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Direct Ethylene Purification from Cracking Gas via a Metal–Organic Framework Through Pore Geometry Fitting
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作者 Yang Chen Zhenduo Wu +6 位作者 Longlong Fan Rajamani Krishna Hongliang Huang Yi Wang Qizhao Xiong Jinping Li Libo Li 《Engineering》 SCIE EI CAS CSCD 2024年第10期84-92,共9页
The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied f... The direct one-step separation of polymer-grade C_(2)H_(4) from complex light hydrocarbon mixtures has high industrial significance but is very challenging.Herein,an ethylene-adsorption-weakening strategy is applied for precise regulation of the pore geometry of four tailor-made metal–organic frameworks(MOFs)with pillar-layered structures,dubbed TYUT-10/11/12/13.Based on its pore geometry design and functional group regulation,TYUT-12 exhibits exceptional selective adsorption selectivity toward C_(3)H_(8),C_(3)H_(6),C_(2)H_(6),C_(2)H_(2),and CO_(2) over C_(2)H_(4);its C_(2)H_(6)/C_(2)H_(4) adsorption selectivity reaches 4.56,surpassing the record value of 4.4 by Fe_(2)(O_(2))(dobdc)(dobdc^(4-)=2,5-dioxido-1,4-benzenedicarboxylate).The weak p–p stacking binding affinity toward C_(2)H_(4) in TYUT-12 is clearly demonstrated through a combination of neutron powder diffraction measurements and theoretical calculations.Breakthrough experiments demonstrate that C_(2)H_(4) can be directly obtained from binary,ternary,quaternary,and six-component light hydrocarbon mixtures with over 99.95%purity. 展开更多
关键词 Metal-organic frameworks Pore regulation Adsorptive separation One-step purification C_(2)H_(4)purification
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Fluid property identification of the Lower Cretaceous reservoirs with complex oil-water contacts in Deseo Basin,Chad
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作者 Xinxin Zhang Lianfeng Zhu +4 位作者 Tianjiao Wang Xiaokang Shi Bo Han Jian Shen Hailei Gao 《Energy Geoscience》 EI 2024年第1期89-98,共10页
Recently,exploration breakthroughs have been made in the Lower Cretaceous sandstone reservoirs in the Doseo Basin,but the identification of reservoir fluid property is difficult due to variable reservoir lithology,com... Recently,exploration breakthroughs have been made in the Lower Cretaceous sandstone reservoirs in the Doseo Basin,but the identification of reservoir fluid property is difficult due to variable reservoir lithology,complex oil-water contact within and faint responses of the oil zone,which causes the lower accuracy of reservoir fluid property identification with conventional mudlogging and wirelogging techniques.Applying the geochemical logging,fluorescent logging,mud logging and cutting logging technology,in combination with formation test data,this paper distinguishes the crude oil types,analyzes the logging response characteristics of oil zone after water washing,and establishes the interpretation charts and parameter standards for reservoir fluid properties.The crude oil can be divided into two types,namely viscous-heavy and thin-light,based on total hydrocarbon content and component concentration tested by mud logging,features of pyrolysis gas chromatogram and fluorescence spectroscopy.The general characteristics of oil layers experienced water washing include the decrease of total hydrocarbon content and component concentration from mud logging,the decrease of S1 and PS values from geochemical logging,the decrease of hydrocarbon abundance and absence of some light components in pyrolysis gas chromatogram,and the decrease of fluorescence area and intensity from fluorescence logging.According to crude oil types,the cross plots of S1 versus peak-baseline ratio,and the cross plots of rock wettability versus fluorescence area ratio are drawn and used to interpret reservoir fluid property.Meanwhile,the standards of reservoir fluid parameter are established combining with the parameters of PS and the parameters in above charts,and comprehensive multiparameter correlation in both vertical and horizontal ways is also performed to interpret reservoir fluid property.The application in the Doseo Basin achieved great success,improving interpretation ability of fluid property in the reservoir with complex oil-water contact,and also provided technical reference for the efficient exploration and development of similar reservoirs. 展开更多
关键词 Doseo Basin Reservoir interpretation oil-water contact Fluid property Crude oil type
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The application of cellulosic-based materials on interfacial solar steam generation for highly efficient wastewater purification: A review
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作者 Haroon A.M.Saeed Weilin Xu Hongjun Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期245-282,共38页
