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The influence of wing morphology upon intraspecific divergence in birds: A global study of subspecies richness
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作者 Haiying Fan Weibin Guo +3 位作者 Buge Lin Zhiqing Hu Changcao Wang Shaobin Li 《Avian Research》 SCIE CSCD 2024年第2期196-201,共6页
Since the time of Darwin,subspecies have been recognized as an initial stage in the evolution of species.However,the impact of dispersal on subspecies richness in birds globally has received little attention,despite d... Since the time of Darwin,subspecies have been recognized as an initial stage in the evolution of species.However,the impact of dispersal on subspecies richness in birds globally has received little attention,despite dispersal being a key factor in determining the rate of evolution and playing a significant role in evolutionary divergence.Therefore,it is important to conduct a comprehensive study to address this issue.In this study,we aimed to assess the association between subspecies richness(measured by the number of subspecies)and dispersal ability(measured by the hand-wing index)on a global scale,using a dataset of over 7000 bird species.Our results revealed a negative correlation between dispersal ability and the number of subspecies,without any quadratic correlation.The wing is a crucial phenotypic trait for birds,and the concept of subspecies is important in speciation theory and conservation biology.Therefore,our findings not only enhance our understanding of the association between avian morphological traits and evolutionary divergence but also have implications for the conservation of avian species diversity. 展开更多
关键词 Dispersal Gene flow Hand-wing index Subspecies richness
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Boosting rate performance of layered lithium-rich cathode materials by oxygen vacancy induced surface multicomponent integration
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作者 Youyou Fang Yuefeng Su +7 位作者 Jinyang Dong Jiayu Zhao Haoyu Wang Yun Lu Bin Zhang Hua Yan Feng Wu Lai Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期250-262,共13页
The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(... The rapid development of electric vehicles and portable energy storage systems demands improvements in the energy density and cost-effectiveness of lithium-ion batteries,a domain in which Lithium-rich layered cathode(LLO)materials inherently excel.However,these materials face practical challenges,such as low initial Coulombic efficiency,inferior cycle/rate performance,and voltage decline during cycling,which limit practical application.Our study introduces a surface multi-component integration strategy that incorporates oxygen vacancies into the pristine LLO material Li1.2Mn_(0.6)Ni_(0.2)O_(2).This process involves a brief citric acid treatment followed by calcination,aiming to explore rate-dependent degradation behavior.The induced surface oxygen vacancies can reduce surface oxygen partial pressure and diminish the generation of O_(2)and other highly reactive oxygen species on the surface,thereby facilitating the activation of Li ions trapped in tetrahedral sites while overcoming transport barriers.Additionally,the formation of a spinel-like phase with 3D Li+diffusion channels significantly improves Li^(+)diffusion kinetics and stabilizes the surface structure.The optimally modified sample boasts a discharge capacity of 299.5 mA h g^(-1)at a 0.1 C and 251.6 mA h g^(-1)at a 1 C during the initial activation cycle,with an impressive capacity of 222.1 mA h g^(-1)at a 5 C.Most notably,it retained nearly 70%of its capacity after 300 cycles at this elevated rate.This straightforward,effective,and highly viable modification strategy provides a crucial resolution for overcoming challenges associated with LLO materials,making them more suitable for practical application. 展开更多
关键词 Lithium-ion battery Layered lithium rich cathode Surface multicomponent integration Rate-dependent degradation and Li^(+) diffusion kinetics
