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GENERALIZED COUNTING FUNCTIONS AND COMPOSITION OPERATORS ON WEIGHTED BERGMAN SPACES OF DIRICHLET SERIES
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作者 Min HE Maofa WANG Jiale CHEN 《Acta Mathematica Scientia》 2025年第2期291-309,共19页
In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditio... In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditions for a composition operator with zero characteristic to be bounded or compact on weighted Bergman spaces of Dirichlet series.The corresponding sufficient condition for compactness in the case of positive characteristics is also obtained. 展开更多
关键词 generalized counting function Dirichlet series composition operator weighted Bergman space
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Generalized multiple-mode prolate spheroidal wave functions multi-carrier waveform with index modulation
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作者 XU Zhichao LU Faping +5 位作者 ZHANG Lifan YANG Dongkai LIU Chuanhui KANG Jiafang AN Qi ZHANG Zhilin 《Journal of Systems Engineering and Electronics》 2025年第2期311-322,共12页
A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The p... A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The proposed method,based on the optimized multi-index modulation, does not limit the number of signals in the first and second constellations and abandons the concept of limiting the number of signals in different constellations. It successfully increases the spectrum efficiency of the system while expanding the number of modulation symbol combinations and the index dimension of PSWFs signals. The proposed method outperforms the PSWFs multi-carrier index modulation method based on optimized multiple indexes in terms of spectrum efficiency, but at the expense of system computational complexity and bit error performance. For example, with n=10 subcarriers and a bit error rate of 1×10^(-5),spectral efficiency can be raised by roughly 12.4%. 展开更多
关键词 prolate spherical wave function(PSWF) generalized multiple-mode index modulation spectral efficiency.
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Effects of gastrointestinal motility therapy combined with acupuncture on gastrointestinal function in patients after laparoscopic radical surgery
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作者 Chen Liang Feng-Xi Qiu +1 位作者 Xiao-Cun Zhang Qi-Long Hu 《World Journal of Gastrointestinal Surgery》 2025年第6期125-134,共10页
BACKGROUND Gastrointestinal(GI)dysfunction is common after laparoscopic radical gastrectomy for gastric cancer and affects rehabilitation.While conventional treatments can alleviate symptoms to a certain extent,they o... BACKGROUND Gastrointestinal(GI)dysfunction is common after laparoscopic radical gastrectomy for gastric cancer and affects rehabilitation.While conventional treatments can alleviate symptoms to a certain extent,they often fail to fully address the issue of insufficient GI motility.The GI motility therapeutic apparatus promotes dynamic recovery by simulating GI electric waves,whereas acupuncture regulates zang-fu qi movement,both offering effective interventions.However,there are few clinical studies investigating the combined use of GI motility therapy and acupuncture to promote GI function recovery in patients after GI laparoscopic radical surgery.AIM To evaluate the effects of combining GI motility therapy devices with acupuncture on GI function in patients undergoing radical laparoscopic surgery.METHODS This retrospective study included 196 patients who underwent radical GI endoscopic surgery at the Shanghai Yangzhi Rehabilitation Hospital(Shanghai Sunshine Rehabilitation Center),School of Medicine,Tongji University,from June 2022 to May 2024.Patients were classified into a normal group(conventional treatment,n=96)and an integrated group(conventional+GI motility therapy device+acupuncture,n=100).The effects on GI function,hormone levels preand post-treatment,GI symptoms,immune function,adverse reactions,and patient satisfaction in both groups were assessed.RESULTS Compared with the normal group,the integrated group demonstrated significantly better overall effectiveness(93.00%vs 84.3%;P<0.05)and shorter durations for first exhaust,feeding,defecation,and hospital stay(P<0.05).Post-treatment,the integrated group had lower gastrin and GI symptom rating scale scores and higher motilin,vasoactive intestinal peptide,and immune marker(CD3+,CD4+,CD4+/CD8+,and natural killer cells)levels(P<0.05).The integrated group,compared to the normal group,also reported fewer adverse reactions(5.00%vs 14.58%)and higher patient satisfaction(97.00%vs 84.38%),both statistically significant(P<0.05).CONCLUSION The combination of a GI motility therapy device and acupuncture promotes GI function recovery after radical gastrectomy,regulates GI hormones and immune function,and is safe and effective. 展开更多