The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as m... The world's population is growing,leading to an increasing demand for freshwater resources for drinking,sanitation,agriculture,and industry.Interfacial solar steam generation(ISSG)can solve many problems,such as mitigating the power crisis,minimizing water pollution,and improving the purification and desalination of seawater,rivers/lakes,and wastewater.Cellulosic materials are a viable and ecologically sound technique for capturing solar energy that is adaptable to a range of applications.This review paper aims to provide an overview of current advancements in the field of cellulose-based materials ISSG devices,specifically focusing on their applications in water purification and desalination.This paper examines the cellulose-based materials ISSG system and evaluates the effectiveness of various cellulosic materials,such as cellulose nanofibers derived from different sources,carbonized wood materials,and two-dimensional(2D)and 3D cellulosic-based materials from various sources,as well as advanced cellulosic materials,including bacterial cellulose and cellulose membranes obtained from agricultural and industrial cellulose wastes.The focus is on exploring the potential applications of these materials in ISSG devices for water desalination,purification,and treatment.The function,advantages,and disadvantages of cellulosic materials in the performance of ISSG devices were also deliberated throughout our discussion.In addition,the potential and suggested methods for enhancing the utilization of cellulose-based materials in the field of ISSG systems for water desalination,purification,and treatment were also emphasized. 展开更多
关键词 CELLULOSIC MATERIALS PHOTOTHERMAL conversion process SOLAR STEAM GENERATION wastewater purification
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Purification of copper foils driven by single crystallization
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作者 寇金宗 赵孟泽 +10 位作者 李兴光 何梦林 杨方友 刘科海 成庆秋 任云龙 刘灿 付莹 吴慕鸿 刘开辉 王恩哥 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期506-511,共6页
High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current puri... High-purity copper(Cu) with excellent thermal and electrical conductivity, is crucial in modern technological applications, including heat exchangers, integrated circuits, and superconducting magnets. The current purification process is mainly based on the zone/electrolytic refining or anion exchange, however, which excessively relies on specific integrated equipment with ultra-high vacuum or chemical solution environment, and is also bothered by external contaminants and energy consumption. Here we report a simple approach to purify the Cu foils from 99.9%(3N) to 99.99%(4N) by a temperature-gradient thermal annealing technique, accompanied by the kinetic evolution of single crystallization of Cu.The success of purification mainly relies on(i) the segregation of elements with low effective distribution coefficient driven by grain-boundary movements and(ii) the high-temperature evaporation of elements with high saturated vapor pressure.The purified Cu foils display higher flexibility(elongation of 70%) and electrical conductivity(104% IACS) than that of the original commercial rolled Cu foils(elongation of 10%, electrical conductivity of ~ 100% IACS). Our results provide an effective strategy to optimize the as-produced metal medium, and therefore will facilitate the potential applications of Cu foils in precision electronic products and high-frequency printed circuit boards. 展开更多
关键词 purification copper foil thermal annealing technique single crystallization
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Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient
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作者 Guangxia Jin Yuxue Wu Feng Wei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期212-219,共8页
The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar co... The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC). 展开更多
关键词 Solvent gradient Twin-column recycling chromatography purification Minor component Natural products
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Characterization of Flame Retardancy and Oil-Water Separation Capacity of Superhydrophobic Silylated Melamine Sponges
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作者 Yongchun Liu Ni Qiao +7 位作者 Yanli Yang Yanchun Li Chunxiao He Siyang Wang Chengcheng Liu Ruixia Lei Wang Li Wenwen Gao 《Fluid Dynamics & Materials Processing》 EI 2024年第2期383-400,共18页
A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourie... A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efficiency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicflame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efficiency for oil in saturated aqueous solutions. 展开更多
关键词 METHYLTRICHLOROSILANE silylated melamine sponge(SMS) SUPERHYDROPHOBICITY absorption capacity oil-water separable efficiency flame retardancy
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Numerical Simulation of Oil-Water Two-Phase Flow in Low Permeability Tight Reservoirs Based on Weighted Least Squares Meshless Method
