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Critical reflection on the role of theater nurses in a multidisciplinary team for perioperative care in China 预览
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作者 Xiao Xiao She-Ning Zhu 《护理前沿(英文)》 CAS 2019年第1期27-33,共7页
Objective:The aim of this article is to reflect on the role of theater nurses in a multidisciplinary team,understand the factors that have influenced theater nurses’practice,and improve the authors’clinical practice... Objective:The aim of this article is to reflect on the role of theater nurses in a multidisciplinary team,understand the factors that have influenced theater nurses’practice,and improve the authors’clinical practice ultimately.Methods:The author used Smyth’s model to guide the process of reflection on the practice issue.Critical reflection,critical emancipatory theory,reflexivity,and critical social theory were used to help the author analyze the factors that have affected theater nurses’practice in the organization.Results:There are gaps between the espoused and enacted theories.A theater nurse’s practice is determined by multiple factors,such as political,structural,social,historical,cultural issues,and so on.The hierarchy of the health context could hinder possible changes in theater nurses’practice.To better understand our practice and implement transformation,we should shape a supportive environment,bear in mind the practice motto of“patient-centered”care,and improve our knowledge and reflection skills.Conclusions:Reflection plays a significant role in the advancing of practice among theater nurses and needs to be combined with clinical practice.To provide the best service of care to perioperative patients,a theater nurse should have an insightful understanding of the factors that have influenced her/his behaviors historically,socially,and culturally.By improving their critical reflection skills,practitioners could gain knowledge from experience. 展开更多
关键词 MULTIDISCIPLINARY team Smyth’s reflective framework REFLEXIVITY CRITICAL reflection CRITICAL emancipatory THEORY CRITICAL social THEORY task-oriented PERSON-CENTERED care
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Computational study of inverse ferrite spinels
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作者 A EL Maazouzi R Masrour +1 位作者 A Jabar M Hamedoun 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第5期305-311,共7页
The magnetic properties of inverse ferrite (Fe^3+)[Fe^3+Co^2+]O4^2-,(Fe^3+)[Fe^3+Cu^2+]O4^2,( Fe^3+)[Fe^3+Fe^2+]O4^2,and (Fe^3+)[Fe^3+Ni^2+]O4^2- spinels have been studied using Monte Carlo simulation.We have also cal... The magnetic properties of inverse ferrite (Fe^3+)[Fe^3+Co^2+]O4^2-,(Fe^3+)[Fe^3+Cu^2+]O4^2,( Fe^3+)[Fe^3+Fe^2+]O4^2,and (Fe^3+)[Fe^3+Ni^2+]O4^2- spinels have been studied using Monte Carlo simulation.We have also calculated the critical and Curie Weiss temperatures from the thermal magnetizations and inverse of magnetic susceptibilities for each system.Magnetic hysteresis cycles have been found for the four systems.Finally,we found the critical exponents associated with magnetization,magnetic susceptibility,and external magnetic field.Our results of critical and Curie Weiss temperatures are similar to those obtained by experiment results.The critical exponents are similar to those of known 3D-Ising model. 展开更多
关键词 INVERSE ferrites SPINELS Monte Carlo simulation CRITICAL and CURIE Weiss temperatures magnetic HYSTERESIS cycles CRITICAL EXPONENTS
Fujita-type Phenomenon of the Nonlocal Diffusion Equations with Localized Source
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作者 Lili YANG Zhongping LI 《数学研究及应用:英文版》 CSCD 2019年第2期171-180,共10页
In this paper, we investigate the Cauchy problem for the nonlocal diffusion system with localized source ut = J*u-u + a(x)v~p, v_t = J*v-v + a(x)u~q. We first prove that the Fujita curve is(pq)_c*-= 1+max{p+1, q+1}bas... In this paper, we investigate the Cauchy problem for the nonlocal diffusion system with localized source ut = J*u-u + a(x)v~p, v_t = J*v-v + a(x)u~q. We first prove that the Fujita curve is(pq)_c*-= 1+max{p+1, q+1}based on whether there exist global solutions, thatis, if 1 < pq(pq)_c,then every nonnegative solution blows up in finite time, but for pq >(pq)_c,there exist both global and non-global solutions to the problem. Furthermore, we establish the secondary critical curve on the space-decay of initial value at infinity. 展开更多
关键词 NONLOCAL diffusion system Fujita CRITICAL CURVE secondary CRITICAL CURVE global EXISTENCE BLOW-UP
