Luo Xueran Kang Renwen Wan Fangqi Li Weiwei Lin Zhihua Han Beijie Qi Jinrong Lin Yaying Sun Jiebin Huang Yuzhen Xu Shiyi Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1135-1152,共18页
Recent research has demonstrated the impact of physical activity on the prognosis of glioma patients,with evidence suggesting exercise may reduce mortality risks and aid neural regeneration.The role of the small ubiqu... Recent research has demonstrated the impact of physical activity on the prognosis of glioma patients,with evidence suggesting exercise may reduce mortality risks and aid neural regeneration.The role of the small ubiquitin-like modifier(SUMO)protein,especially post-exercise,in cancer progression,is gaining attention,as are the potential anti-cancer effects of SUMOylation.We used machine learning to create the exercise and SUMO-related gene signature(ESLRS).This signature shows how physical activity might help improve the outlook for low-grade glioma and other cancers.We demonstrated the prognostic and immunotherapeutic significance of ESLRS markers,specifically highlighting how murine double minute 2(MDM2),a component of the ESLRS,can be targeted by nutlin-3.This underscores the intricate relationship between natural compounds such as nutlin-3 and immune regulation.Using comprehensive CRISPR screening,we validated the effects of specific ESLRS genes on low-grade glioma progression.We also revealed insights into the effectiveness of Nutlin-3a as a potent MDM2 inhibitor through molecular docking and dynamic simulation.Nutlin-3a inhibited glioma cell proliferation and activated the p53 pathway.Its efficacy decreased with MDM2 overexpression,and this was reversed by Nutlin-3a or exercise.Experiments using a low-grade glioma mouse model highlighted the effect of physical activity on oxidative stress and molecular pathway regulation.Notably,both physical exercise and Nutlin-3a administration improved physical function in mice bearing tumors derived from MDM2-overexpressing cells.These results suggest the potential for Nutlin-3a,an MDM2 inhibitor,with physical exercise as a therapeutic approach for glioma management.Our research also supports the use of natural products for therapy and sheds light on the interaction of exercise,natural products,and immune regulation in cancer treatment. 展开更多
关键词 exercise and SUMO-related gene signatures(ESLRS) glioblastoma management low-grade glioma natural bioactives neural regeneration physical exercise
下载PDF
Harnessing artificial intelligence for identifying conflicts of interest in research
12
作者 Abdulqadir J Nashwan 《World Journal of Methodology》 2025年第1期6-8,共3页
This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recogni... This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recognition,and natural language processing techniques,AI offers innovative solutions for enhancing transparency and integrity in research.This editorial discusses how AI can automatically detect COIs,integrate data from various sources,and streamline reporting processes,thereby maintaining the credibility of scientific findings. 展开更多
关键词 Artificial intelligence Conflicts of interest TRANSPARENCY Research integrity Natural language processing
下载PDF
Plantinga's Evolutionary Argument against Naturalism Revisited
13
《Fudan Journal of the Humanities and Social Sciences》 2012年第1期95-114,共20页
Alvin Plantinga's Evolutionary Argument against Naturalism (hereafter "EAAN") is an argument intended to prove that atheism is not highly probably true in the Darwinian framework. Many critics believe that this a... Alvin Plantinga's Evolutionary Argument against Naturalism (hereafter "EAAN") is an argument intended to prove that atheism is not highly probably true in the Darwinian framework. Many critics believe that this argument Cannot work. I am one of them; but I have a different perspective. In my view, although EAAN was originally elaborated for defending theism, the failure of EAAN itself will not consequently undermine theism (as a religious position), but will definitely undermine reliabilism (as an epistemological position). My points include: (1) in Plantinga's epistemological reliabilist narrative, it is quite hard to clarify the meaning of the term "reliability" (as a key word of his whole narrative), and it is the ambiguity of this term that makes some steps in Plantinga's argument more confusing than it ought to be; (2) conversely, if he wiped out this terminological ambiguity, the whole EAANnarrative based on "reliability" would have to be given up, and this cost may be too high for any EAANadherent to pay. 展开更多
关键词 Evolutionary Argument against naturalism proper functionalism reliability RELIABILISM
原文传递
Humanism or Naturalism?-In Defence of Human-centrism
14
作者 刘福森 李力新 《Social Sciences in China》 1997年第2期120-124,195,共6页
关键词 Humanism or naturalism In Defence of Human-centrism
原文传递
Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications 被引量:5
15
作者 Shuai Liu Jiang-Ming Yu +11 位作者 Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou 《Military Medical Research》 SCIE CAS CSCD 2024年第1期50-79,共30页
Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds bas... Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field. 展开更多
关键词 Biomimic SCAFFOLD BIOSYNTHESIS Natural biomaterial Tissue engineering
下载PDF
Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents 被引量:2
16
作者 Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期846-854,共9页
Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinester... Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes. 展开更多
