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Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications 被引量:2
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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
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Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents 被引量:1
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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
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Natural Disaster Risk Monitoring for Immovable Cultural Relics Based on Digital Twin 被引量:1
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作者 LI Bolun DONG Youqiang +2 位作者 QIAO Yunfei HOU Miaole WEN Caihuan 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期90-104,共15页
Natural disaster risk monitoring is an important task for disaster prevention and reduction.In the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicato... Natural disaster risk monitoring is an important task for disaster prevention and reduction.In the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicators of natural disaster risk monitoring are complex.How to achieve intelligent perception and monitoring of natural disaster risk for immovable cultural relics has always been a focus and a challenge for researchers.Based on the analysis of the concepts and issues related to the natural disaster risk of immovable cultural relics,this paper proposes a framework for natural disaster risk monitoring for immovable cultural relics based on the digital twin.This framework focuses on risk monitoring,including the physical entities of natural disaster risk for immovable cultural relics,monitoring indicators,and virtual entity construction.A platform for monitoring the natural disaster risk of immovable cultural relics is proposed.Using the Puzhou Ancient City Site as a test bed,the proposed concept can be used for monitoring the natural disaster risk of immovable cultural relics at different scales. 展开更多
关键词 immovable cultural relics natural disaster risk digital twin risk monitoring
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New insights into the deposition of natural gas hydrate on pipeline surfaces:A molecular dynamics simulation study
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作者 Jun Zhang Hai-Qiang Fu +7 位作者 Mu-Zhi Guo Zhao Wang Li-Wen Li Qi Yin You-Guo Yan Wei Wei Wei-Feng Han Jie Zhong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期694-704,共11页
Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low temperatures.Reducing hydrate adhesion on pipelines is viewed as an efficient way to prevent N... Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low temperatures.Reducing hydrate adhesion on pipelines is viewed as an efficient way to prevent NGH blockages.Previous studies suggested the water film can greatly increase hydrate adhesion in gas-dominant system.Herein,by performing the molecular dynamics simulations,we find in water-dominant system,the water film plays different roles in hydrate deposition on Fe and its corrosion surfaces.Specifically,due to the strong affinity of water on Fe surface,the deposited hydrate cannot convert the adsorbed water into hydrate,thus,a water film exists.As water affinities decrease(Fe>Fe_(2)O_(3)>FeO>Fe_(3)O_(4)),adsorbed water would convert to amorphous hydrate on Fe_(2)O_(3)and form the ordered hydrate on FeO and Fe_(3)O_(4)after hydrate deposition.While absorbed water film converts to amorphous or to hydrate,the adhesion strength of hydrate continuously increases(Fe<Fe_(2)O_(3)<FeO<Fe_(3)O_(4)).This is because the detachment of deposited hydrate prefers to occur at soft region of liquid layer,the process of which becomes harder as liquid layer vanishes.As a result,contrary to gas-dominant system,the water film plays the weakening roles on hydrate adhesion in water-dominant system.Overall,our results can help to better understand the hydrate deposition mechanisms on Fe and its corrosion surfaces and suggest hydrate deposition can be adjusted by changing water affinities on pipeline surfaces. 展开更多
关键词 DEPOSITION natural gas hydrate Pipelines Water affinity Adhesion strength
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Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient
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作者 Guangxia Jin Yuxue Wu Feng Wei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期212-219,共8页
The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar co... The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC). 展开更多
关键词 Solvent gradient Twin-column recycling chromatography PURIFICATION Minor component natural products
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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate
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作者 Zhengchao Ren Lei Liu +1 位作者 Fang Yin Xiaoni Liu 《Forest Ecosystems》 SCIE CSCD 2024年第2期184-192,共9页
Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional pr... Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention worldwide.However,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate warming.In this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation fluctuations.To achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV classification.We find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and precipitation.Notably,we observe an unexpected transition between tundra and savanna despite their geographical distance.The shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each group.Indeed,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing climate.The spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide. 展开更多