A critical reflection on improving effective team communication 预览
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作者 Hua Yang 《护理前沿(英文)》 CAS 2019年第1期13-18,共6页
Objective:This paper aims at critically reflecting on the author’s personal experience in the context of communication within a nursing team and exploring relevant existing constraints with a view to improving practi... Objective:This paper aims at critically reflecting on the author’s personal experience in the context of communication within a nursing team and exploring relevant existing constraints with a view to improving practice and achieving more effective outcomes in team communication.Methods:Critical emancipatory reflection is used to evaluate and interpret the author’s practice.Smyth’s model serves as a framework to guide critical reflection step by step in this paper.Relevant theoretical perspectives help to make sense of the author’s performance in terms of team communication.Results:It is identified via emancipatory reflection that the author endorses the ideas of equality,respect,trust,and collaboration,which were formed and established during the process of professional socialization.However,different constraints,such as sociocultural,historical,political,and personal factors,impede the author from performing more effectively in terms of team communication.Reconstruction provides the author opportunities to take actions to rectify constraints and avoid the reemergence of previous situations in the future.Conclusions:Reflection is an effective way to gather knowledge and develop comprehensive understanding of practice.Alternative actions for effective team communication are recommended,including formulating ground rules for discussion,guiding nurses in the correct way,transforming conflicts within a team,being an active and reflective listener,and motivating nurses to actively create. 展开更多
关键词 CRITICAL emancipatory REFLECTION Smyth’s model TEAM communication CRITICAL social theory professional SOCIALIZATION CONSTRAINTS
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马克思对康德启蒙理性批判的现实超越 预览
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作者 王伞伞 《信阳师范学院学报:哲学社会科学版》 2019年第3期1-5,14共6页
启蒙运动自诞生之日起,就向人类昭示了其理性之内核,理性被置于崇高的地位。然而,在努力追求理性至上和自由的过程中,康德却提出了“什么是启蒙运动”的元问题,这无异于给沉醉于理性之中的人们带来了别样的风景。康德通过对理性的审慎... 启蒙运动自诞生之日起,就向人类昭示了其理性之内核,理性被置于崇高的地位。然而,在努力追求理性至上和自由的过程中,康德却提出了“什么是启蒙运动”的元问题,这无异于给沉醉于理性之中的人们带来了别样的风景。康德通过对理性的审慎反思以及对理性的批判厘清了人类理性的界限,并指出了人类理性的有限性,它不能超越经验和现象界达到对超验世界的关照。马克思则认为,自启蒙运动以来,人们力求达到的理性自由只是停留于观念上的自由,康德对于理性的批判并未触及现实社会的根基,康德只是在认识论上对人类的理性进行了限制。马克思立足于人类理性的有限性,把对理性的批判转向对资本主义社会现实的批判,其实践哲学实现了对理性批判范式的转变。 展开更多
关键词 启蒙运动 人类理性 马克思 康德 自由 先验 实践
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Asymptotic Behaviors for Critical Branching Processes with Immigration
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作者 Dou Dou LI Mei ZHANG 《数学学报:英文版》 SCIE CSCD 2019年第4期537-549,共13页
In this paper, we investigate the asymptotic behaviors of the critical branching process with immigration {Zn, n ≥ 0}. First we get some estimation for the probability generating function of Zn. Based on it, we get a... In this paper, we investigate the asymptotic behaviors of the critical branching process with immigration {Zn, n ≥ 0}. First we get some estimation for the probability generating function of Zn. Based on it, we get a large deviation for Zn+1/Zn. Lower and upper deviations for Zn are also studied. As a by-product, an upper deviation for max1≤i≤n Zi is obtained. 展开更多
关键词 CRITICAL branching PROCESS IMMIGRATION LARGE DEVIATIONS
Experimental Study on Dynamic Mechanical Properties of Sprayed Concrete-Surrounding Rock Combined Body 预览
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作者 Dongming Guo Pengyang Yan +2 位作者 Longfei Fan Yingshi Zhang Xiaoye Wang 《北京理工大学学报:英文版》 EI CAS 2019年第2期278-285,共8页
To investigate the dynamic response problem of the double medium formed by the adherence of sprayed concrete and surrounding rock in the tunnel,a split Hopkinson pressure bar of 75 mm in diameter was adopted at the ag... To investigate the dynamic response problem of the double medium formed by the adherence of sprayed concrete and surrounding rock in the tunnel,a split Hopkinson pressure bar of 75 mm in diameter was adopted at the ages of 3,7 and 10 d.Experimental results showed that dynamic compressive strength and dynamic increase factors(DIF)of the combined bodies increase with the strain rate.With the growth of strain rate,the critical strain of the combined bodies first increases,then deceases.Furthermore,the combined bodies of 3 d reveal the plastic property and brittle property for 7 d and 10 d when the strain rate is over 80/s.The failure characteristic of the sprayed concrete changes from tearing strain damage to crushing damage as the growth of strain rate,and the failure characteristic of rock presents the tensile failure mode as demonstrated by the scanning electron microscope(SEM). 展开更多