关键词 Alzheimer’s disease EPIGENETICS genes METHYLATION natural products
下载PDF
Synthetic polymers:A review of applications in drilling fluids 被引量:2
17
作者 Shadfar Davoodi Mohammed Al-Shargabi +2 位作者 David A.Wood Valeriy S.Rukavishnikov Konstantin M.Minaev 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期475-518,共44页
With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complicatio... With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various complications.Currently,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(SPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling process.However,compared to modified natural polymers,SPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization reactions.SPs provide substantial flexibility in their design.Moreover,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling fluids.They can be classified based on chemical ingredients,type of reaction,and their responses to heating.However,some of SPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent SP use in some medium and deep wells.Thus,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of SPs in drilling fluids.The contributions of SPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in detail.The mechanisms,impacts,and advances achieved when SPs are added to drilling fluids are also described.The typical challenges encountered by SPs when deployed in drilling fluids and their advantages and drawbacks are also discussed.Economic issues also impact the applications of SPs in drilling fluids.Consequently,the cost of the most relevant SPs,and the monomers used in their synthesis,are assessed.Environmental impacts of SPs when deployed in drilling fluids,and their manufacturing processes are identified,together with advances in SP-treatment methods aimed at reducing those impacts.Recommendations for required future research addressing SP property and performance gaps are provided. 展开更多
关键词 Synthetic versus natural polymers Nanopolymers Drilling fluid additives LUBRICITY Clay swelling Hole cleaning
下载PDF
Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation 被引量:2
18
作者 Wen Xiao Peng Dong +6 位作者 Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期75-84,共10页
Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficien... Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing. 展开更多
关键词 Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation
下载PDF
Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production 被引量:1
19
作者 SUN Huan-zhao CHANG Yuan-jiang +4 位作者 SUN Bao-jiang WANG Kang CHEN Guo-ming LI Hao DAI Yong-guo 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期338-351,共14页
Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence d... Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate decomposition.Therefore,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production well.However,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during production.To fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate decomposition.Based on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is developed.The analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability deterioration.The higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even instability.This work can provide a theoretical reference for the stability maintaining of the production well. 展开更多
关键词 natural gas hydrate production well depressurization production formation deformation stability deterioration
下载PDF
Predicting the friction angle of clays using a multi-layer perceptron neural network enhanced by yeo-johnson transformation and coral reefs optimization 被引量:1
20
作者 Libing Yang Trung Nguyen-Thoi Trung-Tin Tran 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期3982-4003,共22页
The accurate prediction of the friction angle of clays is crucial for assessing slope stability in engineering applications.This study addresses the importance of estimating the friction angle and presents the develop... The accurate prediction of the friction angle of clays is crucial for assessing slope stability in engineering applications.This study addresses the importance of estimating the friction angle and presents the development of four soft computing models:YJ-FPA-MLPnet,YJ-CRO-MLPnet,YJ-ACOC-MLPnet,and YJCSA-MLPnet.First of all,the Yeo-Johnson(YJ)transformation technique was used to stabilize the variance of data and make it more suitable for parametric statistical models that assume normality and equal variances.This technique is expected to improve the accuracy of friction angle prediction models.The friction angle prediction models then utilized multi-layer perceptron neural networks(MLPnet)and metaheuristic optimization algorithms to further enhance performance,including flower pollination algorithm(FPA),coral reefs optimization(CRO),ant colony optimization continuous(ACOC),and cuckoo search algorithm(CSA).The prediction models without the YJ technique,i.e.FPA-MLPnet,CRO-MLPnet,ACOC-MLPnet,and CSA-MLPnet,were then compared to those with the YJ technique,i.e.YJ-FPA-MLPnet,YJ-CRO-MLPnet,YJ-ACOC-MLPnet,and YJ-CSA-MLPnet.Among these,the YJ-CRO-MLPnet model demonstrated superior reliability,achieving an accuracy of up to 83%in predicting the friction angle of clay in practical engineering scenarios.This improvement is significant,as it represents an increase from 1.3%to approximately 20%compared to the models that did not utilize the YJ transformation technique. 展开更多
关键词 Natural hazards Slope stability Friction angle CLAY Soft computing models Geotechnical engineering
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部