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Influence of initial check, information exchange, final accuracy check, reaction information nursing on the psychology of elderly with lung cancer 被引量:2
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作者 Cui Jiang Jing Ma +1 位作者 Wen He Hai-Ying Zhang 《World Journal of Clinical Cases》 SCIE 2024年第4期737-745,共9页
BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychologi... BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychological problems.AIM To investigate the effectiveness of the initial check,information exchange,final accuracy check,reaction(IIFAR)information care model on the mental health status of elderly patients with lung cancer.METHODS This study is a single-centre study.We randomly recruited 60 elderly patients with lung cancer who attended our hospital from January 2021 to January 2022.These elderly patients with lung cancer were randomly divided into two groups,with the control group taking the conventional propaganda and education and the observation group taking the IIFAR information care model based on the conventional care protocol.The differences in psychological distress,anxiety and depression,life quality,fatigue,and the locus of control in psychology were compared between these two groups,and the causes of psychological distress were analyzed.RESULTS After the intervention,Distress Thermometer,Hospital Anxiety and Depression Scale(HADS)for anxiety and the HADS for depression,Revised Piper’s Fatigue Scale,and Chance Health Locus of Control scores were lower in the observation group compared to the pre-intervention period in the same group and were significantly lower in the observation group compared to those of the control group(P<0.05).After the intervention,Quality of Life Questionnaire Core 30(QLQ-C30),Internal Health Locus of Control,and Powerful Others Health Locus of Control scores were significantly higher in the observation and the control groups compared to the pre-intervention period in their same group,and QLQ-C30 scores were significantly higher in the observation group compared to those of the control group(P<0.05).CONCLUSION The IIFAR information care model can help elderly patients with lung cancer by reducing their anxiety and depression,psychological distress,and fatigue,improving their tendencies on the locus of control in psychology,and enhancing their life qualities. 展开更多
关键词 Initial check information exchange final accuracy check reaction information care model Lung cancer Mental health
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Spin wave resonance frequency in bilayer ferromagnetic films with the biquadratic exchange interaction
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作者 Xiaojie Zhang Yuting Wang +3 位作者 Yanqiu Chang Huan Wang Jianhong Rong Guohong Yun 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期607-613,共7页
The dependences of spin wave resonance(SWR)frequency on the surface anisotropy field,interface exchange coupling,symmetry,biquadratic exchange(BQE)interaction,film thickness,and the external magnetic field in bilayer ... The dependences of spin wave resonance(SWR)frequency on the surface anisotropy field,interface exchange coupling,symmetry,biquadratic exchange(BQE)interaction,film thickness,and the external magnetic field in bilayer ferromagnetic films are theoretically analyzed by employing the linear spin wave approximation and Green’s function method.A remarkable increase of SWR frequency,except for energetically lower two modes,can be obtained in our model that takes the BQE interaction into account.Again,the effect of the external magnetic field on SWR frequency can be increased by increasing the biquadratic to interlayer exchange ratio.It has been identified that the BQE interaction is of utmost importance in improving the SWR frequency of the bilayer ferromagnetic films.In addition,for bilayer ferromagnetic films,the frequency gap between the energetically highest mode and lowest mode is found to increase by increasing the biquadratic to interlayer exchange ratio and film thickness and destroying the symmetry of the system.These results can be used to improve the understanding of magnetic properties in bilayer ferromagnetic films and thus may have prominent implications for future magnetic devices. 展开更多
关键词 spin wave resonance frequency biquadratic exchange interaction interface exchange coupling surface anisotropy
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Scandium recovery from raffinate copper leach solution as potential new source with ion exchange method 被引量:3