关键词 SPRAYED concrete-surrounding rock COMBINED BODY DYNAMIC compressive strength DYNAMIC increase factors critical strain failure modes
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数学思维批判性的培养初探 预览
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作者 张存堂 《滁州职业技术学院学报》 2019年第2期92-94,共3页
本文根据中学教学真实案例提出思维批判性与数学学习中思维批判性培养的必要性,并从学生的独立思考、反思、质疑能力三个方面进行剖析,探讨在数学教学中如何培养学生思维的批判性。
关键词 数学 思维 批判性
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Can Chinese Companies Still Invest in the United States? The Impact of FIRRMA 预览
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作者 Paul B. Edelberg 《美中法律评论:英文版》 2019年第1期12-20,共9页
The Foreign Investment Risk Review Act,or FIRRMA,signed by President Trump on August 13,2018,significantly expanded the scope of transactions involving foreign investment in U.S.companies that are covered by the natio... The Foreign Investment Risk Review Act,or FIRRMA,signed by President Trump on August 13,2018,significantly expanded the scope of transactions involving foreign investment in U.S.companies that are covered by the national security laws of the U.S.,commonly known as the CFIUS regime.Certain minority investments and certain technology-related investments may now need to be submitted to the Committee on Foreign Investment in the U.S.(CFIUS)for clearance.FIRRMA also implements an expedited filing process,which in some cases is mandatory,and expands the authority and enforcement tools of CFIUS.This new law in part targets China’s investments in the U.S.and its attempts to procure U.S.-based technology.This article discusses the new law and analyzes the implications of the law on Chinese investment in the U.S. 展开更多
关键词 CFIUS FIRRMA critical TECHNOLOGIES emerging and foundational TECHNOLOGIES MINORITY INVESTMENTS foreign ACQUISITIONS declarations national security
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A unified critical state model for geomaterials with an application to tunnelling 预览
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作者 Hai-Sui Yu Pei-Zhi Zhuang Pin-Qiang Mo 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第3期464-480,共17页
This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in ge... This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in geomechanics and geotechnical engineering.As a result,we have picked a topic that reflects two key research areas in which Professor E.T.Brown has made seminal contributions over a long and distinguished career.These two areas are concerned with the application of the critical state concept to modelling geomaterials and the analysis of underground excavation or tunnelling in geomaterials.Partially due to Professor Brown’s influence,the first author has also been conducting research in these two areas over many years.In particular,this paper aims to describe briefly the development of a unified critical state model for geomaterials together with an application to cavity contraction problems and tunnelling in soils. 展开更多
关键词 Critical state SOIL mechanics CONSTITUTIVE models Cavity CONTRACTION TUNNELLING in SOIL
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Stress dependence of the creep behaviors and mechanisms of a third-genegation Ni-based single crystal superalloy
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作者 Quanzhao Yue Lin Liu +5 位作者 Wenchao Yang Chuang He Dejian Sun Taiwen Huang Jun Zhang Hengzhi Fu 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第5期752-763,共12页
