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Combined Promoting Effects of Specific Organic Functional Groups and Alumina Surface Characteristics for the Design of a Highly Efficient NiMo/Al_(2)O_(3) Hydrodesulfurization Catalyst 被引量:2
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作者 Li Huifeng Li Mingfeng +2 位作者 Zhang Le Wang Wei Nie Hong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期1-11,共11页
To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation betwe... To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation between the surface characteristics of four different alumina and the existing Mo species states was established.It was found that the Mo equilibrium adsorption capacity can be used as a specific descriptor to quantitatively evaluate the changes in surface characteristics of different alumina.A lower Mo equilibrium adsorption capacity for alumina means weaker metal-support interaction and the loaded Mo species are easier to transform into MoS2.However,the Mo-O-Al bonds still exist at the metal-support interface.The introduction of cationic surfactant hecadecyl trimethyl ammonium bromide(CTAB)can further improve Mo species dispersion through electrostatic attraction with Mo anions and interaction of its alkyl chain with the alumina surface;meanwhile,the introduction of ethylenediamine tetraacetic acid(EDTA)can complex with Ni ions to enhance the Ni-promoting effect on Mo.Therefore,the NiMo catalyst designed using alumina with lower Mo equilibrium adsorption capacity and the simultaneous addition of EDTA and CTAB exhibits the highest hydrodesulfurization activity for 4,6-dimethyl dibenzothiophene because of its proper metal-support interaction and more well-dispersed Ni-Mo-S active phases. 展开更多
关键词 ALUMINA Mo equilibrium adsorption capacity organic functional groups metal-support interaction HYDRODESULFURIZATION
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Covalent Bond Based Android Malware Detection Using Permission and System Call Pairs
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作者 Rahul Gupta Kapil Sharma R.K.Garg 《Computers, Materials & Continua》 SCIE EI 2024年第3期4283-4301,共19页
The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and... The prevalence of smartphones is deeply embedded in modern society,impacting various aspects of our lives.Their versatility and functionalities have fundamentally changed how we communicate,work,seek entertainment,and access information.Among the many smartphones available,those operating on the Android platform dominate,being the most widely used type.This widespread adoption of the Android OS has significantly contributed to increased malware attacks targeting the Android ecosystem in recent years.Therefore,there is an urgent need to develop new methods for detecting Android malware.The literature contains numerous works related to Android malware detection.As far as our understanding extends,we are the first ones to identify dangerous combinations of permissions and system calls to uncover malicious behavior in Android applications.We introduce a novel methodology that pairs permissions and system calls to distinguish between benign and malicious samples.This approach combines the advantages of static and dynamic analysis,offering a more comprehensive understanding of an application’s behavior.We establish covalent bonds between permissions and system calls to assess their combined impact.We introduce a novel technique to determine these pairs’Covalent Bond Strength Score.Each pair is assigned two scores,one for malicious behavior and another for benign behavior.These scores serve as the basis for classifying applications as benign or malicious.By correlating permissions with system calls,the study enables a detailed examination of how an app utilizes its requested permissions,aiding in differentiating legitimate and potentially harmful actions.This comprehensive analysis provides a robust framework for Android malware detection,marking a significant contribution to the field.The results of our experiments demonstrate a remarkable overall accuracy of 97.5%,surpassing various state-of-the-art detection techniques proposed in the current literature. 展开更多
关键词 andROID MALWARE android security hybrid analysis permission and system call pairs
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Generation of broadband polarization-orthogonal photon pairs via the dispersion-engineered thin-film lithium niobate waveguide
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作者 Ji-Ning Zhang Tong-Yu Zhang +2 位作者 Jia-Chen Duan Yan-Xiao Gong Shi-Ning Zhu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期46-51,共6页