关键词 Potential natural vegetation Global warming Vegetation classification Predicted model CSCS
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Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging
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作者 Rumeng Xu Chunchun Yin +4 位作者 Jingxuan You Jinming Zhang Qinyong Mi Jin Wu Jun Zhang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期927-936,共10页
Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and ... Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes. 展开更多
关键词 Thermoplastic coating Bio-degradable adhesive natural products Cellulose Eco-friendly packaging
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Research progress of CO_(2) capture and mineralization based on natural minerals
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作者 Chenguang Qian Chunquan Li +5 位作者 Peng Huang Jialin Liang Xin Zhang Jifa Wang Jianbing Wang Zhiming Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1208-1227,共20页
Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant ... Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant reserves,low cost,excellent mechanical prop-erties,and chemical stability.Over the past decades,various methods,such as those involving heat,acid,alkali,organic amine,amino sil-ane,and ionic liquid,have been employed to enhance the CO_(2) capture performance of natural minerals to attain high specific surface area,a large number of pore structures,and rich active sites.Future research on CO_(2) capture by natural minerals will focus on the full utiliza-tion of the properties of natural minerals,adoption of suitable modification methods,and preparation of composite materials with high specific surface area and rich active sites.In addition,we provide a summary of the principle and technical route of direct and indirect mineralization of CO_(2) by natural minerals.This process uses minerals with high calcium and magnesium contents,such as forsterite(Mg_(2)SiO_(4)),serpentine[Mg_(3)Si_(2)O(OH)_(4)],and wollastonite(CaSiO_(3)).The research status of indirect mineralization of CO_(2) using hydro-chloric acid,acetic acid,molten salt,and ammonium salt as media is also introduced in detail.The recovery of additives and high-value-added products during the mineralization process to increase economic benefits is another focus of future research on CO_(2) mineralization by natural minerals. 展开更多
关键词 natural mineral carbon dioxide capture MODIFICATION composite material carbon dioxide mineralization
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Rapid discovery of a novel “green” and natural GST inhibitor for sensitizing hepatocellular carcinoma to Cisplatin by visual screening strategy
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作者 Linxi Mao Yan Qin +7 位作者 Jialong Fan Wei Yang Bin Li Liang Cao Liqin Yuan Mengyun Wang Bin Liu Wei Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期693-706,共14页
Over-expression of glutathione S-transferase(GST)can promote Cisplatin resistance in hepatocellular carcinoma(HCC)treatment.Hence,inhibiting GST is an attractive strategy to improve Cisplatin sensitivity in HCC therap... Over-expression of glutathione S-transferase(GST)can promote Cisplatin resistance in hepatocellular carcinoma(HCC)treatment.Hence,inhibiting GST is an attractive strategy to improve Cisplatin sensitivity in HCC therapy.Although several synthesized GST inhibitors have been developed,the side effects and narrow spectrum for anticancer seriously limit their clinical application.Considering the abundance of natural compounds with anticancer activity,this study developed a rapid fluorescence technique to screen“green”natural GST inhibitors with high specificity.The fluorescence assay demonstrated that schisanlactone B(hereafter abbreviated as C1)isolated from Xue tong significantly down-regulated GST levels in Cisplatin-resistant HCC cells in vitro and in vivo.Importantly,C1 can selectively kill HCC cells from normal liver cells,effectively improving the therapeutic effect of Cisplatin on HCC mice by downregulating GST expression.Considering the high GST levels in HCC patients,this compound demonstrated the high potential for sensitizing HCC therapy in clinical practice by down-regulating GST levels. 展开更多
关键词 GST Drug resistance Fluorescence HEPATOCARCINOMA natural compound C1 “Green”GST inhibitor
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Stabilizing perovskite precursors with the reductive natural amino acid for printable mesoscopic perovskite solar cells
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作者 Wenjing Hu Jian Yang +9 位作者 Chuang Yang Xufeng Xiao Chaoyang Wang Zhaozhen Cui Qiaojiao Gao Jianhang Qi Minghao Xia Yaqiong Su Anyi Mei Hongwei Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期32-39,I0003,共9页
Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device perform... Solution processability significantly advances the development of highly-efficient perovskite solar cells.However,the precursor solution tends to undergo irreversible degradation reactions,impairing the device performance and reproducibility.Here,we utilize a reductive natural amino acid,Nacetylcysteine(NALC),to stabilize the precursor solution for printable carbon-based hole-conductorfree mesoscopic perovskite solar cells.We find that I_(2) can be generated in the aged solution containing methylammonium iodide(MI) in an inert atmosphere and speed up the MA-FA^(+)(formamidinium) reaction which produces large-size cations and hinders the formation of perovskite phase.NALC effectively stabilizes the precursor via its sulfhydryl group which reduces I_(2) back to I^(-)and provides H^(+).The NALC-stabilized precursor which is aged for 1440 h leads to devices with a power conversion efficiency equivalent to 98% of that for devices prepared with the fresh precursor.Furthermore,NALC improves the device power conversion efficiency from 16.16% to 18.41% along with enhanced stability under atmospheric conditions by modifying grain boundaries in perovskite films and reducing associated defects. 展开更多