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作者 Xin Liu Kai Yan +3 位作者 Bo Fang Xiaoyu Sun Daqiang Feng Li Yin 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1539-1552,共14页
In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering comp... In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production. 展开更多
关键词 Weighted least squares method meshless method numerical simulation of low permeability tight reservoirs oil-water two-phase flow fracture half-length
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Research Progress on Purification Process, Content Determination and Pharmacological Action of Atractylodin
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作者 Xin SUN Jingwen WANG +1 位作者 Yang XI Chenghao JIN 《Asian Agricultural Research》 2024年第3期33-35,40,共4页
Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rh... Atractylodis Rhizoma comes from the dry rhizome of Atractylis lancea or Atractylodes chinensis in the Compositae family,and it is suitable for preventing and treating diseases such as cold,edema,night blindness and rheumatic arthralgia.Atractylodin is the main active component extracted and isolated from Atractylodis Rhizoma.A large number of studies have found that atractylodin has excellent drug activity in improving gastrointestinal emptying,anti-inflammation,inhibiting malignant tumor and reducing blood lipid.In this paper,the purification process and pharmacological activity of Atractylodin were summarized to provide a theoretical basis for basic research,clinical application and further development and utilization of atractylodin. 展开更多
关键词 ATRACTYLODIN PHARMACOLOGICAL action purification PROCESS CONTENT DETERMINATION
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Study of three-dimensional spatial diffuse discharge in contact electrode structure applied to air purification
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作者 Shuai XU Wenzheng LIU +3 位作者 Jiaying QIN Yiwei SUN Xitao JIANG Qi QI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第10期73-81,共9页
In this work,based on the role of pre-ionization of the non-uniform electric field and its effect of reducing the collisional ionization coefficient,a diffuse dielectric barrier discharge plasma is formed in the open ... In this work,based on the role of pre-ionization of the non-uniform electric field and its effect of reducing the collisional ionization coefficient,a diffuse dielectric barrier discharge plasma is formed in the open space outside the electrode structure at a lower voltage by constructing a three-dimensional non-uniform spatial electric field using a contact electrode structure.The air purification study is also carried out.Firstly,a contact electrode structure is constructed using a three-dimensional wire electrode.The distribution characteristics of the spatial electric field formed by this electrode structure are analyzed,and the effects of the non-uniform electric field and the different angles of the vertical wire on the generation of three-dimensional spatial diffuse discharge are investigated.Secondly,the copper foam contact electrode structure is constructed using copper foam material,and the effects of different mesh sizes on the electric field distribution are analyzed.The results show that as the mesh size of the copper foam becomes larger,a strong electric field region exists not only on the surface of the insulating layer,but also on the surface of the vertical wires inside the copper foam,i.e.,the strong electric field region shows a three-dimensional distribution.Besides,as the mesh size increases,the area of the vertical strong electric field also increases.However,the electric field strength on the surface of the insulating layer gradually decreases.Therefore,the appropriate mesh size can effectively increase the discharge area,which is conducive to improving the air purification efficiency.Finally,a highly permeable stacked electrode structure of multilayer wire-copper foam is designed.In combination with an ozone treatment catalyst,an air purification device is fabricated,and the air purification experiment is carried out. 展开更多
关键词 dielectric barrier discharge three-dimensional spatial discharge atmospheric pressure air diffusion discharge air purification
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An Affordable and Easily Accessible Approach for Acrylonitrile Monomer Purification through a Simple Column Technique
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作者 Rawdah Whba Mohd Sukor Su’ait Azizan Ahmad 《Journal of Materials Science and Chemical Engineering》 2024年第4期18-28,共11页