Broadband photon pairs are highly desirable for quantum metrology,quantum sensing,and quantum communication.Such sources are usually designed through type-0 phase-matching spontaneous parametric down-conversion(SPDC)t... Broadband photon pairs are highly desirable for quantum metrology,quantum sensing,and quantum communication.Such sources are usually designed through type-0 phase-matching spontaneous parametric down-conversion(SPDC)that makes the photon pairs hard to separate in the frequency-degenerate case and thus limits their applications.In this paper,we design a broadband frequency-degenerate telecom-band photon pair source via the type-II SPDC in a dispersion-engineered thin-film lithium niobate waveguide,where the polarization modes of photon pairs are orthogonal and thus are easily separated deterministically.With a 5-mm-long waveguide,our design can achieve a bandwidth of 5.56 THz(44.8 nm),which is 8.6 times larger than that of the bulk lithium niobate,and the central wavelength can be flexibly adjusted.Our design is a promising approach towards high-quality integrated photon sources and may have wide applications in photonic quantum technologies. 展开更多
关键词 broadband photon pair source spontaneous parametric down-conversion dispersion engineering thin-film lithium niobate waveguide
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Introducing hydroxyl groups to tailor the d-band center of Ir atom through side anchoring for boosted ORR and HER
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作者 Qing Lv Meiping Li +3 位作者 Xiaodong Li Xingru Yan Zhufeng Hou Changshui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期144-151,I0005,共9页
Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of... Tuning the coordination atoms of central metal is an effective means to improve the electrocatalytic activity of atomic catalysts.Herein,iridium(Ir) is proposed to be asymmetrically anchored by sp-N and pyridinic N of hydrogen-substituted graphdiyne(HsGDY),and coordinated with OH as an Ir atomic catalyst(Ir_(1)-N-HsGDY).The electron structures,especially the d-band center of Ir atom,are optimized by these specific coordination atoms.Thus,the as-synthesized Ir_(1)-N-HsGDY exhibits excellent electrocatalytic performances for oxygen reduction and hydrogen evolution reactions in both acidic and alkaline media.Benefiting from the unique structure of HsGDY,IrN_(2)(OH)_(3) has been developed and demonstrated to act as the active site in these electrochemical reactions.All those indicate the fresh role of the sp-N in graphdiyne in producing a new anchor way and contributing to promote the electrocatalytic activity,showing a new strategy to design novel electrochemical catalysts. 展开更多
关键词 Oxygen reduction reaction D-band center Graphdiyne Hydroxyl group ELECTROCATALYSIS
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Overstory functional groups indicate the legacy of land use in a secondary tropical forest in southwestern China
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作者 Yun Deng Wenfu Zhang +9 位作者 Min Cao Jinlong Dong Hui Chen Xiaobao Deng Jiajia Liu Xiaoyang Song Shangwen Xia Liqing Sha Shengdong Yuan Luxiang Lin 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期91-105,共15页
Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due ... Anthropogenic disturbances are widespread in tropical forests and influence the species composition in the overstory.However,the impacts of historical disturbance on tropical forest overstory recovery are unclear due to a lack of disturbance data,and previous studies have focused on understory species.In this study,the purpose was to deter-mine the influence of historical disturbance on the diver-sity,composition and regeneration of overstory species in present forests.In the 20-ha Xishuangbanna tropical sea-sonal rainforest dynamics plot in southwestern China,the historical disturbance boundaries were delineated based on panchromatic photographs from 1965.Factors that drove species clustering in the overstory layer(DBH≥40 cm)were analyzed and the abundance,richness and composition of these species were compared among different tree groups based on multiple regression tree analysis.The coefficient of variation of the brightness value in historical panchro-matic photographs from 1965 was the primary driver of spe-cies clustering in the overstory layer.The abundance and richness of overstory species throughout the regeneration process were similar,but species composition was always different.Although the proportion of large-seeded and vigorous-sprouting species showed no significant differ-ence between disturbed and undisturbed forests in the tree-let layer(DBH<20 cm),the difference became significant when DBH increased.The findings highlight that historical disturbances have strong legacy effects on functional group composition in the overstory and the recovery of overstory species was multidimensional.Functional group composi-tion can better indicate the dynamics of overstory species replacement during secondary succession. 展开更多
关键词 Historical disturbance Legacy effects Secondary forests Overstory species Functional groups
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A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network