关键词 Laparoscopic radical surgery Gastrointestinal functional disorders Gastrointestinal motility therapy device Acupuncture therapy Zusanli acupoint Curative effect
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Association between Neutrophil-to-lymphocyte Ratio and Renal Function:A Cross-sectional Study with Threshold Effects
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作者 Lin Hu Mingcong Chen +3 位作者 Qiuwei Tian Zisai Wang Mingyi Zhao Qingnan He 《Biomedical and Environmental Sciences》 2025年第11期1458-1462,共5页
Chronic kidney disease(CKD)is a recognized global public health burden affecting over 15%of the general population[1].By 2040,CKD is expected to become the fifth-leading cause of death in the world[2].The neutrophil-t... Chronic kidney disease(CKD)is a recognized global public health burden affecting over 15%of the general population[1].By 2040,CKD is expected to become the fifth-leading cause of death in the world[2].The neutrophil-to-lymphocyte ratio(NLR)indicates local or systemic inflammation status.The NLR has been demonstrated to exhibit predictive value in various pathological conditions,including—but not limited to—pancreatic cancer,as well as macrovascular and microvascular diseases,and sepsis[3,4]. 展开更多
关键词 chronic kidney disease neutrophil lymphocyte ratio INFLAMMATION chronic kidney disease ckd public health burden threshold effects renal function
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Functional evaluation for effective compositions in seed oil of Korean pine 被引量:14
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作者 王振宇 陈小强 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期215-217,共3页
The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were ra... The effect of seed oil of Korean pine (Pinus koraiensis) on the rats' blood-fat and its anti-ageing function was stud-ied for appraising the efficacy of the seed oil of Korean pine. Sixty experimental rats were randomly divided into 5 groups (half males and half females in each group) as normal control group, high fat diet control group, and three groups (Group 1 Group 2, Group 3) that were fed with feedstuff with the contents of the seed oil of 2.0g/(kgd-1), 4.0g/(kgd-1) and 8.0g/(kgd-1), respec-tively. The indexes such as superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and anti-oxidation capacity (AOC) were measured by Reagent Kit method. It was found that the seed oil of the Korean pine could reduce the content of triglyc-eride and improve SOD as well as GSH-PX activity in serum. These indexes of the rats in Group 2 fed with Korean pine seed oil of 4.0 g/(kgd-1) reached the significant level and those of rats in Group 3 fed with the seed oil of 8.0 g/(kgd-1) reached the extremely significant level. The results indicated the seed oil of Korean pine had function of regulating the level of blood-fat and anti-ageing. 展开更多
关键词 Korean pine seed oil effective compositions functional evaluation Blood-fat ANTI-AGEING
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Study of the generalized mixture rule for determining effective conductivity of two-phase stochastic models 被引量:1
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作者 余勇 吴小平 《Applied Geophysics》 SCIE CSCD 2010年第3期210-216,292,共8页
The generalized mixture rule (GMR) is usually applied in determining mechanical properties such as the rheological property and Young’s modulus of multi-phase rocks. However, it is rarely used to determine electric... The generalized mixture rule (GMR) is usually applied in determining mechanical properties such as the rheological property and Young’s modulus of multi-phase rocks. However, it is rarely used to determine electrical conductivity of multi-phase rocks presently. In this paper, we calculate the effective conductivity using the 3D finite element method for a large number of two-phase medium stochastic models. The GMR is then employed as an effective conductivity model to fit the data. It shows a very close relationship between the parameter J of GMR and the ratio of conductivities of the two phases. We obtain the equations of the parameter J with the ratio of conductivity of two phases for the first time. On this basis, we can quickly predict (or calculate) the effective conductivity of any twophase medium stochastic model. The result is much more accurate than two other available effective conductivity models for the stochastic medium, which are the random model and effective medium theory model, laying a solid base for detailed evaluation of oil reservoirs. 展开更多
关键词 generalized mixture rule two-phase media effective conductivity
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Generalized Numerical Radius of Real Quaternion Matrices with Symmetric Function
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作者 夏铁成 张鸿庆 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期34-38,共5页
In the paper the generalized numerical radiuses of real quaternion matrices with symmetric function are defined and theirs inequalities are given.
