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Phosphorus accumulation by bacteria isolated from a continuous-flow two-sludge system 被引量:15
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作者 BAO Lin-lin LI Dong +4 位作者 LI Xiang-kun HUANG Rong-xin ZHANG Jie LV Yang XIA Guang-qing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第4期391-395,共5页
In this article, polyphosphate-accumulating organisms (PAOs) from a lab-scale continuous-flow two-sludge system was isolated and identified, the different phosphorus accumulation characteristics of the isolates unde... In this article, polyphosphate-accumulating organisms (PAOs) from a lab-scale continuous-flow two-sludge system was isolated and identified, the different phosphorus accumulation characteristics of the isolates under anoxic and aerobic conditions were investigated. Two kinds of PAOs were both found in the anoxic zones of the two-sludge system, one of them utilized only oxygen as electron aeceptor, and the other one utilized either nitrate or oxygen as electron aeceptor. Of the total eight isolates, five isolates were capable of utilizing both nitrate and oxygen as electron acceptors to uptake phosphorus to some extent. And three of the five isolates showed good phosphorus accumulative capacities both under anoxic or aerobic conditions, two identified as Alcaligenes and one identified as Pseudomonas. Streptococcus was observed weak anoxic phosphorus accumulation because of its weak denitrification capacity, but it showed good phosphorus accumulation capacity under aerobic conditions. One isolates identified as Enterobacteriaceae was proved to be a special species of PAOs, which could only uptake small amounts of phosphorus under anoxic conditions, although its denitrification capacity and aerobic phosphorus accumulation capacity were excellent. 展开更多
关键词 aerobic phosphorus accumulation anoxic phosphorus accumulation continuous-flow two-sludge system polyphosphateaccumulating organisms (PAOs)
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Gastrointestinal bleeding in a patient with a continuous-flow biventricular assist device
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作者 Raymond V Mirasol Jason J Tholany +4 位作者 Hasini Reddy Billie S Fyfe-Kirschner Christina L Cheng Issam F Moubarak John L Nosher 《World Journal of Radiology》 CAS 2016年第4期428-433,共6页
The association between continuous-flow left ventricular assist devices(CF-LVADs)and gastrointestinal(GI)bleeding from angiodysplasia is well recognized.However,the association between continuous-flow biventricular as... The association between continuous-flow left ventricular assist devices(CF-LVADs)and gastrointestinal(GI)bleeding from angiodysplasia is well recognized.However,the association between continuous-flow biventricular assist devices(CF-BIVADs)and bleeding angiodysplasia is less understood.We report a case of GI bleeding from a patient with a CF-BIVAD.The location of GI bleeding was identified by nuclear red blood cell bleeding scan.The vascular malformation leading to the bleed was identified and localized on angiography and then by pathology.The intensity of bleeding,reflected by number of units of packed red blood cells needed for normalization of hemoglobin,as well as the time to onset of bleeding after transplantation,are similar to that seen in the literature for CF-LVADs and pulsatile BIVADs.While angiography only detected a dilated late draining vein,pathology demonstrated the presence of both arterial and venous dilation in the submucosa,vascular abnormalities characteristic of a late arteriovenous malformation. 展开更多
关键词 continuous-flow VENTRICULAR assist devices ANGIODYSPLASIA GASTROINTESTINAL BLEEDING ANGIOGRAPHY Heart failure
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Electrochemical Dearomative Spirocyclization of N-Acyl Sulfonamides in a Continuous-Flow Cell
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作者 Ting Liu Zhaojiang Shi +2 位作者 Yaofeng Yuan Yuqi Lin Ke-Yin Ye 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第9期980-984,共5页
The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and agrochemicals.Herein,we disclose an electrochemical d... The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and agrochemicals.Herein,we disclose an electrochemical dearomative spirocyclization of N-acyl sulfonamides in a continuous-flow cell.The reaction is simple and efficient without external catalysts or supporting electrolytes and could be applied in a decagram-scale synthesis. 展开更多
关键词 Electrochemistry continuous-flow DEAROMATIZATION SPIROCYCLIZATION SULFONAMIDES CYCLIZATION Methodology and reactions
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Continuous-flow enzymatic synthesis of chiral lactones in a three-dimensional microfluidic reactor
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作者 Xuelei Deng Meng Fan +7 位作者 Miao Wu Xiaoyan Zhang Ya Cheng Jianye Xia Yingping Zhuang Weiping Zhu Xuhong Qian Yunpeng Bai 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期299-303,共5页