关键词 Perovskite solar cells Perovskite precursor Degradation STABILIZATION Reductive natural amino acid
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Formation of Natural Melanin/TiO_(2) Nanostructure Hybrids with Enhanced Optical,Thermal and Magnetic Properties as a Soft Material
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作者 Saja Algessair Nawal Madkhali 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期613-620,共8页
The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated ... The natural Melanin/TiO_(2) was synthesized by the use of ultrasonication under UV radiation.The influence of natural melanin on the structural,optical and thermal properties of TiO_(2) nanoparticles was investigated by using Fourier transform infrared spectroscopy,thermogravimetric analysis and UV-Vis spectroscopy.It was observed that incorporating natural melanin on TiO_(2) nanoparticles(TiO_(2)-Mel)occurred at 2.01 eV with a low value of Urbach energy around 100 meV indicating improvement in the crystalline structure.Magnetic measurement at room temperature showed diamagnetic behavior.Furthermore,thermal results showed that TiO_(2)-Mel is stable even at temperatures up to 400℃.According to the results obtained by the thermal stability of melanin with titanium dioxide,it can be a good candidate in many applications such as solar cells and optoelectronics. 展开更多
关键词 natural melanin/TiO_(2) thermal stability OPTOELECTRONIC NANOSTRUCTURE UV radiation
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OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization
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作者 Tiesen Li Ting Chen +5 位作者 Yinghui Ye Peng Dong TinghaiWang Qingyan Cui Chan Wang Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期51-59,共9页
A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal cry... A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis conditions.Characterizations show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ratio.Significantly,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,respectively.This work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance. 展开更多
关键词 FeZSM-22 zeolite OSDA-free synthesis natural minerals n-octane hydroisomerization
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Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation
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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
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Energy Design and Optimization of Greenhouse by Natural Convection
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作者 H.Benzzine H.Labrim +3 位作者 Aouatif Saad Y.Achour D.Zejli R.El Bouayadi 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1903-1913,共11页
This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural ventilation.The primary objective of this study is to evaluate various ventilation... This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural ventilation.The primary objective of this study is to evaluate various ventilation strategies to enhance energy efficiency and optimize crop production in agricultural greenhouses.Employing advanced numerical simulation tools,the study conducts a comprehensive assessment of natural ventilation’s effectiveness under real-world conditions.The results underscore the crucial role of the stack effect and strategic window positioning in greenhouse cooling,providing valuable insights for greenhouse designers.Our findings shed light on the significant benefits of optimized ventilation and also offer practical implications for improving greenhouse design,ensuring sustainable and efficient agricultural practices.The study demonstrated energy savings in cooling from November to April,with a maximum saving of 680 kWh in March,indicating the effectiveness of strategically positioning windows to leverage the stack effect.This approach enhances plant growth and reduces the need for costly cooling systems,thereby improving overall energy efficiency and lowering operational expenses. 展开更多
关键词 ENERGY GREENHOUSE COOLING natural ventilation SIMULATION TEMPERATURE
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Natural variation of GmFNSII-2 contributes to drought resistance by modulating enzyme activity in soybean
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作者 Huihui Gao Pengcheng Wei +12 位作者 Yongzhe Gu Pengbin Tang Yifan Shen Lei Yang Linxin Dong Haowei Zheng Kuo Shu Mayamiko Masangano Bin Dong Long Miao Jiajia Li Lijuan Qiu Xiaobo Wang 《The Crop Journal》 SCIE CSCD 2024年第2期529-539,共11页