This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impuri... This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impurities. The primary method for monomer purification, like acrylonitrile (AN), is the distillation technique. However, this technique is unsafe and hard to set up or handle. A straightforward, risk-free, low-cost method like the column technique resolves these issues. A simple column technique demonstrated the successful execution of purifying AN. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analyses confirmed that AN was successfully purified, with purity reaching 99.8%. FTIR spectra revealed changes in the position and intensity of the stretching vibration peaks after purification. Also, the functional groups of the inhibitor monomethyl ether of hydroquinone (MeHQ) were undetected after purification. Furthermore, after purification, NMR spectra revealed the absence of aromatic protons and carbons associated with MeHQ. In conclusion, the column technique is a successful and inexpensive way to purify AN monomers. This makes it useful for a wide range of applications, especially in polymerization reactions where MeHQ needs to be removed to prevent self-polymerization during the initiation process. 展开更多
关键词 Liquid Monomers ACRYLONITRILE purification Inhibitor Simple Column
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Superwetting Ag/α-Fe_(2)O_(3) anchored mesh with enhanced photocatalytic and antibacterial activities for efficient water purification
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作者 Jiakai Li Changpeng Lv +5 位作者 Jiajia Song Xiaoling Zhang Xizhen Huang Yingzhuo Ma Haijie Cao Na Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期89-103,共15页
Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabrica... Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice. 展开更多
关键词 Superwetting Ag/α-Fe_(2)O_(3)heterostructure Enhanced photocatalytic and antibacterial activities Water purification Long-term reusability
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Polysulfide nanoparticles-reduced graphene oxide composite aerogel for efficient solar-driven water purification 被引量:2
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作者 Fantao Meng Yuang Zhang +2 位作者 Shufen Zhang Benzhi Ju Bingtao Tang 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期267-274,共8页
Along with the environmental pollution, the scarcity of clean water seriously threatens the sustainable development of human society.Recently, the rapid development of solar evaporators has injected new vitality into ... Along with the environmental pollution, the scarcity of clean water seriously threatens the sustainable development of human society.Recently, the rapid development of solar evaporators has injected new vitality into the field of water purification. However, the industry faces a considerable challenge of achieving comprehensive purification of ions, especially the efficient removal of mercury ions. In this work, we introduce an ideal mercury-removal platform based on facilely and cost-effectively synthesized polysulfide nanoparticles(PSNs). Further development of PSN-functionalized reduced graphene oxide(PSN-rGO) aerogel evaporator results in achieving a high evaporation rate of 1.55 kg m^(-2)h^(-1)with energy efficiency of 90.8% under 1 sun. With the merits of interconnected porous structure and adsorption ability, the photothermal aerogel presents overall purification of heavy metal ions from wastewater. During solar desalination, salt ions can be rejected with long-term stability. Compared with traditional water purification technologies, this highly efficient solar evaporator provides a new practical method to utilize clean energy for clean water production. 展开更多
关键词 Composite aerogel Solar vapor generation Photothermal conversion Water purification
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Liver replacement therapy with extracorporeal blood purification techniques current knowledge and future directions 被引量:3
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作者 Panagiotis Papamichalis Katerina G Oikonomou +11 位作者 Asimina Valsamaki Maria Xanthoudaki Periklis Katsiafylloudis Evangelia Papapostolou Apostolia-Lemonia Skoura Michail Papamichalis Marios Karvouniaris Antonios Koutras Eleni Vaitsi Smaragdi Sarchosi Antonios Papadogoulas Dimitrios Papadopoulos 《World Journal of Clinical Cases》 SCIE 2023年第17期3932-3948,共17页
Clinically,it is highly challenging to promote recovery in patients with acute liver failure(ALF)and acute-on-chronic liver failure(ACLF).Despite recent advances in understanding the underlying mechanisms of ALF and A... Clinically,it is highly challenging to promote recovery in patients with acute liver failure(ALF)and acute-on-chronic liver failure(ACLF).Despite recent advances in understanding the underlying mechanisms of ALF and ACLF,standard medical therapy remains the primary therapeutic approach.Liver transplantation(LT)is considered the last option,and in several cases,it is the only intervention that can be lifesaving.Unfortunately,this intervention is limited by organ donation shortage or exclusion criteria such that not all patients in need can receive a transplant.Another option is to restore impaired liver function with artificial extracorporeal blood purification systems.The first such systems were developed at the end of the 20th century,providing solutions as bridging therapy,either for liver recovery or LT.They enhance the elimination of metabolites