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Investigation of the Interaction Mechanism between Lignin Structural Units and Enzyme 被引量:2
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作者 Lijing Huang Penghui Li +1 位作者 Kangjie Jiang Wenjuan Wu 《Journal of Renewable Materials》 SCIE EI 2023年第4期1613-1626,共14页
The effect of lignin structural units on enzymatic hydrolysis of lignocellulosic biomass was investigated,especially the inhibitory role of lignin in non-productive adsorption with enzymes.Milled wood lignin(MWL)was i... The effect of lignin structural units on enzymatic hydrolysis of lignocellulosic biomass was investigated,especially the inhibitory role of lignin in non-productive adsorption with enzymes.Milled wood lignin(MWL)was isolated from different hardwoods of poplar,eucalyptus and acacia.The isolated lignin samples were characterized by elemental analysis,gel permeation chromatography,nitrobenzene oxidation and fourier infrared spectroscopy.The mechanism of lignin structural units on enzymatic hydrolysis of cellulose was studied by quartz crystal microbalance(QCM).The results showed that different structural units of lignin had different adsorption capacity for enzymes.The results of nitrobenzene oxidation indicated that the S/G ratio(S:syringyl-like lignin structures;G:guaiacyl-like lignin structures)of lignin of poplar was 0.99,that of eucalyptus was 1.92 and that of acacia was 1.34.According to the results of QCM,the adsorption capacity of the three lignin films was as follows:Poplar MWL(S/G ratio 0.99)<Acacia MWL(S/G ratio 1.34)<Eucalyptus MWL(S/G ratio 1.92).Eucalyptus MWL with higher degree of condensation and S/G ratio showed stronger affinity to enzymes and more non-productive adsorption with enzymes,resulting in less adsorption between enzymes and cellulose,and lower enzymatic hydrolysis efficiency. 展开更多
关键词 LIGNIN structural unit enzyme adsorption enzymatic hydrolysis
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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N) 被引量:1
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作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNESS unit ball
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Systematic Review of Community Type 2 Diabetes Structured Health Education (CT2DSHE)
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作者 Gift Phiri 《Open Journal of Nursing》 2024年第8期377-400,共24页
Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming t... Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming to summarize the results of prior primary research studies on available evidence Community type 2 diabetes structured education (CT2DSHE). Methods: Research question: Type 2 diabetic structured health education within a community how effective is it? Qualitative Systematic review, defined as a way to get reliable and objective picture of current available evidence on the specific topic—(CT2DSHE), (Denscombe, 2021) through reflexivity synthesis of available data as an example. This is valuable in time constraints such as project assignments that must be met within specific time and also to bring together available evidence together [1]. Results: This review has shown that CT2DSHE is effective with seven out of the eleven authors supporting, three authors against and one was neutral, further showed that knowledge and skills acquired can last longer with patient activation improved among T2DM patients ideal for sustaining their self-management of T2DM. Conclusion: This research provides suggestive answers to the research question: “Type 2 diabetic structured health education within a community how effective is it?”, This has demonstrated CT2DSHE effectiveness in knowledge acquisition and improving T2DM awareness among T2DM patients, whilst evidencing long effects beyond the study times of 3 - 9 months period in relation to patient activation. Also Identified diabetes education self-management on newly diagnosed (DESMOND) patient as CT2DSHE program for recommendation. Patient or Public Contribution: This work aspires to contribute to CT2DSHE in these areas;Influencing policy decision-making for community diabetes care within the UK and world at large., Contributing to already vast knowledge on diabetes self-management and reasons why?, Influencing educators on how CT2DSHEP are designed, delivered by putting the patient at the Centre and bringing different perspectives on CT2DSHEP in one place that is serving users time of having to consult several resources especially busy clinicians [2] [3]. 展开更多