A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic rea... A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic reactor.The microchannels(175 mm in length,0.9 mm in depth,and 1.72 mL in volume)were carved precisely inside a single borosilicate glass(90 mm×75 mm×12 mm)with ultrafast femtosecond laser micromachining.The flow field analysis and reaction simulation showed that the mixing of substrates and enzymes was enhanced,allowing the adjustment of residence time in a wide window.SmCR_(V4),a carbonyl reductase with excellent catalytic activity and enantioselectivity towardγ/δ-keto acids,was employed for the asymmetric synthesis of various chiral lactones.30 mmol/L(R)-γ-decalactone(3g)can be obtained in 26 s with a space-time yield(STY)up to 16,877 g L^(-1)d^(-1),which is 14.4 times higher than the highest STY of batch reaction reported previously.This continuous-flow process was applied to the synthesis of 6 chiral lactones.In addition,the scaled-up synthesis of 3g was carried out in 6 cascade microreactors continuously for 6 h,demonstrating the feasibility and stability of the 3D continuous-flow process in enzymatic synthesis of optically pure compounds. 展开更多
关键词 continuous-flow Flow chemistry MICROREACTOR BIOCATALYSIS Carbonyl reductase Asymmetric reduction
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Continuous-flow synthesis of polysubstituted γ-butyrolactones via enzymatic cascade catalysis
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作者 Liliang Chu Xiaoyan Zhang +6 位作者 Jianing Li Xuelei Deng Miao Wu Ya Cheng Weiping Zhu Xuhong Qian Yunpeng Bai 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期404-408,共5页
Polysubstituted chiral γ-butyrolactones are the core structural units of many natural products and high value-added flavors and fragrances used in the food and cosmetic industry. Current enzymatic cascade synthesis o... Polysubstituted chiral γ-butyrolactones are the core structural units of many natural products and high value-added flavors and fragrances used in the food and cosmetic industry. Current enzymatic cascade synthesis of these molecules faces the problems of low enzyme activity and phase separation in batch reaction, resulting in low productivity. Herein, we report a new continuous-flow process to synthesize the optically pure Nicotiana tabacum lactone(3S,4S)-4a and whisky lactone(3R,4S)-4b from α,β-unsaturatedγ-ketoesters. A new ene reductase(ER) from Swingsia samuiensi(Ss ER) and a carbonyl reductase(Ss CR)were engineered by directed evolution to improve their activity and thermostability. The continuous-flow preparative reactions were performed in two 3D microfluidic reactors, generating(3S,4S)-4a(99% ee and87% de) and(3R,4S)-4b(99% ee and 98% de) with space-time yields 3 and 7.4 times higher than those of the batch reactions. The significant enhancement in the productivity of enzyme cascade catalysis brought by cutting-edge continuous microfluidic technology will benefit the general multi-enzyme catalytic systems in the future. 展开更多
关键词 Enzyme catalysis Cascade catalysis Directed evolution continuous-flow γ-Butyrolactones
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八步连续流全合成维生素B_(1)工艺研究
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作者 Meifen Jiang Minjie Liu +2 位作者 Weijian Li Yingqi Xia Fen-Er Chen 《Engineering》 SCIE EI CAS CSCD 2024年第1期226-232,共7页
Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports... Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports on an integrated eight-step continuous-flow synthesis of vitamin B_(1) from commercially available 2-cyanoacetamide.The proposed continuous-flow process is based on advances in chemistry,engineering,and equipment design,and affords improved performance and safety compared with batch-mode manufacturing.Several challenges were precisely investigated and controlled,including mixing,unexpected clogging,solvent switches,an exothermic reaction,and the prevention of side reactions,using various micro-channel flow reactors,mixers,separators,and continuous filters.Vitamin B_(1) was produced with a separated yield of 47.7% and high purity,with a total residence time of about 3.5 h.This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry.Hence,the application of flow technology is of paramount importance for improving security,reducing waste,and,in particular,improving the efficiency of batch operations that require several days for manufacturing. 展开更多
关键词 Vitamin B_(1) continuous-flow synthesis MICRO-REACTOR Continuous manufacturing
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Analysis of floc morphology in a continuous-flow flocculation and sedimentation reactor 被引量:3
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作者 Pengfei Ren Jun Nan +1 位作者 Xinran Zhang Kai Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第2期268-275,共8页