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RICHARD MILLE 人体工学 现代设计进化论
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作者 Chaos 《钟表》 2024年第5期32-33,共2页
RICHARD MILLE理查米尔腕表与众不同的本质就在于其精密复杂的机械结构、美学设计和服贴手腕的人体工学造型,如同佩戴者的第二层肌肤,轻便、纤薄、运动感十足的表体线条。人体工学作为一个独立学科,满打满算也只有不到50年时间,虽然称... RICHARD MILLE理查米尔腕表与众不同的本质就在于其精密复杂的机械结构、美学设计和服贴手腕的人体工学造型,如同佩戴者的第二层肌肤,轻便、纤薄、运动感十足的表体线条。人体工学作为一个独立学科,满打满算也只有不到50年时间,虽然称不上历史悠久,但是它从人自身出发,在以人为主体的前提下研究人们的一切生活、生产活动中综合分析的新思路,正是顺应着社会发展的潮流和实际生活中的最高应用准则。 展开更多
关键词 人体工学 美学设计 运动感 rich 佩戴者 应用准则 独立学科
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RICHARD MILLE 产品永远的核心竞争力
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作者 Chaos 《钟表》 2024年第4期24-25,共2页
2024年的摩根史坦利钟表行业报告中,RICHARDMILLE理查米尔以第六名的位置继续保持着业内领先的地位,市场份额更是从前一年的2.8%增长到了3.1%。然而分析其背后真正的核心推力,当仁不让地来自于这一现代高级钟表品牌有着执着推进、且目... 2024年的摩根史坦利钟表行业报告中,RICHARDMILLE理查米尔以第六名的位置继续保持着业内领先的地位,市场份额更是从前一年的2.8%增长到了3.1%。然而分析其背后真正的核心推力,当仁不让地来自于这一现代高级钟表品牌有着执着推进、且目标清晰的长期产品规划与策略一一即轻便、抗震、符合人体工程学、高科技材质。 展开更多
关键词 核心竞争力 钟表行业 人体工程学 rich 市场份额 ARD
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RICHARD MILLE 红土之王的腕表进化史
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作者 Chaos 《钟表》 2024年第3期24-25,共2页
谈起网球,拉斐尔·纳达尔自然是21世纪最闪亮的明星之一,23年的职业生涯中,他斩获了22个大满贯冠军,从飘逸的西班牙少年到如今永远的红土之王,他的粉丝早已遍及全世界。RICHARDMILLE理查米尔的创始人Richard Mille先生也是粉丝中的... 谈起网球,拉斐尔·纳达尔自然是21世纪最闪亮的明星之一,23年的职业生涯中,他斩获了22个大满贯冠军,从飘逸的西班牙少年到如今永远的红土之王,他的粉丝早已遍及全世界。RICHARDMILLE理查米尔的创始人Richard Mille先生也是粉丝中的一员,早在2008年,他就开始接触纳达尔,那时的纳达尔还是一个拒绝在赛场上戴表的人,在他印象中手表总是很重,打球的时候会觉得不舒适。随着双方的友谊逐渐加深,纳达尔成为了理查米尔的品牌大使,推出了共同参与设计的腕表作品,并最终成就了一个经典的腕表系列,在腕表世界中,这也是一桩妙事。 展开更多
关键词 纳达尔 拉斐尔 rich 理查 米尔 职业生涯 腕表 粉丝
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RICHARD MILLE追求极致再上层楼
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作者 Chaos 《钟表》 2024年第2期24-25,共2页
日前,摩根士丹利(Morgan Stanley)和瑞士LuxeConsult公司联合发布了2024瑞士钟表产业年度报告,整个钟表行业在2023年有了明显的增长,实现了创纪录的267亿瑞士法郎的销售额,其中255亿瑞士法郎归因于腕表销售。其中,四大独立奢侈腕表品牌R... 日前,摩根士丹利(Morgan Stanley)和瑞士LuxeConsult公司联合发布了2024瑞士钟表产业年度报告,整个钟表行业在2023年有了明显的增长,实现了创纪录的267亿瑞士法郎的销售额,其中255亿瑞士法郎归因于腕表销售。其中,四大独立奢侈腕表品牌ROLEX劳力士、PATEK PHILIPPE百达翡丽、AUDEMARS PIGUET爱彼和RICHARD MILLE理查米尔的市场份额增长到43.9%,与2019年新冠疫情前的36.9%相比,这种增长趋势尤其明显。 展开更多
关键词 摩根士丹利 钟表行业 瑞士法郎 rich 年度报告 腕表 劳力士
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Split Addition of Nitrogen-Rich Substrate at Thermophilic and Mesophilic Stages of Composting: Effect on Green House Gases Emission and Quality of Compost
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作者 Boakye Acheampong Kodwo Miezah +2 位作者 Enoch Bessah Benedicta Essel Ayamba Francis Kemausour 《Open Journal of Soil Science》 2024年第2期133-158,共26页
Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed ... Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH<sub>4</sub>, CO<sub>2</sub>, N<sub>2</sub>O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO<sub>2</sub> was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH<sub>4</sub> was highest in the mesophilic stage with N-rich substrate addition. N<sub>2</sub>O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost. 展开更多
关键词 COMPOST Nitrogen-rich Substrate THERMOPHILIC MESOPHILIC Greenhouse Gas Emissions
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Optimizing band structure of CoP nanoparticles via rich-defect carbon shell toward bifunctional electrocatalysts for overall water splitting 被引量:7
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作者 Juncheng Wu Zhe‐Fan Wang +7 位作者 Taotao Guan Guoli Zhang Juan Zhang Jie Han Shengqin Guan Ning Wang Jianlong Wang Kaixi Li 《Carbon Energy》 SCIE CSCD 2023年第3期112-125,共14页
Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of... Transition-metal phosphides(TMPs)with high catalytic activity are widely used in the design of electrodes for water splitting.However,a major challenge is how to achieve the trade-off between activity and stability of TMPs.Herein,a novel method for synthesizing CoP nanoparticles encapsu-lated in a rich-defect carbon shell(CoP/DCS)is developed through the self-assembly of modified polycyclic aromatic molecules.The graft and removal of high-activity C-N bonds of aromatic molecules render the controllable design of crystallite defects of carbon shell.The density functional theory calculation indicates that the carbon defects with unpaired electrons could effectively tailor the band structure of CoP.Benefiting from the improved activity and corrosion resistance,the CoP/DCS delivers outstanding difunctional hydrogen evolution reaction(88 mV)and oxygen evolution reaction(251 mV)performances at 10 mA cm^(−2)current density.Furthermore,the coupled water electrolyzer with CoP/DCS as both the cathode and anode presents ultralow cell voltages of 1.49 V to achieve 10 mA cm^(−2)with long-time stability.This strategy to improve TMPs electrocatalyst with rich-DCS and heterogeneous structure will inspire the design of other transition metal compound electrocatalysts for water splitting. 展开更多
关键词 band structure bifunctional electrocatalysts CoP nanoparticles overall water splitting rich‐defect carbon
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Platelet rich fibrin is not a barrier membrane!Or is it? 被引量:2
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作者 Amit Arvind Agrawal 《World Journal of Clinical Cases》 SCIE 2023年第11期2396-2404,共9页
Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier me... Platelet-rich fibrin(PRF)is widely used in dentistry and other fields of medicine,and its use has become popular in dental implantology.In several published studies,PRF has been used as a barrier membrane.A barrier membrane is a sheet of a certain material that acts as a biological and mechanical barrier against the invasion of cells that are not involved in bone formation,such as epithelial cells.Among the basic requirements of a'barrier membrane,occlusivity,stiffness,and space maintenance are the criteria that PRF primarily lacks;therefore,it does not fall under the category of barrier membranes.However,there is evidence that PRF membranes are useful in significantly improving wound healing.Does the PRF membrane act as a barrier?Should we think of adding or subtracting some points from the ideal requirements of a barrier membrane,or should we coin a new term or concept for PRF that will incorporate some features of a barrier membrane and be a combination of tissue engineering and biotechnology?This review is aimed at answering the basic question of whether the PRF membrane should be considered a barrier membrane or whether it is something more beyond the boundaries of a barrier membrane. 展开更多
关键词 Platelet rich fibrin Platelet rich plasma Barrier membrane Guided tissue regeneration Guided bone regeneration
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Platelet-rich plasma promotes peripheral nerve regeneration after sciatic nerve injury 被引量:3
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作者 Su-Long Wang Xi-Lin Liu +1 位作者 Zhi-Chen Kang Yue-Shu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期375-381,共7页
The effect of platelet-rich plasma on nerve regeneration remains controversial.In this study,we established a rabbit model of sciatic nerve small-gap defects with preserved epineurium and then filled the gaps with pla... The effect of platelet-rich plasma on nerve regeneration remains controversial.In this study,we established a rabbit model of sciatic nerve small-gap defects with preserved epineurium and then filled the gaps with platelet-rich plasma.Twenty-eight rabbits were divided into the following groups(7 rabbits/group):model,low-concentrati on PRP(2.5-3.5-fold concentration of whole blood platelets),medium-concentration PRP(4.5-6.5-fold concentration of whole blood platelets),and high-concentration PRP(7.5-8.5-fold concentration of whole blood platelets).Electrophysiological and histomorphometrical assessments and proteomics analysis we re used to evaluate regeneration of the sciatic nerve.Our results showed that platelet-rich plasma containing 4.5-6.5-and 7.5-8.5-fold