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作者 H.HAJMOHAMMADI A.H.JAFARI M.ESKANDARI NASAB 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第11期3103-3113,共11页
Raffinate copper leach solution of the Iran Sarcheshmeh copper complex has up to 3 mg/L scandium(Sc),which is significantly better than many existing sources,making it a possible source for the recovery of Sc using th... Raffinate copper leach solution of the Iran Sarcheshmeh copper complex has up to 3 mg/L scandium(Sc),which is significantly better than many existing sources,making it a possible source for the recovery of Sc using the ion exchange method.Visual Minteq software was employed to ascertain the ionic species likely to be formed under operational conditions in the mine and for selecting the suitable ion exchange resin.The cationic resin thus chosen was employed statically with ions-bearing synthesized solutions and statically/dynamically for actual copper mining raffinate solution.Room temperature and pH of 1.5 showed the highest Sc adsorption.The dynamic tests established the full saturation of the resin at 450 BV of the raffinate solution flow.Using sodium carbonate for elution,desorption of Sc,Y and Ce from the resin during static elution tests at constant duration was higher than that of Fe,Al and Cu.The results from the dynamic tests followed similar trends for the priority and the extent of the elution process.Desorption results from specimens of dynamic tests show a 60:1 concentration ratio leading to a 186 mg/L Sc-rich solution. 展开更多
关键词 SCANDIUM ion exchange sorption DESORPTION copper leach solution
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Anion exchange membranes with a semi-interpenetrating polymer network using 1,6-dibromohexane as bifunctional crosslinker
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作者 Aijie Li Zhanliang Wang +6 位作者 Zhihao Si Lu Lu Peipei Huang Jinhong Liu Songyuan Yao Peiyong Qin Xinmiao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期199-208,共10页
An anion exchange membrane(AEM)is generally expected to possess high ion exchange capacity(IEC),low water uptake(WU),and high mechanical strength when applied to electrodialysis desalination.Among different types of A... An anion exchange membrane(AEM)is generally expected to possess high ion exchange capacity(IEC),low water uptake(WU),and high mechanical strength when applied to electrodialysis desalination.Among different types of AEMs,semi-interpenetrating polymer networks(SIPNs)have been suggested for their structural superiorities,i.e.,the tunable local density of ion exchange groups for IEC and the restrained leaching of hygroscopic groups by insolubility for WU.Unfortunately,the conventional SIPN AEMs still struggle to balances IEC,WU,and mechanical strength simultaneously,due to the lack of the compact crosslinking region.In this work,we proposed a novel SIPN structure of polyvinylidene difluoride/polyvinylimidazole/1,6-dibromohexane(PVDF/PVIm/DBH).On the one hand,DBH with two cationic groups of imidazole groups are introduced to enhance the ion conductivity,which is different from the conventional monofunctional modifier with only one cationic group.On the other hand,DBH has the ability to bridge with PVIm,where the mechanical strength of the resulting AEM is increased by the increase of crosslinking degree.Results show that a low WU of 38.1%to 62.6%,high IEC of 2.12—2.22 mmol·g^(-1),and excellent tensile strength of 3.54—12.35 MPa for PVDF/PVIm/DBH membrane are achieved.This work opens a new avenue for achieving the high-quality AEMs. 展开更多
关键词 Anion exchange membrane Polyvinylidene difluoride ELECTRODIALYSIS Semi-interpenetrating polymer networks
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State-selective charge exchange cross sections in collisions of highly-charged sulfur ions with helium and molecular hydrogen
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作者 朱小龙 崔述成 +9 位作者 邢大地 徐佳伟 B.Najjari 赵冬梅 郭大龙 高永 张瑞田 苏茂根 张少锋 马新文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期29-33,共5页
The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first ti... The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091. 展开更多
关键词 highly charged sulfur ion charge exchange state-selective cross sections COLTRIMS
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Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains
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作者 Weiting Gao Xuelang Gao +2 位作者 Qiugen Zhang Aimei Zhu Qinglin Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期324-335,I0008,共13页
Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological st... Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological structure and forming unblocked ion pathways in AEMs for fast ion transport.Fluorination of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine groups.However,their electronic effect on the alkaline stability of side chains and membranes is rarely reported.Here,fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane properties.The poly(binaphthyl-co-p-terphenyl piperidinium)AEM(QBNp TP)has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho-and meta-terphenyl based AEMs.Importantly,by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone,the prepared AEM(QBNp TP-QFC)presents an enhanced conductivity(150.6 m S cm^(-1))and a constrained swelling at 80℃.The electronic effect of fluorinated side chains is contemplated by experiments and simulations.The results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms,increasing OH^(-)attack on the C atom and improving the stability of piperidinium cations.Hence QBNp TP-QFC possesses a robust alkaline stability at 80℃(95.3%conductivity retention after testing in 2 M Na OH for 2160 h).An excellent peak power density of 1.44 W cm^(-2)and a remarkable durability at 80℃(4.5%voltage loss after 100 h)can be observed. 展开更多
关键词 Anion exchange membranes Backbone structure Fluorinated side chain Alkaline stability
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Atomically Adjustable Rhodium Catalyst Synthesis with Outstanding Mass Activity via Surface-Li mi ted Cation Exchange
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作者 Hak Hyeon Lee Dong Su Kim +3 位作者 Swagotom Sarker Ji Hoon Choi Ho Seong Lee Hyung Koun Cho 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期83-92,共10页
Rh has been widely studied as a catalyst for the promising hydrazine oxidation reaction that can replace oxygen evolution reactions for boosting hydrogen production from hydrazine-containing wastewater.Despite Rh bein... Rh has been widely studied as a catalyst for the promising hydrazine oxidation reaction that can replace oxygen evolution reactions for boosting hydrogen production from hydrazine-containing wastewater.Despite Rh being expensive,only a few studies have examined its electrocatalytic mass activity.Herein,surface-limited cation exchange and electrochemical activation processes are designed to remarkably enhance the mass activity of Rh.Rh atoms were readily replaced at the Ni sites on the surface of NiOOH electrodes by cation exchange,and the resulting RhOOH compounds were activated by the electrochemical reduction process.The cation exchange-derived Rh catalysts exhibited particle sizes not exceeding 2 nm without agglomeration,indicating a decrease in the number of inactive inner Rh atoms.Consequently,an improved mass activity of 30 A mg_(Rh)^(-1)was achieved at 0.4 V versus reversible hydrogen electrode.Furthermore,the two-electrode system employing the same CE-derived Rh electrodes achieved overall hydrazine splitting over 36 h at a stable low voltage.The proposed surface-limited CE process is an effective method for reducing inactive atoms of expensive noble metal catalysts. 展开更多
关键词 cation exchange synthesis electrochemical metallization hydrazine oxidation reaction mass activity rhodium catalyst
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Combining reinforcement learning with mathematical programming:An approach for optimal design of heat exchanger networks
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作者 Hui Tan Xiaodong Hong +4 位作者 Zuwei Liao Jingyuan Sun Yao Yang Jingdai Wang Yongrong Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期63-71,共9页
Heat integration is important for energy-saving in the process industry.It is linked to the persistently challenging task of optimal design of heat exchanger networks(HEN).Due to the inherent highly nonconvex nonlinea... Heat integration is important for energy-saving in the process industry.It is linked to the persistently challenging task of optimal design of heat exchanger networks(HEN).Due to the inherent highly nonconvex nonlinear and combinatorial nature of the HEN problem,it is not easy to find solutions of high quality for large-scale problems.The reinforcement learning(RL)method,which learns strategies through ongoing exploration and exploitation,reveals advantages in such area.However,due to the complexity of the HEN design problem,the RL method for HEN should be dedicated and designed.A hybrid strategy combining RL with mathematical programming is proposed to take better advantage of both methods.An insightful state representation of the HEN structure as well as a customized reward function is introduced.A Q-learning algorithm is applied to update the HEN structure using theε-greedy strategy.Better results are obtained from three literature cases of different scales. 展开更多