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作者 Shuyong Duan Jialin Zhang +2 位作者 Heng Ouyang Xu Han Guirong Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期215-228,共14页
On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness... On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material properties.This work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material parameters.The use of echo groups allows the use of lower frequencies,and hence more accommodative to structural complexity.To train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given structure.The waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical model.This results in a set of dataset for training the ANN model.Once the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the ANN.Intensive tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed method.The results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic constants.Moreover,the reliability and accuracy of inverse prediction is significantly improved.Thus,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment. 展开更多
关键词 Parameter identification Ultrasonic echo group High-precision modeling Artificial neural network NDT
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Highlighting relationships between sand thicknesses,reservoir-seal pairs and paleobathymetry from a sequence stratigraphic perspective:An example from Tortonian Serravallian deposits,onshore Niger Delta Basin
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作者 Ifeanyichukwu S.Obi K.Mosto Onuoha Chidozie I.Princeton Dim 《Energy Geoscience》 EI 2024年第1期12-23,共12页
The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challe... The utilization of sequence stratigraphic concepts in identifying sands and their spatial continuity in distinct gross depositional settings is key,especially in frontier settings where data paucity is a common challenge.In the Baka field,onshore Niger Delta,detailed reservoir correlation guided by sequence stratigraphic framework analysis showed the distribution of sand and shale units constituting reservoirseal pairs(RSP)correlatable across the field.Within the 3rd-order packages,it is observed that the lowstand systems tract(LST)and highstand systems tract(HST)contain more RSPs and thicker 4th-and 5th-order sands than the transgressive systems tract(TST).In terms of bathymetry,it is noted that irrespective of systems tracts,the RSP Index(RI)decreases from the proximal shallow/inner shelf settings to the more distal outer shelf areas.Amongst all three systems tracts,intervals interpreted as lowstand prograding complexes contain the best developed sands and highest RSP.Sand development within the LSTs has been controlled by a pronounced growth fault regime accompanied by high subsidence and sedimentation rates.This is linked to the basinward migration of the sands during prolonged sea-level fall,creating significant accommodation space for sand deposition.On the other hand,the TSTs known to mark periods of progressive sea-level rise and landward migration of sandy facies,show thinner sands enclosed in much thicker,laterally extensive,and better-preserved deeper marine shales.Interpreted seismic sections indicate intense growth faulting and channelization that influenced the syn-and postdepositional development of the sand packages across the field.The initial timing of deformation of subregional faults in this area coincides with periods of abrupt falls in sea level.This approach could be useful for predicting sand-prone areas in frontier fields as well as possible reservoir-seal parameters required for some aspects of petroleum system analysis and quick-look volume estimation. 展开更多
关键词 Reservoir-seal pairs(RSP) Systems tract Coastal swamp depobelt Bathymetry Sequence stratigraphy Niger Delta Basin
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Role of self-help groups on socioeconomic development and the achievement of Sustainable Development Goals(SDGs)among rural women in Cooch Behar District,India
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作者 Debanjan BASAK Indrajit Roy CHOWDHURY 《Regional Sustainability》 2024年第2期63-74,共12页
This study examines the transformative role of self-help groups(SHGs)in the socioeconomic development of rural women in Cooch Behar District,India,and their contribution toward achieving Sustainable Development Goals(... This study examines the transformative role of self-help groups(SHGs)in the socioeconomic development of rural women in Cooch Behar District,India,and their contribution toward achieving Sustainable Development Goals(SDGs)of the United Nations.In this study,we explored the effect of SHGs on rural women by specifically addressing SDGs,such as no poverty(SDG 1),zero hunger(SDG 2),good health and well-being(SDG 3),quality education(SDG 4),and gender equality(SDG 5).Given this issue,a cross-sectional survey and comparison analyses are needed to assess the socioeconomic development of rural women and their awareness level before and after the participation of rural women in SHGs.The survey conducted as part of