关键词 Community Health EDUCATION EFFECTIVENESS Impact Structured and Planned Type 2 Diabetes (T2DM)
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO_4-H_2O and NaF-H_2O binary solutions and NaClO_4-NaF-H_2O ternary solution 被引量:1
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作者 Xue-min Yang Wei-jie Zhao +2 位作者 Han-jie Guo Qiang Zhang Jian Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第5期546-557,共12页
A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions and NaClO4-NaF-H2O ternary strong electrolyte aqueous solutions was develo... A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions and NaClO4-NaF-H2O ternary strong electrolyte aqueous solutions was developed based on the ion and molecule coexistence theory (IMCT). A transformation coefficient was needed to compare the calculated mass action concentration and the reported activity, because they were usually obtained at different standard states and concentration units. The results show that transformation coefficients between the calculated mass action concentrations and the reported activities of the same components change in a very narrow range. The transformed mass action concentrations of structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions agree well with the reported activities. The transformed mass action concentrations of structural units or ion couples in NaClO4-NaF-H2O ternary solution are also in good agreement with the reported activities in a total ionic strength range from 0.1 to 0.9 mol/kg H2O by the 0.1 mol/kg step with different ionic strength fractions of 0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1, respectively. The results indicate that the developed thermodynamic model can reveal the structural characteristics of binary and ternary strong electrolyte aqueous solutions, and the calculated mass action concentrations of structural units or ion couples also strictly follow the mass action law. 展开更多
关键词 binary systems ternary systems thermodynamic model activity coefficient structural unit
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Effect of Structural Units on the Adhesion of Acrylic Copolymers to Fibers for Warp Sizing 被引量:1
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作者 祝志峰 许德生 徐珍珍 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期825-829,共5页
Radical copolymerization of acrylic acid(AA)with acrylamide(AM)or acrylamide/acrylonitrile(AM/AN)was initiated with ammonium persulfate as initiator to produce acrylic copolymers such as bicopolymer poly(AM-co-AA)and ... Radical copolymerization of acrylic acid(AA)with acrylamide(AM)or acrylamide/acrylonitrile(AM/AN)was initiated with ammonium persulfate as initiator to produce acrylic copolymers such as bicopolymer poly(AM-co-AA)and tercopolymer poly(AM-co-AN-co-AA)for revealing the effects of the structural units of the copolymers on the adhesion of the copolymers to polyester or cotton fibers for warp sizing.The adhesion was evaluated in terms of tensile strength and work-to-break of a roving impregnated with the copolymer solution.It was found that the adhesion strongly depended on type and amount of the units incorporated into the copolymeric chains.Whether the fiber is cotton or polyester,the adhesion of the bicopolymer poly(AM-co-AA)is greater than that of polyacrylic acid or polyacyamide.Excessively increasing the amount of AM or AA unit in poly(AM-co-AA)lowers the adhesion.To enhance the adhesion of the bicopolymer,a favorable mole ratio of AM to AA is 70/30.Based on this mole ratio,incorporation of acrylonitrile units into poly(AM-co-AA)to form tercopolymer enhances the adhesion. 展开更多
关键词 acrylic copolymers warp sizes structural units ADHESION
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Coordination properties and structural units distribution of Q_T^i in calcium aluminosilicate melts from MD simulation 被引量:1
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作者 吴永全 蒋国昌 +2 位作者 尤静林 侯怀宇 陈辉 《Journal of Central South University of Technology》 2004年第1期6-14,共9页