concentrations of whole blood platelets promoted repair of sciatic nerve injury.Proteomics analysis was performed to investigate the possible mechanism by which platelet-rich plasma promoted nerve regeneration.Proteomics analysis showed that after sciatic nerve injury,platelet-rich plasma increased the expression of integrin subunitβ-8(ITGB8),which participates in angiogenesis,and differentially expressed proteins were mainly enriched in focal adhesion pathways.Additionally,two key proteins,ribosomal protein S27 a(RSP27 a)and ubiquilin 1(UBQLN1),which were selected after protein-protein interaction analysis,are involved in the regulation of ubiquitin levels in vivo.These data suggest that platelet-rich plasma promotes peripheral nerve regeneration after sciatic nerve injury by affecting angiogenesis and intracellular ubiquitin levels. 展开更多
关键词 bioinformatic analysis ITGB8 leukocyte-platelet rich plasma nerve regeneration peripheral nerve injury platelet-rich plasma proteomic analysis sciatic nerve injury
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Premature thermal decomposition behavior of 3,4-dinitrofurazanfuroxan with certain types of nitrogen-rich compounds 被引量:1
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作者 Jiao Huang Ru-fang Peng Bo Jin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期102-110,共9页
3,4-Dinitrofurazanfuroxan(DNTF),as a high-energy-density material,features good thermal stability and wide applications.This study aimed to elucidate the thermal decomposition mechanism of DNTF combined with nitrogen-... 3,4-Dinitrofurazanfuroxan(DNTF),as a high-energy-density material,features good thermal stability and wide applications.This study aimed to elucidate the thermal decomposition mechanism of DNTF combined with nitrogen-rich compounds containing N-H.The thermal stabilities of DNTF and its hybrid systems were investigated using differential thermal analysis/thermogravimetry(TG),vacuum stability test,and accelerating rate calorimetry under isothermal,non-isothermal,and adiabatic conditions,respectively.Results showed that the thermal stability and thermal safety of DNTF significantly decreased after combining with nitrogen-rich compounds containing N-H.Calculation results showed that the activation energy of the DNTF hybrid systems was significantly lower than that of DNTF.The TGIR was used to monitor the generation of fugitive gases during the thermal decomposition of the DNTF/5-aminotetrazole(5-ATZ)hybrid.Moreover,the nitrogen-rich molecules containing N-H interacted extensively with DNTF,and this interaction accelerated the thermal degradation of DNTF. 展开更多
关键词 DNTF NeH rich Nitrogen compounds Advanced thermal decomposition peak
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Clinical Evaluation of Platelet Rich Growth Factors (PRGFS) in Treatment of Temporomandibular Joint Disc Displacement—Study Report
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作者 Lahaou Baladji Touré Oumar Ongoïba +2 位作者 Djibril Kassogué Wael Ahmed Elmohandes Elsaeed Mohamed Abdellatif 《Open Journal of Stomatology》 CAS 2023年第5期174-187,共14页
Objective: The aim of the study was to evaluate the effect of platelet rich growth factors (PRGFs) in treatment of temporomandibular joint disc displacement. Materials and Methods: The study subjects included 8 female... Objective: The aim of the study was to evaluate the effect of platelet rich growth factors (PRGFs) in treatment of temporomandibular joint disc displacement. Materials and Methods: The study subjects included 8 females having bilateral anterior disc displacement with reduction and 1 female having bilateral anterior disc displacement without reduction with the age range between 20 - 35 years. The process of obtaining PRGFs was carried out following the Anitua Technique. Results: Clinical parameters of Interincisal distance, Lateral excursion of mandible using digital caliper in millimeters and Visual Analogue Scale (VAS 0/10) for pain intensity score were