this study was divided into three sections,namely,demographic characteristics,socioeconomic development,and awareness level,with each focusing on different aspects.A group of 400 individuals who were part of SHGs completed the questionnaire survey form.The results showed that the participation of rural women in SHGs significantly improved their socioeconomic development and awareness level,as supported by both mean values and t test results.Memberships in SHGs and microcredit programs were the major elements that boosted the socioeconomic development of rural women,which also achieves SDGs 1,2,3,4,and 5.This study revealed that participation in SHGs and related financial services significantly aided rural women in economically disadvantaged communities in accumulating savings and initiating entrepreneurial ventures.Moreover,participation in SHGs was instrumental in enhancing the self-confidence,self-efficacy,and overall self-esteem of rural women.Finally,doing so enabled them to move more freely for work and other activities and to make family and common decisions. 展开更多
关键词 Self-help groups Rural women SOCIOECONOMIC development Sustainable Development Goals(SDGs) MICROCREDIT INDIA
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Iran-Turkmenistan Relations:Cross-Border Ethnic Groups and Comprehensive Governance Strategies
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作者 WU Tongyu 《International Relations and Diplomacy》 2024年第5期181-190,共10页
This study delves into the bilateral relations between Iran and Turkmenistan,focusing on the multidimensional impacts of cross-border ethnic groups,cultural diplomacy,and energy cooperation.The research reveals that d... This study delves into the bilateral relations between Iran and Turkmenistan,focusing on the multidimensional impacts of cross-border ethnic groups,cultural diplomacy,and energy cooperation.The research reveals that despite challenges in security cooperation,such as regional political ideological differences and uneven power distribution,Iran has adopted diverse strategies to enhance cultural identity,social cohesion,and promote economic cooperation.Iran actively seeks to repair relations with Turkmenistan by emphasizing shared historical and cultural backgrounds,particularly the presence of cross-border Turkmen ethnic groups.Specific measures include developing cultural tourism,organizing cultural weeks,and establishing commemorative days.In the economic sphere,the two countries have signed significant natural gas supply agreements,strengthening energy cooperation.Iranian leaders often emphasize“blood ties”and deep cultural connections in diplomatic statements,combining cultural diplomacy with practical economic cooperation.The study’s findings indicate that Iran’s initiatives have led to the reorganization of national space and social reconstruction in border regions,promoting changes in public policy.By integrating cultural identity,historical connections,and economic interests,Iran has adopted a sophisticated diplomatic approach,laying the foundation for more stable and enduring bilateral relations while contributing to regional stability and sustainable development. 展开更多
关键词 Iranian foreign policy cross-border ethnic groups Iran-Turkmenistan relations
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The Influence of Depression on Different Age and Gender Groups in Bahawalpur
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作者 Mehran Khan Muhammad Shahbaz +7 位作者 Tooba Waris Shoaib Yaseen Iqra Afzal Emaan Khadim Sawera Usman Muhammad Ismail Shah Sulaiman Aslam Zafar Iqbal 《Journal of Clinical and Nursing Research》 2024年第7期196-207,共12页
In Bahawalpur,a cross-sectional study assessed depression prevalence across age and gender groups,involving 442 participants from diverse socioeconomic backgrounds and settings.Utilizing the PHQ9 questionnaire,84%were... In Bahawalpur,a cross-sectional study assessed depression prevalence across age and gender groups,involving 442 participants from diverse socioeconomic backgrounds and settings.Utilizing the PHQ9 questionnaire,84%were found to meet depression levels.The findings revealed a higher incidence in females(88%)than males(79%),with the greatest disparity among young adults,particularly young women,due to factors like academic pressure and financial stress.School children had the lowest depression rates(68%),possibly due to better immunity.Elderly individuals exhibited more severe depression,likely related to aging and domestic challenges.The study’s findings highlight a significant variation in depression severity across different demographic groups,with an overall higher incidence in women.The research underscores the necessity for targeted mental health resources and interventions tailored to the specific needs of each demographic group.It also points to the importance of addressing academic and socioeconomic stressors to mitigate depression,particularly among young women.While the study provides valuable insights,it relies on self-reported data,which may introduce bias.Therefore,future research should include clinical assessments to validate these findings and ensure a more accurate representation of depression within the community. 展开更多