The distribution of Al (j) and the structural units distribution of Qi T in calcium aluminosilicate melts were studied by means of molecular dynamics simulation. The results show that provided there exists lower-fie... The distribution of Al (j) and the structural units distribution of Qi T in calcium aluminosilicate melts were studied by means of molecular dynamics simulation. The results show that provided there exists lower-field strength cation relative to Al3+, such as alkaline and alkaline earth metals, Al will be four-coordinated but not six-coordinated. Meanwhile, if there exist a large number of higher-field strength cations such as Si4+ and little lower-field strength cation, six-coordinated aluminum will be formed. The relation of structural units distribution of Qi T with chemical composition shift was also extracted, showing that as Ca2+ exists, the distributions of Qi Si, Qi Al or Qi T have the similar changing trend with the variation of component. Because of high-temperature effect, the Al-tetrahedral units in melts are greatly active and unstable and there exist dynamic transforming equilibria of Al(3)Al(4) and (Al(5))Al(4). The three-coordinated oxygen and charge-compensated bridging oxygen are proposed to explain phenomena of the negative charge redundancy of AlO4 and location of network modifier with charge-compensated function in aluminosilicate melts. 展开更多
关键词 Molecular dynamics simulation calcium aluminosilicate melt coordination number structural unit of tetrahedra
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Calculating models of mass action concentrations for structural units or ion couples in RbCl-H_2O binary system and RbCl-RbNO_3-H_2O ternary system 被引量:1
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作者 郭汉杰 杨学民 赵伟洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1112-1120,共9页
Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and... Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and molecule coexistence theory at 298.15 K.A transformation coefficient is needed to compare the calculated mass action concentration and the reported activity because they are obtained at different standard states and concentration units.The results show that the transformation coefficients between the calculated mass action concentrations and the reported activities of the same structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions change in a very narrow range.The transformed mass action concentrations of structural units or ion couples in RbCl-H2O binary system are in good agreement with the reported activities. The transformed mass action concentrations of RbCl and RbNO3 in RbCl-RbNO3-H2O ternary solution are also in good agreement with the reported activities,aRbCl and 3RbNOa,with different total ionic strengths as 0.01,0.05,0.1,0.5,1.0,1.5,2.0,3.0 and 3.5 mol/kg,respectively.All those results mean the developed thermodynamic model of strong electrolyte aqueous solutions can reflect structural characteristics of RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions and the mass action concentration also strictly follows the mass action law. 展开更多
关键词 mass action concentration ACTIVITY ion and molecule coexistence theory RbCl-H2O RbCl-RbNO3-H2O structural unit ion couple
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Specific primers design based on the superoxide dismutase b gene for Trypanosoma cruzi as a screening tool:Validation method using strains from Colombia classified according to their discrete typing unit
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作者 Francisco Olmo Javier Escobedo-Ortegón +4 位作者 Patricia Palma Manuel Sánchez-Moreno Ana Mejía-Jaramillo Omar Triana Clotilde Marín 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第11期854-859,共6页
Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biologica... Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biological samples.Methods:Strains were isolated,DNA extracted,and classified by using three Polymerase Chain Reactions(PCR).Subsequently this DNA was used along with other isolates of various biological samples,for a new PCR using primers designed.Finally,the amplified fragments were sequenced.Results:It was observed the predominance of DTU i in Colombia,as well as the specificity of our primers for detection of T.cruzi,while no band was obtained when other species were used.Conclusions:This work reveals the genetic variability of 21 new isolates of T.cruzi in Colombia.Our primers confirmed their specificity for detecting the presence of T.cruzi. 展开更多
关键词 TRYPANOSOMA CRUZI Polymerase chain reaction Colombia Superoxide dismutase GENE b-based primers DISCRETE typing unit
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Structural stability estimation of whirling unit 被引量:2