used. All of these parameters were running through the intervals of two, four, and eight weeks till the end of the follow-up period at twenty-six weeks (six months). The participated patients showed the clinical improvement in the different clinical statuses such as interincisal distance;lateral excursion of mandible and Pain Score. Conclusion: the study reported early efficacy of PRGFs after the arthrocentesis of the joint in treatment of TMJ disc displacement, and according to our results, the injection of PRGFs could be a possible alternative treatment for patients who did not respond to standard treatment. 展开更多
关键词 Platelet rich Growth Factors Platelet rich Plasma Temporomandibular Joint
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Predicting impacts of climate change on the biogeographic patterns of representative species richness in Prydz Bay-Amery Ice Shelf
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作者 Yugui ZHU Shiyao ZHENG +6 位作者 Bin KANG Gabriel REYGONDEAU Yan SUN Qianshuo ZHAO Yunfeng WANG William W.L.CHEUNG Jiansong CHU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1504-1518,共15页
The research on the biological ecology of the Prydz Bay-Amery Ice Shelf in East Antarctica is inadequate under the increasing threat from climate change,especially for Antarctic fish and krill.The Dynamic Bioclimatic ... The research on the biological ecology of the Prydz Bay-Amery Ice Shelf in East Antarctica is inadequate under the increasing threat from climate change,especially for Antarctic fish and krill.The Dynamic Bioclimatic Envelope Model(DBEM)has been widely used in predicting the variation of species distribution and abundance in ocean and land under climate change;it can quantify the spatiotemporal changes of multi population under different climate emission scenarios by identifying the environmental preferences of species.The species richness and geographical pattern of six Antarctic representative species around Prydz Bay-Amery ice shelf were studied under RCP 8.5 and RCP 2.6 emission scenarios from 1970 to 2060 using Geophysical Fluid Dynamics Laboratory(GFDL),Institut Pierre Simon Laplace(IPSL),and Max Planck Institute(MPI)earth system models.The results showed that the species richness decreased as a whole,and the latitude gradient moved to the pole.The reason is that ocean warming,sea ice melting,and human activities accelerate the distribution changes of species biogeographical pattern,and the habitat range of krill,silverfish,and other organisms is gradually limited,which further leads to the change of species composition and the decrease of biomass.It is obvious that priority should be given to Prydz Bay-Amery ice shelf in the planning of Marine Protected Areas(MPAs)in East Antarctica. 展开更多
关键词 climate change species richness biogeographic pattern marine protected areas Prydz Bay-Amery Ice Shelf
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The Role of Leukocyte and Platelet-Rich Fibrin in Enhancing the Healing of Extraction Sockets: An Overview of the Literature
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作者 Yazan Alawneh Mahmoud Abu-Ta’a 《Open Journal of Stomatology》 2023年第3期97-105,共20页
Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regard... Introduction: Leukocyte and platelet-rich fibrin (L-PRF) is an emerging material in dentistry, however, there are controversies surrounding its effectiveness. Despite the amount of literature available, debates regarding its effect continue. This review aims to summarize and clarify the data surrounding the use of L-PRF in promoting the healing of extraction sockets, which may offer a better outcome for future treatments. Purpose: The purpose of this review is to evaluate the current literature on the use of L-PRF in promoting the healing of extraction sockets, and to provide a comprehensive overview of the available evidence. Methods: A comprehensive computer-based search of databases such as PubMed, Medline, and Cochrane Library was conducted. Results: The results of this review suggest that L-PRF has shown promise in promoting early healing of extraction sockets, but the evidence for its effectiveness over a longer period is limited. Conclusion: Although L-PRF has shown promising results in the early healing periods, its effectiveness over a longer healing period cannot be confirmed based on the available data. More clinical trials with standardized protocols and consistent measurement methods are needed to establish the role of L-PRF in enhancing the healing of extraction sockets. 展开更多