关键词 Influence DEPRESSION Different age Gender groups Bahawalpur
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Surgical treatment of liver cancer and pancreatic cancer under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Fan Yu +1 位作者 Yu-Zhuo Zhou Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第21期4673-4679,共7页
BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers account... BACKGROUND Data from the World Health Organization’s International Agency for Research on Cancer reported that China had the highest prevalence of cancer and cancer deaths in 2022.Liver and pancreatic cancers accounted for the highest number of new cases.Real-world data(RWD)is now widely preferred to traditional clinical trials in various fields of medicine and healthcare,as the traditional research approach often involves highly selected populations and interventions and controls that are strictly regulated.Additionally,research results from the RWD match global reality better than those from traditional clinical trials.AIM To analyze the cost disparity between surgical treatments for liver and pancreatic cancer under various factors.METHODS This study analyzed RWD 1137 cases within the HB1 group(patients who underwent pancreatectomy,hepatectomy,and/or shunt surgery)in 2023.It distinguished different expenditure categories,including medical,nursing,technical,management,drug,and consumable costs.Additionally,it assessed the contribution of each expenditure category to total hospital costs and performed cross-group comparisons using the non-parametric Kruskal–Wallis test.This study used the Steel–Dwass test for post-hoc multiple comparisons and the Spearman correlation coefficient to examine the relationships between variables.RESULTS The study found that in HB11 and HB13,the total hospitalization costs were significantly higher for pancreaticoduodenectomy than for pancreatectomy and hepatectomy.Although no significant difference was observed in the length of hospital stay between patients who underwent pancreaticoduodenectomy and pancreatectomy,both were significantly longer than those who underwent liver resection.In HB15,no significant difference was observed in the total cost of hospitalization between pancreaticoduodenectomy and pancreatectomy;however,both were significantly higher than those in hepatectomy.Additionally,the length of hospital stay was significantly longer for patients who underwent pancreaticoduodenectomy than for those who underwent pancreatectomy or liver resection.CONCLUSION China Healthcare Security Diagnosis Related Groups payment system positively impacts liver and pancreatic cancer surgeries by improving medical quality and controlling costs.Further research could refine this grouping system and ensure continuous effectiveness and sustainability. 展开更多
关键词 China health care security diagnosis-related groups Real-world study Liver cancer surgical treatment Pancreatic cancer surgical treatment Hospitalization costs Cost structure Average length of stay
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Stabilizing Buried Interface via Synergistic Effect of Fluorine and Sulfonyl Functional Groups Toward Efficient and Stable Perovskite Solar Cells 被引量:2
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作者 Cheng Gong Cong Zhang +4 位作者 Qixin Zhuang Haiyun Li Hua Yang Jiangzhao Chen Zhigang Zang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第2期32-45,共14页
The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further en... The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further enhancement of the photovoltaic performance of the devices using sequential deposition.Herein,a buried interface stabilization strategy that relies on the synergy of fluorine(F)and sulfonyl(S=O)functional groups is proposed.A series of potassium salts containing halide and non-halogen anions are employed to modify SnO_(2)/perovskite buried interface.Multiple chemical bonds including hydrogen bond,coordination bond and ionic bond are realized,which strengthens interfacial contact and defect passivation effect.The chemical interaction between modification molecules and perovskite along with SnO_(2) heightens incessantly as the number of S=O and F augments.The chemical interaction strength between modifiers and perovskite as well as SnO_(2) gradually increases with the increase in the number of S=O and F.The defect passivation effect is positively correlated with the chemical interaction strength.The crystallization kinetics is regulated through the compromise between chemical interaction strength and wettability of substrates.Compared with Cl−,all non-halogen anions perform better in crystallization optimization,energy band regulation and defect passivation.The device with potassium bis(fluorosulfonyl)imide achieves a tempting efficiency of 24.17%. 展开更多