As an essential crop that provides vegetable oil and protein,soybean(Glycine max(L.)Merr.)is widely planted all over the world.However,the scarcity of water resources worldwide has seriously impacted on the quality an... As an essential crop that provides vegetable oil and protein,soybean(Glycine max(L.)Merr.)is widely planted all over the world.However,the scarcity of water resources worldwide has seriously impacted on the quality and yield of soybean.To address this,exploring excellent genes for improving drought resistance in soybean is crucial.In this study,we identified natural variations of GmFNSII-2(flavone synthase II)significantly affect the drought resistance of soybeans.Through sequence analysis of GmFNSII-2 in 632 cultivated and 44 wild soybeans nine haplotypes were identified.The full-length allele GmFNSII-2^(C),but not the truncated allele GmFNSII-2^(A) possessing a nonsense nucleotide variation,increased enzyme activity.Further research found that GmDREB3,known to increase soybean drought resistance,bound to the promoter region of GmFNSII-2^(C).GmDREB3 positively regulated the expression of GmFNSII-2^(C),increased flavone synthase abundance and improved the drought resistance.Furthermore,a singlebase mutation in the GmFNSII-2^(C) promoter generated an additional drought response element(CCCCT),which had stronger interaction strength with GmDREB3 and increased its transcriptional activity under drought conditions.The frequency of drought-resistant soybean varieties with Hap 1(Pro:GmFNSII-2^(C))has increased,suggesting that this haplotype may be selected during soybean breeding.In summary,GmFNSII-2^(C) could be used for molecular breeding of drought-tolerant soybean. 展开更多
关键词 Drought stress Flavone synthase GmFNSII-2 natural variation Drought response element
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How topography and neighbor shape the fate of trees in subtropical forest restoration:Environmental filtering and resource competition drive natural regeneration
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作者 Haonan Zhang Xingshuo Zhang +7 位作者 Yingying Lv Yanyan Ni Baokun Xu Xiangnan Han Xiao Cao Qingpei Yang Wanggu Xu Zhedong Qian 《Forest Ecosystems》 SCIE CSCD 2024年第1期73-86,共14页
The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering d... The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration. 展开更多
关键词 natural regeneration MICROTOPOGRAPHY Neighborhood effects Mortality and recruitment
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Enhancing transboundary natural tourism resources governance:unveiling the spatial pattern and its influencing factors
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作者 ZHANG Shengrui ZHANG Tongyan +1 位作者 JU Hongrun WANG Yingjie 《Journal of Mountain Science》 SCIE CSCD 2024年第3期973-986,共14页
Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensi... Tourism resources that span provincial boundaries in China play a pivotal role in regional development,yet effective governance poses persistent challenges.This study addresses this issue by constructing a comprehensive database of transboundary natural tourism resources(TNTR)through amalgamation of diverse data sources.Utilizing the Getis-Ord Gi^(*),kernel density estimation,and geographical detectors,we scrutinize the spatial patterns of TNTR,focusing on both named and unnamed entities,while exploring the influencing factors.Our findings reveal 7883 identified TNTR in China,with mountain tourism resources emerging as the predominant type.Among provinces,Hunan boasts the highest count,while Shanghai exhibits the lowest.Southern China demonstrates a pronounced clustering trend in TNTR distribution,with the spatial arrangement of biological landscapes appearing more random compared to geological and water landscapes.Western China,characterized by intricate terrain,exhibits fewer TNTR,concurrently unveiling a significant presence of unnamed natural tourism resources.Crucially,administrative segmentation influences TNTR development,generating disparities in regional goals,developmental stages and intensities,and management approaches.In response to these variations,we advocate for strengthening the naming of the unnamed transboundary tourism resources,constructing a geographic database of TNTR for government and establishing a collaborative management mechanism based on TNTR database.Our research contributes to elucidating the intricate landscape of TNTR,offering insights for tailored governance strategies in the realm of cross-provincial tourism resource management. 展开更多
关键词 Transboundary natural tourism resources(TNTR) Spatial difference Spatial autocorrelation Governance optimization China
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Development,challenges and strategies of natural gas industry under carbon neutral target in China
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作者 ZOU Caineng LIN Minjie +10 位作者 MA Feng LIU Hanlin YANG Zhi ZHANG Guosheng YANG Yichao GUAN Chunxiao LIANG Yingbo WANG Ying XIONG Bo YU Hao YU Ping 《Petroleum Exploration and Development》 SCIE 2024年第2期476-497,共22页
In the mid-21st century,natural gas will enter its golden age,and the era of natural gas is arriving.This paper reviews the development stages of global natural gas industry and the enlightenment of American shale gas... In the mid-21st century,natural gas will enter its golden age,and the era of natural gas is arriving.This paper reviews the development stages of global natural gas industry and the enlightenment of American shale gas revolution,summarizes the development history and achievements of the natural gas industry in China,analyzes the status and challenges of natural gas in the green and low-carbon energy transition,and puts forward the natural gas industry development strategies under carbon neutral target in China.The natural gas industry in China has experienced three periods:start,growth,and leap forward.At present,China has become the fourth largest natural gas producer and third largest natural gas consumer in the world,and has made great achievements in natural gas exploration and development theory and technology,providing important support for the growth of production and reserves.China has set its goal of carbon neutrality to promote green and sustainable development,which brings opportunities and challenges for natural gas industry.Natural gas has significant low-carbon advantages,and gas-electric peak shaving boosts new energy development;the difficulty and cost of development are more prominent.For the national energy