关键词 Heat exchanger network Reinforcement learning Mathematical programming Process design
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Synthesis of indirect work exchange networks considering both isothermal and adiabatic process together with exergy analysis 被引量:2
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作者 Yu Zhuang Linlin Liu +1 位作者 Lei Zhang Jian Du 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1644-1652,共9页
In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In co... In this paper, an efficient methodology for synthesizing the indirect work exchange networks(WEN) considering isothermal process and adiabatic process respectively based on transshipment model is first proposed. In contrast with superstructure method, the transshipment model is easier to obtain the minimum utility consumption taken as the objective function and more convenient for us to attain the optimal network configuration for further minimizing the number of units. Different from division of temperature intervals in heat exchange networks,different pressure intervals are gained according to the maximum compression/expansion ratio in consideration of operating principles of indirect work exchangers and the characteristics of no pressure constraints for stream matches. The presented approach for WEN synthesis is a linear programming model applied to the isothermal process, but for indirect work exchange networks with adiabatic process, a nonlinear programming model needs establishing. Additionally, temperatures should be regarded as decision variables limited to the range between inlet and outlet temperatures in each sub-network. The constructed transshipment model can be solved first to get the minimum utility consumption and further to determine the minimum number of units by merging the adjacent pressure intervals on the basis of the proposed merging methods, which is proved to be effective through exergy analysis at the level of units structures. Finally, two cases are calculated to confirm it is dramatically feasible and effective that the optimal WEN configuration can be gained by the proposed method. 展开更多
关键词 Work exchange networks Transshipment model Adiabatic process Exergy analysis Isothermal process Work cascade
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Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions
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作者 Xue-Ping Du Guang-Lei Yu +3 位作者 Ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1333-1345,共13页
The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper stud... The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions. 展开更多
关键词 Spiral-wound heat exchanger Sloshing conditions Two-phase flow MULTI-COMPONENT Heat and mass transfer
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CFD-Based Simulation and Analysis of Hydrothermal Aspects in Solar Channel Heat Exchangers with Various Designed Vortex Generators 被引量:2
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作者 Mohamed Salmi Younes Menni +3 位作者 Ali J.Chamkha HouariAmeur Rachid Maouedj Ahmed Youcef 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期147-173,共27页
The hydrothermal behavior of air inside a solar channel heat exchanger equipped with various shaped ribs is analyzed numerically.The bottom wall of the exchanger is kept adiabatic,while a constant value of the tempera... The hydrothermal behavior of air inside a solar channel heat exchanger equipped with various shaped ribs is analyzed numerically.The bottom wall of the exchanger is kept adiabatic,while a constant value of the temperature is set at the upper wall.The duct is equipped with a flat rectangular fin on the upper wall and an upstream V-shaped baffle on the lower wall.Furthermore,five hot wall-attached rib shapes are considered:trapezoidal,square,triangular pointing upstream(type Ⅰ),triangular pointing downstream(type Ⅱ),and equilateral-triangular(type Ⅲ)cross sections.Effects of the flow rates are also inspected for various Reynolds numbers in the turbulent regime(1.2×10^(4)-3.2×10^(4)).The highest performance(η)value is given for the Ⅱ-triangular rib case in all Re values,while the square-shaped ribs show a significant decrease in the η along the achieved Re range.The η value at Remax is 2.567 for the Ⅱ-triangular roughness case.Compared with the other simulated cases,this performance is decreased by about 3.768%in the case of Ⅰ-triangular ribs,15.249% in the case of Ⅲ-triangular ribs,20.802% in the case of trapezoidal ribs,while 27.541% in the case of square ribs,at the same Remax.Also,a comparison ismade with air-heat exchangers that have non-rough walls and contain cross-shaped VGs presented previously,in order to highlight the effectiveness of the rough surface presence in the baffled and finned channels.The obtained results indicated that the triangular-shaped rib(type Ⅱ)has the most significant hydrothermal behavior than the other cases.This indicates the necessity of roughness heat transfer surfaces for finned and baffled channels to improve significantly the performance of the air-heat exchangers they contain. 展开更多