关键词 Perovskite solar cells Buried interface Multiple chemical bonds Synergistic effect of functional groups Defect passivation
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Eff ects of stand condition and root density on fi ne-root dynamics across root functional groups in a subtropical montane forest 被引量:1
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作者 Lin Huang Rudong Zhao +3 位作者 Xiaoxiang Zhao Qiuxiang Tian Pengyun Yue Feng Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期665-675,共11页
Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-bas... Fine roots play key roles in belowground C cycling in terrestrial ecosystems.Based on their distinct functions,fi ne roots are either absorptive fi ne roots(AFRs)or transport fi ne roots(TFRs).However,the function-based fi ne root dynamics of trees and their responses to forest stand properties remain unclear.Here,we studied the dynamics of AFRs and TFRs and their responses to stand conditions and root density in a subtropical montane mixed forest based on a 2-a root window experiment.Mean(±SE)annual production,mortality,and turnover rate of AFRs were 7.87±0.17 m m^(−2)a^(−1),8.13±0.20 m m^(−2)a^(−1)and 2.96±0.24 a^(−1),respectively,compared with 7.09±0.17 m m^(−2)a^(−1),4.59±0.17 m m^(−2)a^(−1),and 2.01±0.22 a^(−1),respectively,for TFRs.The production and mortality of fi ne roots were signifi cantly higher in high root-density sites than in low-root density sites,whereas the turnover of fi ne roots was faster in the low root-density sites.Furthermore,root density had a larger positive eff ect than other environmental factors on TFR production but had no obvious impact on AFR production.Tree species diversity had an apparent positive eff ect on AFR production and was the crucial driver of AFR production,probably due to a complementary eff ect,but had no evident impact on TFR.Both tree density and tree species diversity were positively correlated with the mortality of AFRs and negatively related to the turnover of TFRs,suggesting that higher root density caused stronger competition for rooting space and that plants tend to reduce maintenance costs by decreasing TFR turnover.These fi ndings illustrated the importance of root functional groups in understanding root dynamics and their responses to changes in environmental conditions. 展开更多
关键词 Root functional group Root production Root mortality Root turnover Stand condition Badagongshan mountain
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Normal and Superconducting Properties of La_(3)Ni_(2)O_(7) 被引量:1
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作者 王猛 闻海虎 +2 位作者 吴涛 姚道新 向涛 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期140-151,共12页
This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high press... This review provides a comprehensive overview of current research on the structural,electronic,and magnetic characteristics of the recently discovered high-temperature superconductor La_(3)Ni_(2)O_(7) under high pressures.We present the experimental results for synthesizing and characterizing this material,derived from measurements of transport,thermodynamics,and various spectroscopic techniques,and discuss their physical implications.We also explore theoretical models proposed to describe the electronic structures and superconducting pairing symmetry in La_(3)Ni_(2)O_(7),highlighting the intricate interplay between electronic correlations and magnetic interactions.Despite these advances,challenges remain in growing high-quality samples free of extrinsic phases and oxygen deficiencies and in developing reliable measurement tools for determining diamagnetism and other physical quantities under high pressures.Further investigations in these areas are essential to deepening our understanding of the physical properties of La_(3)Ni_(2)O_(7) and unlocking its superconducting pairing mechanism. 展开更多
关键词 PAIRING ELECTRONIC DEEPENING
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Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review 被引量:5
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作者 Rui Han Anning Zhou +4 位作者 Ningning Zhang Kaiqiang Guo Mengyan Cheng Heng Chen Cuicui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期217-230,共14页
Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery a... Coal gasification fine slag(FS)is a typical solid waste generated in coal gasification.Its current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological hazards.Separation recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental benefits.The structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of FS-RC.In this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle size.The reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is summarized.Separation methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the future.The design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the future.The high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization method.This review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the efficient flotation separation of FS,and the expansion of the field of the high value-added utilization of FS-RC. 展开更多