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作者 Son-Jae HWAN Han-Chang WOO +1 位作者 Lee-Sang RYONG Lee-Young MOON 《中国有色金属学会会刊:英文版》 CSCD 2009年第B09期202-208,共7页
Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by usin... Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by using ADAMS and NASTRAN softwares. Each maximum force acting on the bearing attached to the spindle assembly and the cutting tool attached to the whirling ring with the rotating speed of 6 000 r/min was 235 N and 902 N respectively. The maximum stress of 0.74 MPa on the base frame is far smaller than the yield strength of 282 MPa. The calculated natural frequency of 148 Hz of the system is far from the frequency of the driving speed of 6 000 r/min. The experimentally obtained maximum cutting force of 792 N is smaller than that of calculated value. And the experimentally obtained natural frequency of 118 Hz is beyond the driving speed of 6000 r/min. From above results it can be judged that the whirling system is statically and dynamically stable. 展开更多
关键词 旋转工件 稳定性评价 NASTRAN软件 动态稳定性 结构 单元 固有频率 行车速度
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Optimum Structural Design of a Chain-Driving Pumping Unit
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作者 Zhang Ailin and Liu Yang(Doctors,Qinhuangdao Branch of Daqing Petroleum Institute) 《China Oil & Gas》 CAS 1994年第4期45-47,共3页
In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain mov... In this paper the pumping unit of type QLCJ14-6 is studied.Through the belt driving unit,the mo-tor drives the driving sprocket in which the rotation rate has been reduced by the reduction ge arbox.The locus chain moves between the driving sprocket and upper sprocket which are vertically set.There's a special chain element in the locus chain,which drives the reciprocating holster with the main shaft linchpin and slide block.The r reciprocating g holster could only move up and down when the locus chain moves in a circle.In this way the up and down stroke of the sucker rod and the mac hine is realized.The lower end of the reciprocating holster is con-nected with the equilibrium system to make the structure balance.The balancing cylinder is re-placed by the balancing block to make the structure simplified. 展开更多
关键词 CHAIN DRIVE PUMPING unit structural design Optimization
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Structural features and exploration targets of platform margins in Sinian Dengying Formation in Deyang-Anyue Rift, Sichuan Basin, SW China 被引量:1
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作者 ZENG Fuying YANG Wei +12 位作者 WEI Guoqi YI Haiyong ZENG Yunxian ZHOU Gang YI Shiwei WANG Wenzhi ZHANG San JIANG Qingchun HUANG Shipeng HU Mingyi HAO Cuiguo WANG Yuan ZHANG Xuan 《Petroleum Exploration and Development》 SCIE 2023年第2期306-320,共15页
Based on the seismic, logging, drilling and other data, the distribution, structural types and mound-shoal hydrocarbon accumulation characteristics of platform margins of the Sinian Dengying Formation in the Deyang-An... Based on the seismic, logging, drilling and other data, the distribution, structural types and mound-shoal hydrocarbon accumulation characteristics of platform margins of the Sinian Dengying Formation in the Deyang-Anyue Rift and its periphery were analyzed. Four types of platform margins are developed in the Dengying Formation, i.e., single-stage fault-controlled platform margin, multi-stage fault-controlled platform margin, gentle slope platform margin, and overlapping platform margin. In the Gaoshiti West-Weiyuan East area, single-stage fault controlled platform margins are developed in the Deng 2 Member, which trend in nearly NEE direction and are shielded by faults and mudstones, forming fault-controlled–lithologic traps. In the Lezhi-Penglai area, independent and multi-stage fault controlled platform margins are developed in the Deng 2 Member, which trend in NE direction and are controlled by synsedimentary faults;the mound-shoal complexes are aggraded and built on the hanging walls of the faults, and they are shielded by tight intertidal belts and the Lower Cambrian source rocks in multiple directions, forming fault-controlled–lithologic and other composite traps. In the Weiyuan-Ziyang area, gentle slope platform margins are developed in the Deng 2 Member, which trend in NW direction;the mound-shoal complexes are mostly thin interbeds as continuous bands and shielded