关键词 CFD heat exchanger vortex generators RIBS hydrothermal aspects
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Simulating the Turbulent Hydrothermal Behavior of Oil/MWCNT Nanofluid in a Solar Channel Heat Exchanger Equipped with Vortex Generators 被引量:2
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作者 Rachid Maouedj Younes Menni +3 位作者 Mustafa Inc Yu-Ming Chu Houari Ameur Giulio Lorenzini 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第3期855-889,共35页
Re-engineering the channel heat exchangers(CHEs)is the goal of many recent studies,due to their great importance in the scope of energy transport in various industrial and environmental fields.Changing the internal ge... Re-engineering the channel heat exchangers(CHEs)is the goal of many recent studies,due to their great importance in the scope of energy transport in various industrial and environmental fields.Changing the internal geometry of the CHEs by using extended surfaces,i.e.,VGs(vortex generators),is the most common technique to enhance the efficiency of heat exchangers.This work aims to develop a newdesign of solar collectors to improve the overall energy efficiency.The study presents a new channel design by introducing VGs.The FVM(finite volume method)was adopted as a numerical technique to solve the problem,with the use of Oil/MWCNT(oil/multi-walled carbon nano-tubes)nanofluid to raise the thermal conductivity of the flow field.The study is achieved for a Re number ranging from12×10^(3) to 27×10^(3),while the concentration(φ)of solid particles in the fluid(Oil)is set to 4%.The computational results showed that the hydrothermal characteristics depend strongly on the flow patterns with the presence of VGs within the CHE.Increasing the Oil/MWCNT rates with the presence of VGs generates negative turbulent velocities with high amounts,which promotes the good agitation of nanofluid particles,resulting in enhanced great transfer rates. 展开更多
关键词 Channel heat exchanger FORCED-CONVECTION Oil/MWCNT nanofluid CFD vortex generators
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Petrology of Spinel-Lherzolite Xenoliths from Mazéléand Others Northen Xenoliths Localities of Cameroon Volcanic Line: Exchange Reactions and Equilibrium State
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作者 Nguihdama Dagwai Kamgang Pierre +2 位作者 Mbowou Gbambié Isaac Bertrand Chazot Gilles Ngounouno Ismaïla 《Open Journal of Geology》 CAS 2024年第5期629-653,共25页
The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki... The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki, Mazélé in the NE of Ngaoundéré, Tello and Ganguiré in the SE of Ngaoundéré and Likok, locality located in the west of Ngaoundé). The peridotite enclaves of the above localities show restricted mineralogical variation. Most are four-phase spinel-lherzolites, indicating that this is the main lithology that forms the lithospheric mantle below the shallow zone. No traces of garnet or primary plagioclase were detected, which strongly limits the depth range from which the rock fragments were sampled. The textures and the wide equilibrium temperatures (884˚C - 1115˚C) indicate also entrainment of lherzolite xenoliths from shallow depths within the lithosphere and the presence of mantle diapirism. The exchange reactions and equilibrium state established in this work make it possible to characterize the chemical composition of the upper mantle of each region and test the equilibrium state of the phases between them. Variations of major oxides and incompatible elemental concentrations in clinopyroxene indicate a primary control by partial melting. The absence of typical “metasomatic” minerals, low equilibration temperatures and enriched LREE patterns indicate that the upper mantle below septentrional crust of Cameroun underwent an event of cryptic metasomatic enrichment prior to partial melting. The distinctive chemical features, LREE enrichment, strong U, Ce and Pr, depletion relative to Ba, Nb, La, Pb, and T, fractionation of Zr and Hf and therefore ligh high Zr/Hf ratio, low La/Yb, Nb/La and Ti/Eu are all results of interaction of refractory peridotite residues with carbonatite melts. 展开更多