关键词 coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization
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Network pharmacology and subsequent experimental validation reveal the synergistic myocardial protection mechanism of Salvia miltiorrhiza Bge.and Carthamus tinctorius L. 被引量:1
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作者 Linying Zhong Ling Dong +7 位作者 Jing Sun Jie Yang Zhiying Yu Ping He Bo Zhu Yuxin Zhu Siyuan Li Wenjuan Xu 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期44-54,共11页
Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and su... Objective:To reveal the molecular mechanism underlying the compatibility of Salvia miltiorrhiza Bge(S.miltiorrhiza,Dan Shen)and C.tinctorius L.(C.tinctorius,Hong Hua)as an herb pair through network pharmacology and subsequent experimental validation.Methods:Network pharmacology was applied to construct an active ingredient-efficacy target-disease protein network to reveal the unique regulation pattern of s.miltiorrhiza and C.tinctorius as herb pair.Molecular docking was used to verify the binding of the components of these herbs and their potential targets.An H9c2 glucose hypoxia model was used to evaluate the efficacy of the components and their synergistic effects,which were evaluated using the combination index.Western blot was performed to detect the protein expression of these targets.Results:Network pharmacology analysis revealed 5 pathways and 8 core targets of s.miltiorrhiza and C.tinctorius in myocardial protection.Five of the core targets were enriched in the hypoxia-inducible factor-1(HIF-1)signaling pathway.S.miltiorrhiza-C.tinctorius achieved vascular tone mainly by regulating the target genes of the HIF-1 pathway.As an upstream gene of the HIF-1 pathway,STAT3 can be activated by the active ingredients cryptotanshinone(Ctan),salvianolic acid B(Sal.B),and myricetin(Myric).Cell experiments revealed that Myric,Sal.B,and Ctan also exhibited synergistic myocardial protective activity.Molecular docking verified the strong binding of Myric,Sal.B,and Ctan to STAT3.Western blot further showed that the active ingredients synergistically upregulated the protein expressionof STAT3.Conclusion:The pharmacodynamic transmission analysis revealed that the active ingredients of S.miltiorrhiza and C.tinctorius can synergistically resist ischemia through various targets and pathways.This study provides a methodological reference for interpreting traditional Chinese medicine compatibility. 展开更多
关键词 S.miltiorrhiza-C.tinctorius herb pair Compatibilitymechanism Networkpharmacology Multipletargeteffect Myocardial protection
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Functional groups and seasonal diversity of crustacean zooplankton in adjacent waters of Haizhou Bay,South Yellow Sea
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作者 Zeqi ZHENG Shunan FU +5 位作者 Yixuan LI Ruping GE Hongju CHEN Zhenjiang YE Yunyun ZHUANG Guangxing LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1007-1023,共17页
Zooplankton are important linkages in the food web and can respond nonlinearly to environmental changes.Marine organisms thrive from spring to summer.Thus,it is crucial to understand how ecological functions of zoopla... Zooplankton are important linkages in the food web and can respond nonlinearly to environmental changes.Marine organisms thrive from spring to summer.Thus,it is crucial to understand how ecological functions of zooplankton communities may shift under seasonal environmental changes during this period.Samples were collected from May to August(May,June-Ⅰ,June-Ⅱ,July-Ⅰ,July-Ⅱ,and August)in 2018 in Haizhou Bay,Jiangsu,East China for zooplankton and environmental variables.Crustaceans accounted for 75 out of 134 zooplankton taxa and 91.8%of total zooplankton abundance.The average abundance of crustacean varied between 2824.6±635.4 inds./m3 in July-Ⅱand 6502.7±1008.8 inds./m3 in June-Ⅱ.Multivariate analyses results showed that the dissimilarity of community increased gradually in the time series.Body length,feeding type,trophic group,and reproduction mode were used to investigate crustacean community functions.Trait-based functional groups contained species with similar ecological roles.Functional diversity fused the differences of species and trait.The proportion of large-sized species(2-5 mm)decreased with the increasing proportion of medium-sized species(1-2 mm).The proportion of current feeders increased with the drop in the proportion of mixed feeders.Parthenogenesis species increased with decreasing free spawners,and omnivores-carnivores increased with decreasing omnivoresherbivores.Generalized additive models suggested that temperature was the main driver of variations in crustacean zooplankton function.Seven identified functional groups varied with increasing temperature.Omnivorous-herbivorous copepods declined(90.0%-68.0%),whereas the parthenogenetic cladocerans increased(0-24.1%).The small egg-brooding ambush copepods fluctuated(6.5%-9.3%)with increasing water temperature.The other functional groups changed slightly.Functional diversity also varied according to temperature changes.The community structure and ecological function of crustacean zooplankton community showed gradual changes with increasing temperature from spring to summer. 展开更多