关键词 Leukocyte and Platelet rich Fibrin Extraction Sockets Hard Tissue Soft Tissue
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Assessing Forest Cover Distribution, Species Diversity, and Richness of the Buffer Zone for Strategic Forest Management Planning for Nimule National Park, South Sudan
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作者 Joseph Mayindo Mayele Augustine Lokule Bongo 《Open Journal of Ecology》 2023年第11期836-864,共29页
Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected ... Natural forest ecosystems play an essential role in the conservation of biodiversity of many plants and animals by providing them with habitat and suitable environments. Studies have shown that biodiversity-protected areas reduce the loss and degradation of natural habitats to various wild species of plants. This study examined the forest resources in five subzones by conducting tree/shrub species inventory to be able to develop an effective forest management plan for the Buffer Zone Forest Reserve for the sustainable conservation of flora and fauna of Nimule National Park. This is with the view to identify the main tree and shrub species;assess the composition, distribution, and abundance of various tree/shrub species;to determine the species diversity as well as the richness of these areas in terms of growth and performance where DBH and heights of trees/shrubs in the circular sample plots were measured. The results revealed the overall mean DBH and H of 13.83 cm and 6.61 m respectively. The highest number of trees was obtained in subzone B followed by D, while the least were found in subzone A. The overall mean tree/shrub density was 0.83 tons/ha. The mean total basal area and volume per hectare were 3252.74 m<sup>2</sup>/ha and 46,540.82 m<sup>3</sup>/ha respectively. The overall species abundance and distribution indicate Combretum spp, Cedrella spp., Grewia mollis, Acacia Sieberiana, Ziziphus abysinica, and Acacia seyal were the most dominant species, with over 12 species richness at the deposition side of the River Nile, 13 species at the western side of the Nile, the Administration site shows only 7 species, the lowland of Mt. Gordon show over 14 different species, whereas over 10 species were found on the top of Mt. Gordon. The overall mean diversity indices and evenness of H’, D, and E depicted 2.507, 0.871, and 0.840 respectively. These results yielded are relatively moderate. Therefore, conservation efforts are very necessary to improve and maintain the quality of vegetation cover. 展开更多
关键词 Species Diversity Species Abundance Species richness Buffer Zone Nimule National Park South Sudan
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Optimization of operational strategies for rich gas enhanced oil recovery based on a pilot test in the Bakken tight oil reservoir
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作者 Xincheng Wan Lu Jin +4 位作者 Nicholas A.Azzolina Jin Zhao Xue Yu Steven A.Smith James A.Sorensen 《Petroleum Science》 SCIE EI CSCD 2023年第5期2921-2938,共18页