by tight intertidal belts in the updip direction, forming lithologic traps. In the Gaoshiti-Moxi-Yanting area, overlapping platform margins are developed in the Deng 2 and Deng 4 members;the mound-shoal complexes are aggraded and overlaid to create platform margin buildup with a huge thickness and sealed by tight intertidal belts and the Lower Cambrian mudstones in the updip direction, forming large-scale lithologic traps on the north slope of the Central Sichuan Paleouplift. To summarize, the mound-shoal complexes on the platform margins in the Dengying Formation in the Penglai-Zhongjiang area, Moxi North-Yanting area and Weiyuan-Ziyang area are large in scale, with estimated resources of 1.58×1012 m3, and they will be the key targets for the future exploration of the Dengying Formation in the Sichuan Basin. 展开更多
关键词 Sichuan Basin Deyang-Anyue Rift structural type of platform margin mound-shoal complex on the platform margin lithologic trap Sinian Dengying Formation exploration direction
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Is There Hysteresis in Unemployment in OECD Countries? Evidence From Panel Unit Root Test With Structural Breaks
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作者 Meliha Ener Feyza Ariea 《Chinese Business Review》 2011年第4期294-304,共11页
This study tests the hysteresis hypothesis of unemployment in fifteen OECD countries by using panel unit root tests which allow for structural breaks. We apply annual unemployment rates covering 1985-2008 periods. We ... This study tests the hysteresis hypothesis of unemployment in fifteen OECD countries by using panel unit root tests which allow for structural breaks. We apply annual unemployment rates covering 1985-2008 periods. We test whether unemployment rates are stationary by using second generation tests which allow cross section dependency among series and panel unit root test based on structural break advanced by Carrion-i-Silvestre, Barrio-Castro and Lopez-Bazo (2005). We find series as a stationary process with structural breaks according to Carrion-i Silvestre et al. (2005) test, while we find series as unit root process with second generation panel unit root test. According to the Carrion-i Silvestre et al. (2005) test, we find the evidence of absence of hysteresis in analyzed countries. As a result, temporary shocks have temporary effects on unemployment instead of permanent effect. Structural factors can affect the natural rate of unemployment and, therefore, unemployment would be stationary around a process that is subject to structural breaks. So, there still exists a unique natural rate of unemployment to which the economy eventually will converge. 展开更多
关键词 structural break UNEMPLOYMENT cross-section dependence panel unit root tests
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Numerical Analysis of the Influence of Geometry of Ceramic Units (Blocks) on Structural Walls
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作者 Gihad Mohamad Eduardo Rizzatti +2 位作者 Humberto Roman Gerson M. S. Alva Andre Lubeck 《Journal of Civil Engineering and Architecture》 2016年第1期44-52,共9页
This paper presents finite element results of ceramic masonry prisms and walls under concentric compression. Four different hole geometries of ceramic units were studied (called Types A, B, C and D). The A-type unit... This paper presents finite element results of ceramic masonry prisms and walls under concentric compression. Four different hole geometries of ceramic units were studied (called Types A, B, C and D). The A-type unit had two rectangular hollows, B-type and C-type units have two rounded hollows and different net areas, mad the D-type unit had two rectangular hollows and a double central web. This study analyzed units, prisms and structural walls joined by bedding mortar. The objective was to verify the stress distribution in units and mortars. The results showed that the distribution of compressive stress along the length and width of those units was uniform, but lateral tensile stress along the length was distinct for different geometries. In addition, this study observed that hollow shapes have an important influence in stress distribution. The D-type unit was the one that showed more uniform tension distribution, without peaks of stress concentration. This indicates that a D-type unit is the most efficient unit for use in masonry structures. 展开更多
关键词 Ceramic units structural masonry geometry.