Elevated temperature creep behaviors at 1100℃ over a wide stress regime of 120-174 MPa of a thirdgeneration Ni-based single crystal superalloy were studied. With a reduced stress from 174 to 120 MPa, the creep life i... Elevated temperature creep behaviors at 1100℃ over a wide stress regime of 120-174 MPa of a thirdgeneration Ni-based single crystal superalloy were studied. With a reduced stress from 174 to 120 MPa, the creep life increased by a factor of 10.5, from 87 h to 907 h, presenting a strong stress dependence. A splitting phenomenon of the close-(about 100 nm) and sparse-(above 120 nm) spaced dislocation networks became more obvious with increasing stress. Simultaneously, ao<010> superdislocations with low mobil让ies were frequently observed under a lower stress to pass through γ precipitates by a combined slip and climb of two ao<110> superpartials or pure climb. However, ao<110> superdislocations with higher mobility were widely found under a higher stress, which directly sheared into y precipitates. Based on the calculated critical resolved shear stresses for various creep mechanisms, the favorable creep mechanism was systematically analyzed. Furthermore, combined with the microstructural evolutions during different creep stages, the dominant creep mechanism changed from the dislocation climbing to Orowan looping and precipitates shearing under a stress regime of 137-174MPa, while the dislocation dim bing mechanism was operative throughout the whole creep stage un der a stress of 120 MPa, resulting a superior creep performanee. 展开更多
关键词 NI-BASED single crystal SUPERALLOY CREEP Dislocation network Critical RESOLVED shear STRESS CREEP mechanism
液体敷料赛肤润预防危重患者失禁性皮炎的效果 预览
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作者 杨瑞红 《中国当代医药》 2019年第17期229-231,共3页
目的探讨液体敷料赛肤润预防危重患者失禁性皮炎(IAD)的效果。方法选取我院2017年9月~2018年12月接诊的100例危重且伴发IAD患者作为研究对象,根据患者入院ID号随机分为对照组和观察组,各50例。对照组采取便后温水清洗,观察组在对照组的... 目的探讨液体敷料赛肤润预防危重患者失禁性皮炎(IAD)的效果。方法选取我院2017年9月~2018年12月接诊的100例危重且伴发IAD患者作为研究对象,根据患者入院ID号随机分为对照组和观察组,各50例。对照组采取便后温水清洗,观察组在对照组的基础上采取液体敷料赛肤润进行喷、涂、擦治疗。比较两组患者预防后的临床效果、皮损程度及IAD发生率、发生时间。结果观察组的总有效率(98%)明显高于对照组(74%),差异有统计学意义(χ^2=11.960,P=0.005)。观察组患者的皮肤损伤发生率明显低于对照组,差异有统计学意义(χ^2=18.918,P=0.001)。观察组的IAD发生率为8.00%,明显低于对照组的30.00%,差异有统计学意义(P<0.05)。观察组的IAD发生时间为(3.13±0.77)d,明显短于对照组的(9.43±1.94)d,差异有统计学意义(P<0.05)。结论液体敷料赛肤润预防危重患者IAD的效果显著,能够有效预防排便失禁所致肛周皮肤损伤,改善患者的生活质量,值得临床应用及推广。 展开更多
关键词 赛肤润 预防 危重 失禁性皮炎 效果
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Chemometric identification of canonical metabolites linking critical process parameters to monoclonal antibody production during bioprocess development
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作者 Lijuan Shen Xu Yan +5 位作者 Lei Nie Wenyan Xu Shiwei Miao Haibin Wang H.Fai Poon Haibin Qu 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1171-1176,共6页
A deeper understanding of the biological events occurring when bioprocess parameters changed will be of great value in improving the monoclonal antibodies (mAbs) production. Design of experiment (DoE) was applied to i... A deeper understanding of the biological events occurring when bioprocess parameters changed will be of great value in improving the monoclonal antibodies (mAbs) production. Design of experiment (DoE) was applied to investigate the effect of process parameters (pH, temperature shift and dissolve oxygen (DO)) on protein titer. The key metabolites connecting the critical process parameters (CPPs) with monoclonal antibody production were identified by different chemometrics tools. Finally, the biological events of marker metabolites relating with titer improvement were concluded. pH and temperature shift were identified as CPPs that affect the target protein titer. A series of metabolites influenced by the altered CPPs and correlated with protein titer were screened by principal component analysis (PCA) and Pearson' correlation test. The marker metabolites and their pathways linking CPPs to target protein titer in different culture phases were summarized. Metabolomics and chemometrics are promising data-driven tools to shine light into the biological black box between the bioprocess parameters and process performance. 展开更多
关键词 CANONICAL METABOLITES CHEMOMETRICS Critical process PARAMETERS Metabolomics Protein TITER
Carbonate pore type characterization using a statistical inversion method 预览
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作者 LI Bonan 《世界地质:英文版》 2019年第1期21-28,共8页
For carbonate reservoirs, vertical pore type heterogeneity records regional depositional history. However, from the geophysics point of view, these microscopic characteristics cannot be described with conventional dat... For carbonate reservoirs, vertical pore type heterogeneity records regional depositional history. However, from the geophysics point of view, these microscopic characteristics cannot be described with conventional data-driven approaches. The author presents an upscale rock physics model which includes both modeling and inverting schemes in this study. According to the statistical comparability between lab measurements and well logs, the main idea is to study and utilize inherent statistical features in naturally occurred carbonate rocks. Firstly, using the critical porosity model as rock physical theory, relationships are built between pore structures and elastic responses. Furthermore, in logging data scale, key parameters are estimated through a statistical method, and thus pore types are classified. The methodology is successfully applied in the well YS1. It is believed that this method will be a promising tool on handing pore complexity and inversion uncertainty in carbonate reservoir exploration. 展开更多