关键词 XENOLITHS Upper Mantle Northern Region Adamawa Cameroon Volcanic Line exchange Reaction
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Air-Side Heat Transfer Performance Prediction for Microchannel Heat Exchangers Using Data-Driven Models with Dimensionless Numbers
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作者 Long Huang Junjia Zou +2 位作者 Baoqing Liu Zhijiang Jin Jinyuan Qian 《Frontiers in Heat and Mass Transfer》 EI 2024年第6期1613-1643,共31页
This study explores the effectiveness of machine learning models in predicting the air-side performance of microchannel heat exchangers.The data were generated by experimentally validated Computational Fluid Dynam-ics... This study explores the effectiveness of machine learning models in predicting the air-side performance of microchannel heat exchangers.The data were generated by experimentally validated Computational Fluid Dynam-ics(CFD)simulations of air-to-water microchannel heat exchangers.A distinctive aspect of this research is the comparative analysis of four diverse machine learning algorithms:Artificial Neural Networks(ANN),Support Vector Machines(SVM),Random Forest(RF),and Gaussian Process Regression(GPR).These models are adeptly applied to predict air-side heat transfer performance with high precision,with ANN and GPR exhibiting notably superior accuracy.Additionally,this research further delves into the influence of both geometric and operational parameters—including louvered angle,fin height,fin spacing,air inlet temperature,velocity,and tube temperature—on model performance.Moreover,it innovatively incorporates dimensionless numbers such as aspect ratio,fin height-to-spacing ratio,Reynolds number,Nusselt number,normalized air inlet temperature,temperature difference,and louvered angle into the input variables.This strategic inclusion significantly refines the predictive capabilities of the models by establishing a robust analytical framework supported by the CFD-generated database.The results show the enhanced prediction accuracy achieved by integrating dimensionless numbers,highlighting the effectiveness of data-driven approaches in precisely forecasting heat exchanger performance.This advancement is pivotal for the geometric optimization of heat exchangers,illustrating the considerable potential of integrating sophisticated modeling techniques with traditional engineering metrics. 展开更多
关键词 Machine learning microchannel heat exchangers heat transfer data-driven modeling computational fluid dynamics
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A numerical study on heat transfer enhancement and design of a heat exchanger with porous media in continuous hydrothermal flow synthesis system 被引量:2
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作者 Pedram Karimi Pour-Fard Ebrahim Afshari +1 位作者 Masoud Ziaei-Rad Shahed Taghian-Dehaghani 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1352-1359,共8页
The aim of this study is to use a new configuration of porous media in a heat exchanger in continuous hydrothermal flow synthesis(CHFS)system to enhance the heat transfer and minimize the required length of the heat e... The aim of this study is to use a new configuration of porous media in a heat exchanger in continuous hydrothermal flow synthesis(CHFS)system to enhance the heat transfer and minimize the required length of the heat exchanger.For this purpose,numerous numerical simulations are performed to investigate performance of the system with porous media.First,the numerical simulation for the heat exchanger in CHFS system is validated by experimental data.Then,porous media is added to the system and six different thicknesses for the porous media are examined to obtain the optimum thickness,based on the minimum required length of the heat exchanger.Finally,by changing the flow rate and inlet temperature of the product as well as the cooling water flow rate,the minimum required length of the heat exchanger with porous media for various inlet conditions is assessed.The investigations indicate that using porous media with the proper thickness in the heat exchanger increases the cooling rate of the product by almost 40% and reduces the required length of the heat exchanger by approximately 35%.The results also illustrate that the most proper thickness of the porous media is approximately equal to 90% of the product tube's thickness.Results of this study lead to design a porous heat exchanger in CHFS system for various inlet conditions. 展开更多