关键词 numerical radius generalized numerical radius symmetric function
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The Fourier Transform of a Sort of Generalized Function
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作者 祝同江 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期106+101-106,共7页
The Fourier transforms of functions X ln e are given. where λ is a complex constant (λ≠-1,-2. …), a is a complex number. m=0. 1. 2,…,and
关键词 Fourier transform generalized function analytic exextension
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Effect of PTCA and stenting on left ventricular diastolic function in patients with CHD
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作者 傅向华 《介入放射学杂志》 CSCD 2003年第S1期151-,共1页
Objective The aim of this study was to determine the effect of successful coronary revascularisation on left ventricular diastolic function.Methods We consecutively studied the diastolic function by Doppler echocardio... Objective The aim of this study was to determine the effect of successful coronary revascularisation on left ventricular diastolic function.Methods We consecutively studied the diastolic function by Doppler echocardiography in 125 patients with one vessel disease before and 48 hours after selective coronary angioplasty. The following parameters of left ventricular diastolic function were evaluated: peak early (VE, m/s) and peak late diastolic (VA, m/s) flow velocity, E/A ratio, acceleration time (AT, ms), deceleration time (DT, ms) and isovolumetric relaxation time (IVRT, ms). Ejection fraction (EF; %) was determined and used to characterise systolic left ventricular function. Results All of the patients were initially successful treated with coronary angioplasty (residual stenosis <40% ). In 98 patients( 78.4% ) stents were used to improve an inadequate result after coronary angioplasty. Both patient groups (27 patients with coronary angioplasty and 98 patients with combined coronary angioplasty and stent implantation) showed no relevant differences concerning sex, age, atherosclerotic risk factors, exercise capacity and results of exercise electrocardiography. All patients who underwent stent implantation showed an early improvement of left ventricular diastolic function 48 hours after revascularisation. Surprisingly there was no significant short term improvement (48 hours) of diastolic function in patients with initially successful angioplasty.Conclusions We suppose that stent implantation might normalize coronary blood flow faster than that of coronary balloon angioplasty. 展开更多
关键词 effect of PTCA and stenting on left ventricular diastolic function in patients with CHD PTCA LEFT in on of with
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Site effects by generalized inversion technique using strong motion recordings of the 2008 Wenchuan earthquake 被引量:25
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作者 Ren Yefei Wen Ruizhi +1 位作者 Hiroaki Yamanaka Toshihide Kashima 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期165-184,共20页
The generalized inversion of S-wave amplitude spectra from the free-field strong motion recordings of the China National Strong Motion Observation Network System (NSMONS) are used to evaluate the site effects in the... The generalized inversion of S-wave amplitude spectra from the free-field strong motion recordings of the China National Strong Motion Observation Network System (NSMONS) are used to evaluate the site effects in the Wenchuan area. In this regard, a total of 602 recordings from 96 aftershocks of the Wenchuan earthquake with magnitudes of M3.7-M6.5 were selected as a dataset. These recordings were obtained from 28 stations at a hypocenter distance ranging from 30 km to 150 km. The inversion results have been verified as reliable by comparing the site response at station 62WUD using the Generalized Inversion Technique (GIT) and the Standard Spectral Ratio method (SSR). For all 28 stations, the site predominant frequency F and the average site amplification in different frequency bands of 1.0-5.0 Hz, 5.0-10.0 Hz and 1.0-10.0 Hz have been calculated based on the inversion results. Compared with the results from the horizontal-to-vertical spectral ratio (HVSR) method, it shows that the HVSR method can reasonably estimate the site predominant frequency but underestimates the site amplification. The linear fitting between the average site amplification for each frequency band and the V20 (the average uppermost-20 m shear wave velocity) shows good correlation. A distance measurement called the asperity distance DAspt is proposed to reasonably characterize the source-to-site distance for large earthquakes. Finally, the inversed site response is used to identify the soil nonlinearity in the main shock and aftershocks of Wenchuan earthquake. In ten of the 28 stations analyzed in the main shock, the soil behaved nonlinearly, where the ground motion level is apparently beyond a threshold ofPGA 〉 300 cm/s^2 or PGV 〉 20 cm/s, and only one station coded 51SFB has evidence of soil nonlinear behavior in the aftershocks. 展开更多
关键词 generalized inversion technique site effect Wenchuan earthquake soil nonlinearity predominant frequency site amplification
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Some new exact solutions of Jacobian elliptic function about the generalized Boussinesq equation and Boussinesq-Burgers equation 被引量:9
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作者 张亮 张立凤 李崇银 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期403-410,共8页
By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic functio... By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions. 展开更多
关键词 generalized Boussinesq equation Boussinesq-Burgers equation Jacobian elliptic function modified mapping method
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Ecological effects of crude oil residues on the functional diversity of soil microorganisms in three weed rhizospheres 被引量:6
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作者 ZHANG Qian-ru ZHOU Qi-xing +2 位作者 REN Li-ping ZHU Yong-guan SUN Shu-lan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1101-1106,共6页
Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion (Taraxacum officinale),... Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion (Taraxacum officinale), jerusalem artichoke (Silphiurn perfoliatum L.) and evening primrose (A colypha australis L.) rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units (CFUs) in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke (S. perfoliatum) rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant (p〉0.05) difference in the Shannon's diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues. 展开更多
关键词 ecological effect weed rhizosphere crude oil residue soil microorganism functional diversity
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Weapon effectiveness and the shapes of damage functions 被引量:8
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作者 Sei-Hoon Moon 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期617-632,共16页
This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with ... This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite significant differences from using the original Carleton damage function with a correct shape factor when weapon’s delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced. 展开更多
关键词 Weapon effectiveness Point target Area target Cookie-cutter damage function Carleton damage function
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The generalized Chapman-Richards function and applications to tree and stand growth 被引量:10
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作者 刘兆刚 李凤日 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期19-26,共8页
The generalized Chapman-Richards model was derived from the Chapman-Richards function in which parameters h, k and m were unconstrained. Based on the structure of solutions and biological interpretations, the model co... The generalized Chapman-Richards model was derived from the Chapman-Richards function in which parameters h, k and m were unconstrained. Based on the structure of solutions and biological interpretations, the model could be classified into eight cases (three categories) at all and among them only 4 kinds of cases are suitable in forestry that represent four typical growth patterns of trees and stands. For each of 4 equations, the model properties and biological interpretations for parameters were discussed in detail. The generalized Chapman-Richards model was capable of describing a wide range of growth curves that was asymptotic or nonasymptotic, with or without inflection point. In order to illustrate the versatility of the model, it was fitted to a group of data sets concerning the DBH growth of cryptomeria plantations with 4 initial densities and the DBH and height growth of natural Korean pine tree. Comparing the generalized Chapman-Richards function and the Schnute model, it was found that the parameters and expressions of the two models were interchangeable in theory, and the fitting results were explicitly identical in empirical applications. 展开更多
关键词 generalized Chapman-Richards function Schnute model Growth model Growth pattern Cryptomeria japonica Pinus koraiensis
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Improved theory of generalized meteo-ballistic weighting factor functions and their use 被引量:1
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作者 Vladimir CECH Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期242-254,共13页
It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire ... It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget model.Trajectories calculated under non-standard conditions are considered to be perturbed.The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity functions.WFFs are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as well.We have found that the existing theory of WFF calculation has several significant shortcomings.The aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies found.Using this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms. 展开更多
关键词 EXTERIOR BALLISTIC Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity function (generalized) weighting (factor) function(curve) (generalized) effect function Norm effect
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Chemical constituents,biological functions and pharmacological effects for comprehensive utilization of Eucommia ulmoides Oliver 被引量:29
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作者 Yi-Fan Xing Dong He +6 位作者 Yi Wang Wen Zeng Chong Zhang Yuan Lu Nan Su Yan-Hua Kong Xin-Hui Xing 《Food Science and Human Wellness》 SCIE 2019年第2期177-188,共12页
Eucommia ulmoides Oliver is a native plant and valuable tonic Chinese medicine in China with a long history,great economic value and comprehensive development potential.Traditionally,the comprehensive utilization rate... Eucommia ulmoides Oliver is a native plant and valuable tonic Chinese medicine in China with a long history,great economic value and comprehensive development potential.Traditionally,the comprehensive utilization rate of E.ulmoides Oliv.is still very low,only bark has been used as medicine and other parts of Eucommia ulmoides Oliv.cannot be fully utilized,even the leaves have been well utilized in food products in Japan in the past decades.In order to improve the comprehensive utilization efficiency of E.ulmoides Oliv.,in this review,we summarized the varieties and contents of main active compounds,biological functions and pharmacological effects in different parts of E.ulmoides Oliv.The findings suggest that other parts of E.ulmoides Oliv.could replace the bark of E.ulmoides Oliv.to some extent besides of their respective applications.The unique and extensive physiological functions between different parts of E.ulmoides Oliv.indicate that the comprehensive utilization of E.ulmoides Oliv.has a wide space to develop,which is also an effective way to protect E.ulmoides Oliv.resources and improve its the utilization rate. 展开更多
关键词 Eucommia ulmoides Oliver Comprehensive utilization Chemical constituents Biological functions Pharmacological effects
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MONOTONICITY AND INEQUALITIES FOR THE GENERALIZED DISTORTION FUNCTION 被引量:2
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作者 马晓艳 褚玉明 王飞 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1759-1766,共8页
The authors prove some monotonicity properties of functions involving the generalized Agard distortion function ηg(a,t), and obtain some inequalities for ηk(a, t) and relative distortion functions.