Horizontal well drilling and multistage hydraulic fracturing have been demonstrated as effective approaches for stimulating oil production in the Bakken tight oil reservoir.However,after multiple years of production,p... Horizontal well drilling and multistage hydraulic fracturing have been demonstrated as effective approaches for stimulating oil production in the Bakken tight oil reservoir.However,after multiple years of production,primary oil recovery in the Bakken is generally less than 10%of the estimated original oil in place.Gas huff‘n’puff(HnP)has been tested in the Bakken Formation as an enhanced oil recovery(EOR)method;however,most field pilot test results showed no significant incremental oil production.One of the factors affecting HnP EOR performance is premature gas breakthrough,which is one of the most critical issues observed in the field because of the presence of interwell fractures.Consequently,injected gas rapidly reaches adjacent production wells without contacting reservoir rock and increasing oil recovery.Proper conformance control is therefore needed to avoid early gas breakthrough and improve EOR performance.In this study,a rich gas EOR pilot in the Bakken was carefully analyzed to collect the essential reservoir and operational data.A simulation model with 16 wells was then developed to reproduce the production history and predict the EOR performance with and without conformance control.EOR operational strategies,including single-and multiple-well HnP,with different gas injection constraints were investigated.The simulation results of single-well HnP without conformance control showed that a rich gas injection rate of at least 10 MMscfd was needed to yield meaningful incremental oil production.The strategy of conformance control via water injection could significantly improve oil production in the HnP well,but injecting an excessive amount of water also leads to water breakthrough and loss of oil production in the offset wells.By analyzing the production performance of the wells individually,the arrangement of wells was optimized for multiple-well HnP EOR.The multiwell results showed that rich gas EOR could improve oil production up to 7.4%by employing conformance control strategies.Furthermore,replacing rich gas with propane as the injection gas could result in 14%of incremental oil production. 展开更多
关键词 rich gas injection Bakken tight oil reservoir EOR strategies Conformance control Embedded discrete fracture model
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RICE TO RICHES: BUILDING A GLOBAL COMMUNITY THE CHINESE WAY
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作者 Robert Walker 《China Report ASEAN》 2023年第12期64-64,共1页
China feeds a fifth of the world’s population from only one tenth of the world’s arable land.The need to feed its population has always been a concern of China’s rulers.As early as the Tang(618-907)and Song(960-127... China feeds a fifth of the world’s population from only one tenth of the world’s arable land.The need to feed its population has always been a concern of China’s rulers.As early as the Tang(618-907)and Song(960-1279)dynasties,the imperial government was encouraging people to expand food production beyond the fertile lowlands into the mountains. 展开更多
关键词 MOUNTAINS ARABLE rich
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东昆仑大格勒地区富铌橄榄岩矿物学、地球化学及Sr-Nd同位素特征 被引量:4
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作者 李积清 王涛 +7 位作者 王秉璋 李五福 王泰山 薛万文 李玉龙 李青 金婷婷 袁博武 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第1期114-124,共11页
东昆仑大格勒地区碳酸岩-碱性杂岩富铌稀土矿化的发现,对青海省优质稀有稀土矿产的勘查及综合研究具有重要启示。本文以大格勒杂岩体中蛇纹石化富铌橄榄岩为研究对象,开展了矿物学、岩石地球化学和Sr-Nd同位素研究。矿物学分析显示,富... 东昆仑大格勒地区碳酸岩-碱性杂岩富铌稀土矿化的发现,对青海省优质稀有稀土矿产的勘查及综合研究具有重要启示。本文以大格勒杂岩体中蛇纹石化富铌橄榄岩为研究对象,开展了矿物学、岩石地球化学和Sr-Nd同位素研究。矿物学分析显示,富铌橄榄岩中铌矿物主要为铌易解石(Nb_(2)O_(5)=50.33%~52.50%)、铌钙矿(Nb_(2)O_(5)=48.20%~50.27%)、褐铈铌矿(Nb_(2)O_(5)=42.80%~43.45%)、Stefanweissite矿(Nb_(2)O_(5)=33.14%~34.78%),次为钛铁矿(Nb_(2)O_(5)=3.45%~4.89%)。样品具低SiO_(2)(20.16%~29.20%)和K_(2)O+Na_(2)O(0.02%~2.47%)含量,高Mg O(22.88%~27.69%)含量和Mg^(#)值(74~82),稀土元素总量较高(∑REE=772~1807μg/g),稀土元素配分模式强烈富集LREE、亏损HREE,Eu异常不明显(δEu=0.87~1.17)。原始地幔标准化微量元素蛛网图显示,样品富集Nb、Ta、Th、U、Sr、Pb,Nb含量高,为981~1753μg/g,平均1378μg/g,可能与晚阶段碳酸岩侵入流体交代作用有关。样品的(87Sr/86Sr)i值为0.70378~0.70396,ε_(Nd)(t)值为-0.49~0.31,岩浆源区可能为EMⅠ型地幔端元。综合区域构造背景,大格勒岩体中富铌橄榄岩的形成可能与该地区拉张环境下岩石圈的强烈伸展和软流圈地幔的上涌相关。 展开更多
关键词 富铌橄榄岩 矿物化学 地球化学 SR-ND同位素 大格勒