and substances that accumulate due to compromised liver function.In addition,they aid in clearance of molecules released during acute liver decompensation,which can initiate an excessive inflammatory response in these patients causing hepatic encephalopathy,multiple-organ failure,and other complications of liver failure.As compared to renal replacement therapies,we have been unsuccessful in using artificial extracorporeal blood purification systems to completely replace liver function despite the outstanding technological evolution of these systems.Extracting middle to high-molecular-weight and hydrophobic/protein-bound molecules remains extremely challenging.The majority of the currently available systems include a combination of methods that cleanse different ranges and types of molecules and toxins.Furthermore,conventional methods such as plasma exchange are being re-evaluated,and novel adsorption filters are increasingly being used for liver indications.These strategies are very promising for the treatment of liver failure.Nevertheless,the best method,system,or device has not been developed yet,and its probability of getting developed in the near future is also low.Furthermore,little is known about the effects of liver support systems on the overall and transplant-free survival of these patients,and further investigation using randomized controlled trials and meta-analyses is needed.This review presents the most popular extracorporeal blood purification techniques for liver replacement therapy.It focuses on general principles of their function,and on evidence regarding their effectiveness in detoxification and in supporting patients with ALF and ACLF.In addition,we have outlined the basic advantages and disadvantages of each system. 展开更多
关键词 Liver failure TRANSPLANTATION Blood purification Liver replacement therapy Artificial extracorporeal systems Transplant-free survival
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Preparation of Silica Nanosphere with Vertical Pore and Its Application in Oil-water Separation
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作者 FAN Hui CAI Yun +3 位作者 BAI Ping YUAN Qinwen WANG Dong CHEN Yuanli 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期299-303,共5页
Uniform monodispersed mesoporous silica nanospheres with vertical pores were successfully synthesized using chiral amphiphilic small molecule L-16Ala5PyClO4and solvents as dual templates via solgel transcription.The m... Uniform monodispersed mesoporous silica nanospheres with vertical pores were successfully synthesized using chiral amphiphilic small molecule L-16Ala5PyClO4and solvents as dual templates via solgel transcription.The morphologies and pore sizes of silicas are adjustable by changing the type and amount of solvents in the reaction systems.With the increase of the organic solvent content,the morphologies of the obtained silica changed from nanospheres with vertical pore structures to nanosheets structures.When 1 mL of benzene,cyclohexane or toluene were used as solvents,only silica nanospheres were obtained,the BET surface areas of silica nanospheres reached 600.7,669.5,and 560.8 m^(2)/g,respectively.The pore sizes were 3.51,3.54,and 3.46 nm,respectively.Significantly,these ordered silica nanospheres/poly(vinyl alcohol-co-ethylene)(PVAco-PE)nanofiber membranes have high separation efficiencies(>99%)for n-hexane/water mixtures. 展开更多
关键词 sol-gel preparation MESOPOROUS silica nanosphere oil-water separation
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Purification of Moringa oleifera Leaves Protease by Three-Phase Partitioning and Investigation of Its Potential Antibacterial Activity
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作者 Adam Abdoulaye Agossou D. P. Noumavo +6 位作者 Durand Dah-Nouvlessounon Messan A. B. Ohin Hasan Bayraktar Farid T. Bade Honoré S. Bankole Lamine Baba-Moussa Farid Baba-Moussa 《American Journal of Plant Sciences》 CAS 2023年第1期64-76,共13页
One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for thei... One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for their purifications. As such, three-phase partitioning (TPP) was used to purify protease from moringa (Moringa oleifera). TPP is an emerging, promising, non-chromatographic and economical technology which is simple, quick, efficient and often one-step process for the separation and purification of bioactive molecules from natural sources. It involves the addition of salt (ammonium sulphate) to the crude extract followed by the addition of an organic solvent (butanol). The protein appears as an interfacial precipitate between upper organic solvent and lower aqueous phases. The various conditions such as ammonium sulphate, ratio of crude extract to t-butanol and pH which are required for attaining efficient purification of the protease fractions were optimized. Under optimized conditions, it was seen that, 35% of ammonium sulphate saturation with 1:0.75 ratio of crude extract to t-butanol at pH 7 gave 4.94-fold purification with 96.20% activity yield of protease in the middle phase of the TPP system. The purified enzyme from Moringa oleifera has no antimicrobial effect on the pathogenic bacteria tested. However, this purified enzyme, can be considered as a promising agent, cheap, and safe source which is suitable for using in various industries. 展开更多