关键词 Continuous hydrothermal flow synthesis Heat exchanger Heat transfer enhancement Porous media Numerical simulation
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Recent progress of antipoisoning catalytic materials for high temperature proton exchange membrane fuel cells doped with phosphoric acid
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作者 Dongping Xue Jia-Nan Zhang 《Industrial Chemistry & Materials》 2024年第2期173-190,共18页
High-temperature proton exchange membrane fuel cells(HT-PEMFCs)have the unique advantages of fast electrode reaction kinetics,high CO tolerance,and simple water and thermal management at their operating temperature(12... High-temperature proton exchange membrane fuel cells(HT-PEMFCs)have the unique advantages of fast electrode reaction kinetics,high CO tolerance,and simple water and thermal management at their operating temperature(120-300℃),which can effectively solve the hydrogen source problem and help achieve the dual-carbon goal.The catalysts in HT-PEMFCs are mainly Pt-based catalysts,which have good catalytic activity in the oxygen reduction reaction(ORR)and hydrogen oxidation reaction(HOR).However,in HT-PEMFCs,the high load of platinum-based catalysts to alleviate the limitation of strong adsorption of phosphoric acid(PA)on the platinum surface on activity expression leads to high cost,insufficient activity,decreased activity under long-term operation and carrier corrosion.The present review mainly summarizes the latest research progress of HT-PEMFCs catalysts,systematically analyzes the application of precious metal and non-precious metal catalysts in HT-PEMFCs,and unveils the structure-activity relationship and anti-PA poisoning mechanism.The current challenges and opportunities faced by HT-PEMFCs are discussed,as well as possible future solutions.It is believed that this review can provide some inspiration for the future development of high-performance HT-PEMFC catalysts. 展开更多
关键词 High-temperature proton exchange membrane fuel cells Cathodic oxygen reduction Anti-phosphoric acid poisonous Pt group metal catalysts Non-precious metal catalysts
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FREE ALKALI RECOVERY FROM NaOH LEACHING LIQUOR OF TUNGSTEN ORE BY ELECTROLYSIS WITH ION-EXCHANGE MEMBRANE
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作者 Guiqing Zhang Qixiu Zhang 《Journal of Central South University》 SCIE EI CAS 1998年第2期23-26,共4页
Caustic soda leaching liquor of tungsten ore always contains a certain amount of free alkali. General method of removing free alkali in the liquor is to neutralize it by inorganic acid. A new method, i.e. applying ele... Caustic soda leaching liquor of tungsten ore always contains a certain amount of free alkali. General method of removing free alkali in the liquor is to neutralize it by inorganic acid. A new method, i.e. applying electrolysis with ion exchange membrane to recover free alkali from caustic soda leaching liquor of tungsten ore, was proposed in the paper. In the electrolysis cell the effective area of membrane is 100 mm×100 mm, the anode is β PbO 2 plated at screen of titanium net, the cathode is active nickel plated at screen of stainless steel net, and the membrane is a kind of perfluorsulphonic acid membrane. Some effect factors of electrolysis process including the NaOH concentration in anolyte and catholyte, distance between electrodes, temperature, current density, are investigated. The results show that, by choosing proper operating condition, the specific energy consumption can be controlled within 2 kWh·kg -1 NaOH. Electrolysis with ion exchange membrane can not only recover free alkali from caustic soda leaching liquor, reduce the consumption of inorganic acid, but also utilize the hydrogen gas produced in the process to produce tungsten powder. 展开更多
关键词 ion exchange membrane ELECTROLYSIS tungsten CAUSTIC SODA
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Mao Zedong and His Ideas on Chinese Cultural Exchange with Other Nations
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《China & The World Cultural Exchange》 1993年第6期4-7,共4页
MAO Zedong,a leadingstatesman and ideologistof the twentieth century,rarely went abroad when overseeingaffairs of state in China.He had,nevertheless,a broad knowledge ofmany foreign ideas and civilizations,and saw the... MAO Zedong,a leadingstatesman and ideologistof the twentieth century,rarely went abroad when overseeingaffairs of state in China.He had,nevertheless,a broad knowledge ofmany foreign ideas and civilizations,and saw the wisdom in the ex-change of ideas between China andother countries.He personally in-volved himself in many of theseprojects to further the world’sknowledge of China,her relation-ships with the outside world,mod- 展开更多