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Independent and Combined Effect of Some Soil Tillage Systems on Nitrogen and Carbon Concentration in Soil Structural Units of Haplic Chernozems
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作者 Margarita Nankova Peter Yankov 《Journal of Agricultural Science and Technology(B)》 2015年第7期465-476,共12页
This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of... This paper aimed at studying the effect of different types of soil tillage systems on the change of total carbon (C) and nitrogen (N) in the soil structural units of different size after dry structural analysis of soil. The research was carried out in a 6-field rotation system (grain maize-wheat-sunflower-wheat-bean-wheat) at the end of the 2nd rotation. Six out of 24 soil tillage systems were selected; they were applied independently and in combination in the crop rotation. After that, they were compared to the system with constant deep plowing. So a total of seven soil tillage systems were investigated. The selected systems for main soil tillage were the following: plowing (control variant), disking, cutting, nil tillage (direct sowing), plowing-disking, plowing-nil tillage, disking-nil tillage. Three depths of 0-10, 10-20 and 20-30 cm were studied, as well as soil structural units were of the following sizes: 〉 10 mm, 10-5, 5-3, 3-1, 1-0.25 mm and 〈 0.25 mm. As a result of systematic implementation of different soil tillage systems, higher N and C concentrations were established by the layers according to constant plowing. Constant disking and its alternation with nil tillage increased the total N concentration with 15.6% and 11.1%, respectively, in comparison with the constant plowing. The same was valid for C concentration in soil, but the highest increase was established in the variants with constant cutting and nil tillage. The exceeding was with 14.0% and 13.2%, in comparison to constant plowing. The redistribution of N and C depending on the structural soil units was most expressed in the 0-10 cm and 10-20 cm layers. The highest amounts of C and N were found in the soil units with size less than 5 mm, mainly in the 〈 0.25 mm fraction. At depth of 20-30 cm, the role of the size of soil structural units for C and N redistribution decreased strongly. The values of C/N ratio were moderate only under the use of constant disking. This index was low under all other soil tillage systems. The correlation of total N with C in soil was high, positive and significant depending on the size of structural soil units and the tillage systems, as average for the investigated factors in this experiment. The minimal tillage and the tillage without turning of soil, used independently and in combination, had the highest contribution to preserving the organic matter in the haplic Chernozems of Dobrudzha region. 展开更多
关键词 Soil tillage systems soil C total soil N soil structural units.
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Optical transmission through basic-structural-unit superlattices
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作者 张国刚 杨湘波 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期627-633,共7页