关键词 Three-Phase Partitioning Moringa oleifera PROTEASE Protein purification ANTIMICROBIAL
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Wax deposition modeling in oil-water stratified pipe flow
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作者 Hui-Shu Liu Ji-Miao Duan +5 位作者 Jiang Li Jian Wang Hao Yan Ke-Yu Lin Ke-Cheng Gu Chang-Jun Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期526-539,共14页
Wax deposition in oil-water stratified flow is commonly encountered onshore and offshore oil production pipe systems,and typically reduces transportation capacity of oil.The accurate predicted model of wax deposition ... Wax deposition in oil-water stratified flow is commonly encountered onshore and offshore oil production pipe systems,and typically reduces transportation capacity of oil.The accurate predicted model of wax deposition has becomes an indispensable approach to design effective remediation strategies.However,a reliable mechanistic model for wax deposition prediction in oil-water two-phase stratified pipe flow is lacking to validate the deposition process.In this work,a three-dimensional(axial,radial,and angular)robust wax deposit model for oil-water stratified circular pipe flow was developed.The model of formation of a gel deposit based on the first principles of rheology was developed,associated with the results obtained from hydrodynamics and heat/mass transfer simulations.The predictions for wax deposition are found to compare satisfactorily with experimental data with two different oils for single phase and four different water cuts for oil-water stratified pipe flow.It can be seen from the wax gelation mechanism that an increase in water cut can help to reduce the wall/oil-deposit interface shear stress,thereby leading to an increase in the degree of gelation as well as the deposit rate.Furthermore,a local deposit analysis in the circumferential direction was conducted,for water cut 75%and total flow rate 5 m3/h,which provided insights to understand that the thickness on pipe wall was roughly uniformly distributed locates near the top of the pipe and the nearer the position gets close to two points,where the oil-water interface contacts the inner wall,the deposition thickness quickly dropped to 0.It was attributed to the fact that a roughly uniformly thickness far away from the oil-water interface contact the inner wall resulted in the slowly changes temperature along the circumferential pipe wall wetted by oil. 展开更多
关键词 Wax deposition oil-water flow Stratified flow Heat and mass transfer
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Experiments and model development of p-nitrochlorobenzene and naphthalene purification in a continuous tower melting crystallizer
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作者 Wenlong Xiao Yonglin Li +2 位作者 Zhengming Yi Sheng Yang He’an Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期9-17,共9页
With the increasing demand for high-purity products,the industrial application of melt crystallization technology has been highly concerned.In this study,the purification process of nitrochlorobenzene binary eutectic ... With the increasing demand for high-purity products,the industrial application of melt crystallization technology has been highly concerned.In this study,the purification process of nitrochlorobenzene binary eutectic system(NBES)and naphthalene–benzothiophene solid solution system(NBSSS)in tower melting crystallizer is analyzed,and a mathematical model of crystallization process is established.The key parameters in terms of feed concentration,crystal bed height,reflux ratio and stirring speed effi-ciency on purification effects were discussed by the established model.The results show that the concentration of p-nitrochlorobenzene was purified from 90.85%to 99.99%,when the crystal bed height is 600 mm,the reflux ratio is 2.5,and the stirring speed is 12 rmin^(-1).The naphthalene concentration is purified from 95.89%to 99.99%,when the crystal bed height is 400 mm,the reflux ratio is 1.43,and the stirring speed is 16 rmin^(-1).The quality of the model is evaluated by the ARD(average relative deviation).The minimum ARD values of the NBES and NBSSS are 2.39%and 5.22%,respectively,indicating the model satisfactorily explains the purification process. 展开更多
关键词 CRYSTALLIZATION Separation Mathematical modeling CRYSTALLIZER purification
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Solubility study and selective purification of HMX explosive in organic electrolyte solution of zinc acetate/diethylene glycol
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作者 Javad Ghorbani Sajjad Damiri Hamid Reza Pouretedal 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第11期15-23,共9页