关键词 himself WISDOM exchangeS outside AMERICANS rarely WRITER African visited PRIDE
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Separation of macro amounts of tungsten and molybdenum by ion exchange with D309 resin 被引量:14
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作者 卢晓颖 霍广生 廖春华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第9期3008-3013,共6页
Based on the difference in tendency to polymerize between tungsten and molybdenum, a new method using D309 resin was propounded. The batch tests indicate that the optimum pH value and contact time for the separation a... Based on the difference in tendency to polymerize between tungsten and molybdenum, a new method using D309 resin was propounded. The batch tests indicate that the optimum pH value and contact time for the separation are 7.0 and 4 h respectively, the maxium separation factor of W and Mo is 9.29. And the experimental resules show that isothermal absorbing tungsten and molybdenum belongs to Langmuir model and Freundlich model respectively, and the absorbing kinetics for tungsten is controlled by intra-particle diffusion. With a solution containing 70 g/L WO3 and 28.97 g/L Mo, the effluent with a mass ratio of Mo to WO3 of 76 and the eluate with a mass ratio of WO3 to Mo of 53.33 are obtained after column test. 展开更多
关键词 high concentrated tungstate and molybdenum solution ion exchange batch tests column tests
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Plasma exchange in patients with acute and acute-on-chronic liver failure: A systematic review 被引量:32
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作者 Eunice Xiang-Xuan Tan Min-Xian Wang +1 位作者 Junxiong Pang Guan-Huei Lee 《World Journal of Gastroenterology》 SCIE CAS 2020年第2期219-245,共27页
BACKGROUND Acute liver failure(ALF)and acute-on-chronic liver(ACLF)carry high short-term mortality rate,and may result from a wide variety of causes.Plasma exchange has been shown in a randomized control trial to impr... BACKGROUND Acute liver failure(ALF)and acute-on-chronic liver(ACLF)carry high short-term mortality rate,and may result from a wide variety of causes.Plasma exchange has been shown in a randomized control trial to improve survival in ALF especially in patients who did not receive a liver transplant.Other cohort studies demonstrated potential improvement in survival in patients with ACLF.AIM To assess utility of plasma exchange in liver failure and its effect on mortality in patients who do not undergo liver transplantation.METHODS Databases MEDLINE via PubMed,and EMBASE were searched and relevant publications up to 30 March,2019 were assessed.Studies were included if they involved human participants diagnosed with liver failure who underwent plasma exchange,with or without another alternative non-bioartificial liver assist device.RESULTS Three hundred twenty four records were reviewed,of which 62 studies were found to be duplicates.Of the 262 records screened,211 studies were excluded.Fifty-one articles were assessed for eligibility,for which 7 were excluded.Twenty-nine studies were included for ALF only,and 9 studies for ACLF only.Six studies included both ALF and ACLF patients.A total of 44 publications were included.Of the included publications,2 were randomized controlled trials,14 cohort studies,12 case series,16 case reports.All of three ALF studies which looked at survival rate or survival days reported improvement in outcome with plasma exchange.In two out of four studies where plasma exchange-based liver support systems were compared to standard medical treatment(SMT)for ACLF,a biochemical improvement was seen.Survival in the non-transplanted patients was improved in all four studies in patients with ACLF comparing plasma exchange vs SMT.Using the aforementioned studies,plasma exchange based therapy in ACLF compared to SMT improved survival in non-transplanted patients at 30 and 90-d with a pooled OR of 0.60(95%CI 0.46-0.77,P<0.01).CONCLUSION The level of evidence for use of high volume plasma exchange in selected ALF cases is high.Plasma exchange in ACLF improves survival at 30-and 90-d in nontransplanted patients.Further well-designed randomized control trials will need to be carried out to ascertain the optimal duration and amount of plasma exchange required and assess if the use of high volume plasma exchange can be extrapolated to patients with ACLF. 展开更多
关键词 Acute-on-chronic liver failure Acute liver failure PLASMAPHERESIS Plasma exchange Liver failure
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