In this paper, by the transparent-component-decimation (TCD) method we obtain three kinds of new basic- components (BCs) through simplifying and decomposing the BCs of three-component Thue-Morse (3CTM) sequence.... In this paper, by the transparent-component-decimation (TCD) method we obtain three kinds of new basic- components (BCs) through simplifying and decomposing the BCs of three-component Thue-Morse (3CTM) sequence. Based on these new BCs we propose a type of basic-structural-units (BSUs) and investigate the optical transmission of the one-dimensional (1D) superlattices composed of these BSUs. It is found that if the substrates of the 1D BSU superlattices are certain, the optical transmission at the central wavelength (CW) will be determined completely by the number and the type of BSUs and has nothing to do with the marshalling sequence. In particular, if the substrates are identical, the numbers of different types of BSUs are all the same and the middle two elements of BSUs constitute a cycle, then no matter whether the system is periodic, or quasiperiodic, or aperiodic, or unordered, or even random, it will be transparent at the CW. The conclusion is confirmed by the numerical results. Similar to the even layers of neighbourhood identical elements in TCD method, such a kind of optical BSU subsystem can also be decimated from the chain in the process of transmission investigation. There would be a potential application in the designing of some interesting optical devices. 展开更多
关键词 optical transmission basic-structural-units SUPERLATTICES
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ON THE FIGIEL TYPE PROBLEM AND EXTENSION OFε-ISOMETRY BETWEEN UNIT SPHERES
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作者 刘锐 尹际富 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1503-1517,共15页
This paper studies two isometric problems between unit spheres of Banach spaces.In the first part,we introduce and study the Figiel type problem of isometric embeddings between unit spheres.However,the classical Figie... This paper studies two isometric problems between unit spheres of Banach spaces.In the first part,we introduce and study the Figiel type problem of isometric embeddings between unit spheres.However,the classical Figiel theorem on the whole space cannot be trivially generalized to this case,and this is pointed out by a counterexample.After establishing this,we find a natural necessary condition required by the existence of the Figiel operator.Furthermore,we prove that when X is a space with the T-property,this condition is also sufficient for an isometric embedding T:S_(X)→S_(Y) to admit the Figiel operator.This answers the Figiel type problem on unit spheres for a large class of spaces.In the second part,we consider the extension of bijectiveε-isometries between unit spheres of two Banach spaces.It is shown that every bijectiveε-isometry between unit spheres of a local GL-space and another Banach space can be extended to be a bijective 5ε-isometry between the corresponding unit balls.In particular,whenε=0,this recovers the MUP for local GL-spaces obtained in[40]. 展开更多
关键词 unit spheres isometric embedding Figiel type problem ε-isometry EXTENSION
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Clinical and biochemical predictors of intensive care unit admission among patients with diabetic ketoacidosis
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作者 Adeel Ahmad Khan Fateen Ata +2 位作者 Phool Iqbal Mohammed Bashir Anand Kartha 《World Journal of Diabetes》 SCIE 2023年第3期271-278,共8页
BACKGROUND Diabetic ketoacidosis(DKA)contributes to 94%of diabetes-related hospital admissions,and its incidence is rising.Due to the complexity of its management and the need for rigorous monitoring,many DKA patients... BACKGROUND Diabetic ketoacidosis(DKA)contributes to 94%of diabetes-related hospital admissions,and its incidence is rising.Due to the complexity of its management and the need for rigorous monitoring,many DKA patients are managed in the intensive care unit(ICU).However,studies comparing DKA patients managed in ICU to non-ICU settings show an increase in healthcare costs without significantly affecting patient outcomes.It is,therefore,essential to identify suitable candidates for ICU care in DKA