关键词 CARBONATE RESERVOIRS rock PHYSICS modeling critical POROSITY BAYESIAN estimation
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Method for Predicting the Fatigue Life of Geometrically Discontinuous Structures Under Combined Bending and Torsion
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作者 Jianhui Liu Xuemei Pan +1 位作者 Yaobing Wei Youliang Wang 《固体力学学报:英文版》 SCIE EI CSCD 2019年第3期367-377,共11页
The fatigue damage model based on theory of damage mechanics is capable of predicting the fatigue life under multiaxial loading. Meanwhile, the application of critical plane method in the prediction of multiaxial fati... The fatigue damage model based on theory of damage mechanics is capable of predicting the fatigue life under multiaxial loading. Meanwhile, the application of critical plane method in the prediction of multiaxial fatigue life has made certain progress. According to the law of thermodynamics, a new damage evolution equation is developed in the present study to predict the fatigue life of geometrically discontinuous structure under tension-torsion loading based on damage mechanics and the critical plane method. The essence of this approach is tha t the st rain parame ter of the uniaxial nonlinear fatigue damage model is replaced with the equivalent strain, which consists of the releva nt parame ters of the critical plane. However, it is difficult to calculate the stress-strain status and the critical plane position of geometrically dis? continuous structure by theoretical methods because of the existence of stress concentration and the multiaxial nonproportional characteristics. Therefore, a new numerical simulation method is proposed to determine the critical plane of geometrically discontinuous structure under multiaxial loading by means of the finite element method and MATLAB software. The fatigue life of notched specimens subjected to combined bending and torsion is predicted using the proposed met hod, and the result is compared with t hose from the experimen ts and the Manson-Cfiffin law. The comparisons show that the proposed method is superior to the Manson-Coffin law and is capable of reproducing the experimental results reasonably when the geometry of the structure is complex. It completely meets the needs of engineering practice. 展开更多
关键词 Damage MECHANICS Critical PLANE METHOD Geometrically DISCONTINUOUS structure Finite element METHOD
Understanding human diseases using Drosophila
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作者 Jun-Yuan Ji Chun Han Wu-Min Deng 《遗传学报:英文版》 SCIE CAS CSCD 2019年第4期155-156,共2页
One of the major goals of biomedical research is to elucidate the causal relationships of critical factors involved in the initiation and progression of human diseases at the molecular and cellular levels. This knowle... One of the major goals of biomedical research is to elucidate the causal relationships of critical factors involved in the initiation and progression of human diseases at the molecular and cellular levels. This knowledge is required for developing effective treatments for major diseases including cancer, cardiovascular and metabolic diseases, as well as neurodegenerative diseases and neurological disorders. Because of their phylogenetic representations and relative ease of experimental manipulation, model organisms such as the budding yeast (Saccharomyces cerevisiae), the nematode worm (Caenorhabditis elegans), the fruit fly (Drosophila melanogaster'), the thale cress (Arabidopsis thaliana), the zebrafish (Danio rerio'), the frog (Xenopus laevis), and the mouse (Mus musculus}, have been extensively studied over the past century (Hedges, 2002;Muller and Grossniklaus, 2010;Dietrich et al., 2014). 展开更多
关键词 BIOMEDICAL research CAUSAL RELATIONSHIPS critical factors INVOLVED
Impact of recycling improvement on the life cycle of phosphorus
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作者 Mohammad El Wali Saeed Rahimpour Golroudbary Andrzej Kraslawski 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第5期1219-1229,共11页