In this study, an organic electrolyte solution based on zinc acetate/diethylene glycol(ZA/DEG) is introduced for the selective purification of cyclotetramethylene tetranitramine(HMX) high explosive from its identical ... In this study, an organic electrolyte solution based on zinc acetate/diethylene glycol(ZA/DEG) is introduced for the selective purification of cyclotetramethylene tetranitramine(HMX) high explosive from its identical homologue cyclotrimethylene trinitramine(RDX). The dielectric constant of various organic solutions were investigated through Electrochemical Impedance Spectroscopy(EIS) in the range of 1.0 Hz—30 MHz. and some quantum-chemical descriptors of RDX and HMX dissolutions in the ZA cosolvent were analyzed using Density Functional Theory(DFT). The results show dielectric constant and solubility of RDX is higher than that of HMX, and by increasing of ZA concentration in DEG solvent, the values of dielectric constants were enhanced. Furthermore, the presence of ZA cosolvent on the solubility of two explosives was statistically investigated by Central Composite Design(CCD) of experiment, and some solubility parameters including activity coefficient, dissolving enthalpy, and mixing enthalpies were determined. The experimental results indicate that the weight ratio of RDX to HMX solubility in the proposed organic electrolyte changes up to 30 times, which provides a selective and sequential separation method to separate two materials with similar chemical properties with a separation efficiency>98% and HMX purity> 99.8%. The X-Ray Diffraction(XRD) analysis, High-Performance Liquid Chromatography(HPLC), Laser-Induced Breakdown Spectroscopy(LIBS), and Fourier Transform Infrared Spectroscopy(FT-IR) approves the acceptable quality of the separated materials. The proposed method makes the efficient and safe purification of high-quality HMX for application in oil and gas well perforating gun charges, using a nonvolatile and inflammable organic electrolyte. 展开更多
关键词 Organic electrolyte purification SOLUBILITY HMX RDX Diethylene glycol
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Preparation of Hydrophobic Fly Ash by Surface Modification and Oil-water Separation Devices
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作者 于阳剑 刘鹏 +1 位作者 WANG Fazhou HU Chuanlin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期695-700,共6页
A simple and effective superhydrophobic mesh was designed and made to separate oil-water mixture. Alkali-activated fly ash reacted with 1-bromooctadecane to prepare superhydrophobic modified fly ash (MFA) with low sur... A simple and effective superhydrophobic mesh was designed and made to separate oil-water mixture. Alkali-activated fly ash reacted with 1-bromooctadecane to prepare superhydrophobic modified fly ash (MFA) with low surface energy through Williamson ether synthesis. The MFA powder was then coated uniformly on a stainless steel mesh (SSM) along with the epoxy resin E44 and curing agent T31 to give the superhydrophobic MFA-modified stainless steel mesh (MFA-SSM). The MFA-SSM has a high static water contact angle (CA) of 150.1°and can separate various oil or organic solvent from water with>95%separation efficiency. The oil-water separation efficiency remained high after 30 runs of petroleum ether/water separation.The developed superhydrophobic stainless steel mesh is expected to have wider use in oil-water separation. 展开更多
关键词 oil-water separation superhydrophobic stainless steel mesh Williamson ether synthesis
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Faithful and efficient hyperentanglement purification for spatial-polarization-time-bin photon system
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作者 杜芳芳 樊钢 +1 位作者 吴一鸣 任宝藏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期140-150,共11页
We present a faithful and efficient hyperentanglement purification protocol(hyper-EPP)for nonlocal two-photon systems in spatial-polarization-time-bin hyperentangled Bell states.As the single-photon detectors can dete... We present a faithful and efficient hyperentanglement purification protocol(hyper-EPP)for nonlocal two-photon systems in spatial-polarization-time-bin hyperentangled Bell states.As the single-photon detectors can detect and herald the undesirable properties caused by side leakage and finite coupling strength,the parity-check gates and swap gates of our hyper-EPP in the spatial,polarization and time-bin mode degrees of freedom(DoFs)work faithfully.The qubit-flip errors in photon systems in three DoFs can be corrected effectively with the faithful parity-check gates and the photon pairs can be reused to distill high-fidelity ones by introducing the faithful swap gates,which greatly increases the efficiency of our hyper-EPP.Further,the maximal hyperentanglement can be obtained in principle by operating multiple rounds of the hyper-EPP. 展开更多
关键词 quantum communication hyperentanglement purification photon system multiple degrees of freedom
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