关键词 ZOOPLANKTON TRAIT functional group DIVERSITY Yellow Sea Haizhou Bay
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Colorectal cancer screening: Modalities and adherence 被引量:1
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作者 Georgios Metaxas Athena Papachristou Martha Stathaki 《World Journal of Gastroenterology》 SCIE CAS 2024年第24期3048-3051,共4页
In the last decade,several studies have explored various modalities and strategies for colorectal cancer(CRC)screening,taking into account epidemiological data,individual characteristics,and socioeconomic factors.In t... In the last decade,several studies have explored various modalities and strategies for colorectal cancer(CRC)screening,taking into account epidemiological data,individual characteristics,and socioeconomic factors.In this editorial,we comment further on a retrospective study by Agatsuma et al published in the recent issue of the World Journal of Gastroenterology.Our focus is on screening trends,particularly in relation to efforts to improve the currently suboptimal uptake among the general population worldwide,aiming to enhance early diagnosis rates of CRC.There is a need to raise awareness through health edu-cation programs and to consider the use of readily available,non-invasive screening methods.These strategies are crucial for attracting screen-eligible populations to participate in first-line screening,especially those in high-or average-risk groups and in regions with limited resources.Liquid biopsies and biomarkers represent rapidly evolving trends in screening and diagnosis;however,their clinical relevance has yet to be standardized. 展开更多
关键词 Colorectal cancer Screening test High-risk group Strategies BIOMARKER Liquid biopsy Screening adherence
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Step‑by‑Step Modulation of Crystalline Features and Exciton Kinetics for 19.2%Efficiency Ortho‑Xylene Processed Organic Solar Cells 被引量:1
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作者 Bosen Zou Weiwei Wu +10 位作者 Top Archie Dela Pena Ruijie Ma Yongmin Luo Yulong Hai Xiyun Xie Mingjie Li Zhenghui Luo Jiaying Wu Chuluo Yang Gang Li He Yan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期258-272,共15页
With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.... With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.However,previous studies are heavily based in chloroform(CF)leaving behind substantial knowledge deficiencies in understanding the influence of solvent choice when introducing a third component.Herein,we present a case where a newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy,named BTP-BO-3FO with enlarged bandgap,brings different morphological evolution and performance improvement effect on host system PM6:BTP-eC9,processed by CF and ortho-xylene(o-XY).With detailed analyses supported by a series of experiments,the best PCE of 19.24%for green solvent-processed OSCs is found to be a fruit of finely tuned crystalline ordering and general aggregation motif,which furthermore nourishes a favorable charge generation and recombination behavior.Likewise,over 19%PCE can be achieved by replacing spin-coating with blade coating for active layer deposition.This work focuses on understanding the commonly met yet frequently ignored issues when building ternary blends to demonstrate cutting-edge device performance,hence,will be instructive to other ternary OSC works in the future. 展开更多
关键词 Organic solar cells Ternary design Solvent selection Flouro-methoxylated end group Morphological ordering
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Partial Groups, Simplicial K(G, 1)’s and Kan Complexes
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作者 Solomon Jekel 《Advances in Pure Mathematics》 2023年第11期725-731,共7页
In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the... In our paper Simplicial K(G, 1)’s we constructed a sub-complex of the nerve of a group G determined by a partial group structure, and we proved, under a generalized associativity condition called regularity, that the sub-complex realizes as a K(G, 1). This type of sub-complex appears naturally in several topological and algebraic contexts. In this note we prove that regularity of a partial group implies that the Kan extension condition is satisfied on its nerve in dimensions greater than one, and in dimension one a weaker version of the extension condition holds. 展开更多
关键词 Partial Group Simplicial Set NERVE Kan Extension
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