Access to natural resources is increasingly more difficult and more costly, partly due to their economic significance and to continuous increase of their global consumption in the recent years. In the case of phosphor... Access to natural resources is increasingly more difficult and more costly, partly due to their economic significance and to continuous increase of their global consumption in the recent years. In the case of phosphorus (P), which is a critical raw material, geological distribution of its primary nonrenewable source (phosphate rock) is concentrated in particular regions leading to high supply risk of this raw material. In Europe (EU-28), where phosphate rock reserves are scarce, import of phosphorus has been the main source of supply. It means that Europe relies highly on the foreign exporters. From decision makers' perspective, recycling of phosphorus was taken into account as one of the possible solutions to decrease the dependence on imports and extraction of reserves. The question, however, is to what extent does the recycling of phosphorus help in reducing the reliance on typical supply resources? Hence, the main objective of this paper is to quantify the dynamic flow of phosphorus and show potential benefits of its recycling in Europe. This article presents a system dynamics model for representation of the element P flow and helps to quantify to what extent the recycled phosphorus could mitigate its criticality. Analysis of the results supports previous studies indicating the high reliance ofEU on P imports, estimating around 96% as the reliance percentage on imports. The results imply that improving P recycling has the potential to decrease the level of P imports to a certain extent, which may reach 79%. 展开更多
关键词 CRITICAL material PHOSPHORUS DYNAMIC MODELLING DYNAMIC simulation RECOVERY RECYCLING
Global Optimization of Polynomials over Real Algebraic Sets
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作者 WANG Chu YANG Zhi-Hong ZHI Lihong 《系统科学与复杂性学报:英文版》 SCIE EI CSCD 2019年第1期158-184,共27页
Let f, g1, ···, gs be polynomials in R[X1, ···, Xn]. Based on topological properties of generalized critical values, the authors propose a method to compute the global infimum f^* of f ov... Let f, g1, ···, gs be polynomials in R[X1, ···, Xn]. Based on topological properties of generalized critical values, the authors propose a method to compute the global infimum f^* of f over an arbitrary given real algebraic set V = {x ∈ Rn| g1(x) = 0, ···, gs(x) = 0}, where V is not required to be compact or smooth. The authors also generalize this method to solve the problem of optimizing f over a basic closed semi-algebraic set S = {x ∈ Rn| g1(x) ≥ 0, ···, gs(x) ≥ 0}. 展开更多
关键词 POLYNOMIAL optimization REAL ALGEBRAIC set GENERALIZED CRITICAL value
A Review of Methods of Critical Discourse Analysis (second edition) 预览
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作者 梁嘉齐 《海外英语》 2019年第8期123-124,共2页
This article gives an overview of Methods of Critical Discourse Analysis (second edition), which respectively introduces six approaches to do critical discourse analysis. Personal comments and suggestions on the book ... This article gives an overview of Methods of Critical Discourse Analysis (second edition), which respectively introduces six approaches to do critical discourse analysis. Personal comments and suggestions on the book are also presented. It is hoped that the article may help readers particularly who would want to grow and extent their interest in CDA better usher into the field. 展开更多
关键词 CRITICAL DISCOURSE Analysis REVIEW approach METHODS
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Novel application of PEG/SDS interaction as a wettability modifier of hydrophobic carbonate surfaces
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作者 Nasim Heydari Mahdi Asgari +1 位作者 Narjes Shojai Kaveh Zahra Fakhroueian 《石油科学:英文版》 SCIE CAS CSCD 2019年第2期318-327,共10页
Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of... Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol(PEG) with an ionic surfactant, sodium dodecyl sulphate(SDS),is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration(CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte(NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface. 展开更多
关键词 Sodium dodecyl sulphate (SDS)- Polyethylene GLYCOL (PEG)- WETTABILITY alteration Contact angle Critical aggregation concentration CARBONATE surface
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