关键词 generalized modular equation generalized η-distortion function monotonic-ity inequality
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Effects of Catalysis and Separator Functionalization on High-Energy Lithium–Sulfur Batteries:A Complete Review 被引量:7
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作者 Muhammad Kashif Aslam Sidra Jamil +1 位作者 Shahid Hussain Maowen Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期333-355,共23页
Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising nex... Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising next-generation rechargeable energy storage devices.However,the“shuttle effect”of polysulfide results in the passivation of metal lithium anode,the decrease of battery capacity and coulombic efficiency,and the deterioration of cycle stability.To realize the commercialization of Li-S batteries,its serious“shuttle effect”needs to be suppress.The commercial separators are ineffective to suppress this effect because of its large pore size.Therefore,it is an effective strategy to modify the separator surface and introduce functional modified layer.In addition to the blocking strategy,the catalysis of polysulfide conversion reaction is also an important factor hindering the migration of polysulfides.In this review,the principles of separator modification,functionalization,and catalysis in Li-S batteries are reviewed.Furthermore,the research trend of separator functionalization and polysulfide catalysis in the future is prospected. 展开更多
关键词 CATALYSIS Li-S batteries POLYSULFIDES separator functionalization shuttle effect
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Functional diversity dominates positive species mixture effects on ecosystem multifunctionality in subtropical plantations 被引量:5
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作者 Xi Li Hui Wang +4 位作者 Junwei Luan Scott X.Chang Bing Gao Yi Wang Shirong Liu 《Forest Ecosystems》 SCIE CSCD 2022年第3期417-426,共10页
Mixed-species plantations generally exhibit higher ecosystem multifunctionality than monospecific plantations.However,it is unclear how tree species functional composition influences species mixture effects on ecosyst... Mixed-species plantations generally exhibit higher ecosystem multifunctionality than monospecific plantations.However,it is unclear how tree species functional composition influences species mixture effects on ecosystem multifunctionality.We selected 171 monospecific and mixed-species plantations from nine regions across subtropical China,and quantified 13 key ecosystem functional properties to investigate how species mixture effects on ecosystem multifunctionality are modulated by functional diversity and identity.We found that ecosystem multifunctionality was significantly higher(p<0.05)in mixed tree plantations than in monospecific plantations except the mixed-conifer species plantations.Across all regions,ecosystem multifunctionality was significantly higher(p<0.05)in mixed conifer-broadleaf plantations than in monospecific plantations of the corresponding species,but not different between mixed and monospecific coniferous plantations.The magnitude of species mixture effects on ecosystem multifunctionality varied greatly with tree species compositions.Taking Cunninghamia lanceolata Lamb.as an example,the effects varied from a range of 2.0%–9.6%when mixed with a conifer species to 36%–87%when mixed with a broadleaf species.The functional diversity was the dominate driver shaping ecosystem multifunctionality,while functional identity,as expressed by community-weighted mean of specific leaf area,also had a positive effect on ecosystem multifunctionality through the increased below-ground nitrogen and phosphorus stocks regulated by specific leaf area of the mixing tree species.Our study highlights the important role of functional diversity in shaping ecosystem multifunctionality across region-wide environmental conditions.Mixed conifer-broadleaf tree plantations with distinct functional traits benefit the enhancement of ecosystem multifunctionality,and the magnitude of species mixture effects is modulated by the functional identity of tree species composition;those relationships deserve a special consideration in multifunctional management context of subtropical plantations. 展开更多
关键词 Ecosystem multifunctionality Species mixture effects functional diversity functional identity Mixed tree plantations Monospecific plantations
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THE HILBERT BOUNDARY VALUE PROBLEM FOR GENERALIZED ANALYTIC FUNCTIONS IN CLIFFORD ANALYSIS 被引量:2
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作者 司中伟 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期393-403,共11页
Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f sati... Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f satisfies the equation Lf=0,where ……qi 〉0, i =-, 1, - ……, n. In this article, we first give the kernel function for the generalized analytic function. Further, the Hilbert boundary value problem for generalized analytic functions in Rn+1 will be investigated. 展开更多
关键词 generalized analytic function Hilbert boundary value problem H^u function
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