security and harmonious development between economy and ecology under the carbon neutral goal,based on the principle of"comprehensive planning,technological innovation,multi-energy complementarity,diversified integration,flexibility and efficiency,optimization and upgrading",the construction of the production-supplystorage-marketing system has to be improved so as to boost the development of the natural gas industry.First,it is necessary to strengthen efforts in the exploration and development of natural gas,making projects and arrangement in key exploration and development areas,meanwhile,it is urgent to make breakthroughs in key science theories and technologies,so as to increase reserve and production.Second,it should promote green and innovative development of the natural gas by developing new techniques,expanding new fields and integrating with new energy.Third,there is a demand to realize transformation and upgrading of the supply and demand structure of natural gas by strengthening the layout of pipeline gas,liquefied natural gas and the construction of underground gas storage,establishing reserve system for improving abilities of emergency response and adjustment,raising the proportion of natural gas in the primary energy consumption and contributing to the transformation of energy consumption structure,realizing low-carbon resources utilization and clean energy consumption. 展开更多
关键词 carbon neutrality natural gas shale gas tight gas coalbed methane new energy energy transition
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Progress in neurorehabilitation research and the support by the National Natural Science Foundation of China from 2010 to 2022
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作者 Qian Tao Honglu Chao +1 位作者 Dong Fang Dou Dou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期226-232,共7页
The National Natural Science Foundation of China is one of the major funding agencies for neuro rehabilitation research in China.This study reviews the frontier directions and achievements in the field of neurorehabil... The National Natural Science Foundation of China is one of the major funding agencies for neuro rehabilitation research in China.This study reviews the frontier directions and achievements in the field of neurorehabilitation in China and wo rldwide.We used data from the Web of Science Core Collection(WoSCC) database to analyze the publications and data provided by the National Natural Science Foundation of China to analyze funding information.In addition,the prospects for neurorehabilitation research in China are discussed.From 2010 to 2022,a total of 74,220 publications in neurorehabilitation were identified,with there being an overall upward tendency.During this period,the National Natural Science Foundation of China has funded 476 research projects with a total funding of 192.38 million RMB to support neuro rehabilitation research in China.With the support of the National Natural Science Foundation of China,China has made some achievements in neurorehabilitation research.Research related to neurorehabilitation is believed to be making steady and significant progress in China. 展开更多
关键词 brain computer interface invasive neuromodulation National natural Science Foundation of China(NSFC) neuroreha bilitation non-invasive brain stimulation PUBLICATION rehabilitation robotics virtual reality
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Identification of Software Bugs by Analyzing Natural Language-Based Requirements Using Optimized Deep Learning Features
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作者 Qazi Mazhar ul Haq Fahim Arif +4 位作者 Khursheed Aurangzeb Noor ul Ain Javed Ali Khan Saddaf Rubab Muhammad Shahid Anwar 《Computers, Materials & Continua》 SCIE EI 2024年第3期4379-4397,共19页
Software project outcomes heavily depend on natural language requirements,often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements.Researchers are exploring machine learn... Software project outcomes heavily depend on natural language requirements,often causing diverse interpretations and issues like ambiguities and incomplete or faulty requirements.Researchers are exploring machine learning to predict software bugs,but a more precise and general approach is needed.Accurate bug prediction is crucial for software evolution and user training,prompting an investigation into deep and ensemble learning methods.However,these studies are not generalized and efficient when extended to other datasets.Therefore,this paper proposed a hybrid approach combining multiple techniques to explore their effectiveness on bug identification problems.The methods involved feature selection,which is used to reduce the dimensionality and redundancy of features and select only the relevant ones;transfer learning is used to train and test the model on different datasets to analyze how much of the learning is passed to other datasets,and ensemble method is utilized to explore the increase in performance upon combining multiple classifiers in a model.Four National Aeronautics and Space Administration(NASA)and four Promise datasets are used in the study,showing an increase in the model’s performance by providing better Area Under the Receiver Operating Characteristic Curve(AUC-ROC)values when different classifiers were combined.It reveals that using an amalgam of techniques such as those used in this study,feature selection,transfer learning,and ensemble methods prove helpful in optimizing the software bug prediction models and providing high-performing,useful end mode. 展开更多
关键词 natural language processing software bug prediction transfer learning ensemble learning feature selection
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