patients.AIM To evaluate factors that predict the requirement for ICU care in DKA patients.METHODS This retrospective study included consecutive patients with index DKA episodes who presented to the emergency department of four general hospitals of Hamad Medical Corporation,Doha,Qatar,between January 2015 and March 2021.All adult patients(>14 years)fulfilling the American Diabetes Association criteria for DKA diagnosis were included.RESULTS We included 922 patients with DKA in the final analysis,of which 229(25%)were managed in the ICU.Compared to non-ICU patients,patients admitted to ICU were older[mean(SD)age of 40.4±13.7 years vs 34.5±14.6 years;P<0.001],had a higher body mass index[median(IQR)of 24.6(21.5-28.4)kg/m2 vs 23.7(20.3-27.9)kg/m2;P<0.030],had T2DM(61.6%)and were predominantly males(69%vs 31%;P<0.020).ICU patients had a higher white blood cell count[median(IQR)of 15.1(10.2-21.2)×103/uL vs 11.2(7.9-15.7)×103/uL,P<0.001],urea[median(IQR)of 6.5(4.6-10.3)mmol/L vs 5.6(4.0-8.0)mmol/L;P<0.001],creatinine[median(IQR)of 99(75-144)mmol/L vs 82(63-144)mmol/L;P<0.001],C-reactive protein[median(IQR)of 27(9-83)mg/L vs 14(5-33)mg/L;P<0.001]and anion gap[median(IQR)of 24.0(19.2-29.0)mEq/L vs 22(17-27)mEq/L;P<0.001];while a lower venous pH[mean(SD)of 7.10±0.15 vs 7.20±0.13;P<0.001]and bicarbonate level[mean(SD)of 9.2±4.1 mmol/L vs 11.6±4.3 mmol/L;P<0.001]at admission than those not requiring ICU management of DKA(P<0.001).Patients in the ICU group had a longer LOS[median(IQR)of 4.2(2.7-7.1)d vs 2.0(1.0-3.9)d;P<0.001]and DKA duration[median(IQR)of 24(13-37)h vs 15(19-24)h,P<0.001]than those not requiring ICU admission.In the multivariate logistic regression analysis model,age,Asian ethnicity,concurrent coronavirus disease 2019(COVID-19)infection,DKA severity,DKA trigger,and NSTEMI were the main predicting factors for ICU admission.CONCLUSION In the largest tertiary center in Qatar,25%of all DKA patients required ICU admission.Older age,T2DM,newly onset DM,an infectious trigger of DKA,moderate-severe DKA,concurrent NSTEMI,and COVID-19 infection are some factors that predict ICU requirement in a DKA patient. 展开更多
关键词 Diabetic ketoacidosis Type 1 diabetes mellitus Type 2 diabetes mellitus Intensive care unit Critical care outcomes Length of stay
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一种Y型延迟荧光分子及其蓝光和绿光OLED应用 被引量:1
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作者 孙静 樊志杰 +2 位作者 杜纪宽 董海亮 王华 《发光学报》 EI CAS CSCD 北大核心 2024年第1期78-85,共8页
以噻吨酮作为受体、3,6-(二咔唑基)三咔唑作为给体设计合成了一种具有延迟荧光特性的Y型分子(TX-TCz)。模拟计算表明化合物HOMO和LUMO能级完全分离且在苯环上存在较小的重叠,有助于获得小的S1和T1的能级差ΔEST。随着溶剂极性的增加,化... 以噻吨酮作为受体、3,6-(二咔唑基)三咔唑作为给体设计合成了一种具有延迟荧光特性的Y型分子(TX-TCz)。模拟计算表明化合物HOMO和LUMO能级完全分离且在苯环上存在较小的重叠,有助于获得小的S1和T1的能级差ΔEST。随着溶剂极性的增加,化合物发射峰发生明显的红移且由于电荷转移态和局域激发态的共存产生了双峰发射。在纯膜中TX-TCz的发射峰位于513 nm,量子产率为11.5%。基于低温下荧光和磷光发射峰,计算得到化合物的ΔEST为0.03 eV,并且检测到µs级的寿命,说明化合物具有延迟荧光发射。与此同时,化合物展示了良好的热稳定性能和电化学性能,有助于制备高性能OLED器件。其在掺杂浓度为5%(wt)的器件中展示了良好的蓝光性能,发射峰位于463 nm,最大外量子效率为1.53%;在非掺杂器件中展示了良好的绿光发射(522 nm),最大外量子效率达到1.81%。 展开更多
关键词 OLED Y型分子 蓝光/绿光 延迟荧光
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2023年中国炼油工业发展状况及展望 被引量:2
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作者 费华伟 刘旭明 +1 位作者 王婧 高振宇 《国际石油经济》 2024年第4期43-48,103,共7页
2023年,中国炼油能力增长继续放缓,新增炼油能力1200万吨/年,总能力升至9.36亿吨/年,装置结构优化调整持续推进。2023年我国成品油需求快速反弹、市场整顿持续推进等利好因素推动炼油行业生产明显好转,多项主要生产经营指标显著回升。... 2023年,中国炼油能力增长继续放缓,新增炼油能力1200万吨/年,总能力升至9.36亿吨/年,装置结构优化调整持续推进。2023年我国成品油需求快速反弹、市场整顿持续推进等利好因素推动炼油行业生产明显好转,多项主要生产经营指标显著回升。国家政策为我国炼油行业高质量发展指明了路径,炼油企业持续推进绿色、低碳、数字化、智能化发展,并积极“走出去、引进来”,扩大合作。展望未来,2024年中国炼油能力将继续较快增长,但能力峰值基本显现,预计炼油能力峰值将在2027年左右出现;“十五五”期间,我国炼油能力过剩的压力有一定缓解,但不能掉以轻心,淘汰落后产能、调整产品结构、节能降碳等转型升级措施需长期推进。 展开更多
关键词 中国炼油工业 装置结构优化调整 减油增化 绿色低碳
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