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Facile construction of a multilayered interface for a durable lithium‐rich cathode
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作者 Zhou Xu Yifei Yuan +8 位作者 Qing Tang Xiangkun Nie Jianwei Li Qing Sun Naixuan Ci Zhenjie Xi Guifang Han Lijie Ci Guanghui Min 《Carbon Energy》 SCIE EI CAS CSCD 2023年第9期74-87,共14页
Layered lithium-rich manganese-based oxide(LRMO)has the limitation of inevitable evolution of lattice oxygen release and layered structure transformation.Herein,a multilayer reconstruction strategy is applied to LRMO ... Layered lithium-rich manganese-based oxide(LRMO)has the limitation of inevitable evolution of lattice oxygen release and layered structure transformation.Herein,a multilayer reconstruction strategy is applied to LRMO via facile pyrolysis of potassium Prussian blue.The multilayer interface is visually observed using an atomic-resolution scanning transmission electron microscope and a high-resolution transmission electron microscope.Combined with the electrochemical characterization,the redox of lattice oxygen is suppressed during the initial charging.In situ X-ray diffraction and the high-resolution transmission electron microscope demonstrate that the suppressed evolution of lattice oxygen eliminates the variation in the unit cell parameters during initial(de)lithiation,which further prevents lattice distortion during long cycling.As a result,the initial Coulombic efficiency of the modified LRMO is up to 87.31%,and the rate capacity and long-term cycle stability also improved considerably.In this work,a facile surface reconstruction strategy is used to suppress vigorous anionic redox,which is expected to stimulate material design in high-performance lithium ion batteries. 展开更多
关键词 lattice oxygen release lithium‐rich manganese‐based oxide cathodes reconstructed multilayer interface spinel phase transition‐metal ion migration
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Effect of Bismuth Subgallate/Borneol Combined with Autologous Platelet-Rich Gel in the Treatment of Patients with Diabetic Foot Ulcers 被引量:1
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作者 Qian Wen Ting Liu 《Journal of Biosciences and Medicines》 CAS 2023年第2期232-238,共7页
Objective: To explore the effect of Bismuth Subgallate/Borneol (Suile<sup>TM</sup> BSB) healing dressing combined with autologous platelet-rich gel (APG) in the treatment of diabetic foot ulcer (DFU). Meth... Objective: To explore the effect of Bismuth Subgallate/Borneol (Suile<sup>TM</sup> BSB) healing dressing combined with autologous platelet-rich gel (APG) in the treatment of diabetic foot ulcer (DFU). Methods: A total of 120 patients with DFU hospitalized in the Changsha Central Hospital from August 2020 to September 2021 were selected and randomly divided into an experimental group (BSB + APG, n = 60) and a control group (BSB, n = 60) according to random number table method. The total therapeutic effect, healing time, hospital stay, level indexes of various inflammatory factors before and after treatment and ulcer area were observed in the two groups. Results: The total effect of the control group was worse than that of the experimental group, and the data between the two groups were significant (P 0.05);after treatment, the levels of inflammatory factors including WBC, CRP, IL-6 and TNF-α in the control group were higher than those in the experimental group, and there was significant difference between the two groups (P 0.05);after 14 days of treatment, the ulcer area in the control group was larger than that in the experimental group, and the data between the two groups were significant (P Conclusion: BSB combined with APG can achieve better therapeutic effect, reduce the inflammatory reaction of patients, and promote wound healing in the treatment of patients with diabetic foot ulcer. 展开更多
关键词 Bismuth Subgallate/Borneol Autologous Platelet-rich Gel Diabetic Foot Ulcer Wound Healing
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