The floc morphology was investigated in a continuous-flow reactor, in order to understand the evolution of flocs in practical flocculation and sedimentation processes in water utilities. Kaolin-humic acid suspension w... The floc morphology was investigated in a continuous-flow reactor, in order to understand the evolution of flocs in practical flocculation and sedimentation processes in water utilities. Kaolin-humic acid suspension was used as the test water, and polyaluminum chloride was chosen as the coagulant. An in-situ recognition system was applied to analyze the floc size, boundary fractal dimension, and eccentricity ratios. Particle numbers and turbidity were also determined in the sedimentation stage. At a coagulant dose of 1 mg/L as Al, the average floc size increased from 62 to 78 μm and the boundary fractal dimension was around 1.14, suggesting that flocs were compact and continuously grew during the entire flocculation process. However, with the dose increased to 5 mg/L, the average floc size decreased and stabilized at around 65 μm, with the fractal dimension of 1.20. It can be concluded that the excess coagulant doses resulted in the formation of chain-shaped, lower density, and more branched structure flocs, thereby restricting flocs’ further growth in the subsequent flocculation. Floc morphology analysis suggested that charge neutralization dominated in the initial flocculation stage, then the bridge and sweep mechanisms were dominant in the subsequent flocculation. In addition, compared with the traditional inclined plate settler, a novel V-shaped plate settler introduced in this study had an advantage in small size floc(less than 5 μm) removal. The V-shaped region could promote aggregate restructuring and re-flocculation; therefore, the V-shaped plate settler provides an alternative method for sedimentation. 展开更多
关键词 FLOCCULATION SEDIMENTATION continuous-flow reactor In-situ recognition system V-shaped plate settler tank
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Continuous-flow photochemistry: An expanding horizon of sustainable technology 被引量:3
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作者 Jingli Xie Dongyuan Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第9期2395-2400,共6页
Understanding the unique characteristics of continuous-flow photochemistry will lead to a paradigm shift in the way we enhance sustainability and wellbeing.In this mini-review,we first provide a succinct overview of w... Understanding the unique characteristics of continuous-flow photochemistry will lead to a paradigm shift in the way we enhance sustainability and wellbeing.In this mini-review,we first provide a succinct overview of working principles of this technique and discuss several recent synthetic protocols.Then,emphasis is given to those representative examples which address environmental issues such as indoor air pollutants and water contamination.Finally,recent progress made using this technique to deal with rising CO2 emission,solar energy utilization and biomedical equipment is described.It is believed that this mini-review could inspire more chemists to utilize this technique in their research,either in the academic or industrial field. 展开更多
关键词 continuous-flow photochemistry Synthesis Environmental application Micro-reaction technology Sustainable technology
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Egg-like magnetically immobilized nanospheres: A long- lived catalyst model for the hydrogen transfer reaction in a continuous-flow reactor 被引量:2
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作者 Yongjian Ai Zenan Hu +5 位作者 Zixing Shao Li Qi Lei Liu Junjie Zhou Hongbin Sun Qionglin Liang 《Nano Research》 SCIE EI CAS CSCD 2018年第1期287-299,共13页
A novel egg-like nanosphere was designed as a long-lived catalyst and is described as F%O4@nSiO2-NHa-Fe2O3.xBi2O3@mSiO2. The catalyst was prepared using a modified Stober method with template-free surface-protected et... A novel egg-like nanosphere was designed as a long-lived catalyst and is described as F%O4@nSiO2-NHa-Fe2O3.xBi2O3@mSiO2. The catalyst was prepared using a modified Stober method with template-free surface-protected etching. The catalyst particle consists of a magnetic Fe3O4 core as the "yolk", an inner silica shell bearing active Fe2O3"xBi2O3 species as the "egg white", and outer mesoporous silica as the "egg shell". It exhibits an excellent performance in the catalytic reduction of nitro aromatics to corresponding anilines in a fixed-bed continuous-flow reactor. The reaction could be performed at 80 ~C and could reach complete conversion in less than I rain with only a 7% excess of hydrazine hydrate. The catalyst bed could be easily shifted between different substrates without cross-contamination because of the uniformity of the catalyst particles. This catalyst exhibited very good stability in the continuous-flow protocol. In the long-term reduction of p-nitrophenol with 0.5 mmol.min-1 productivity, it worked for more than 1,500 cycles without any catalytic activity loss. 展开更多
关键词 magnetically immobilized continuous-flow egg-like catalytic reduction nitro compounds
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Estimation of photolysis half-lives of dyes in a continuous-flow system with the aid of quantitative structure-property relationship 被引量:1
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作者 Davoud BEIKNEJAD Mohammad Javad CHAICHI 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2014年第5期683-692,共10页
In this paper the photolysis half-lives of the model dyes in water solutions and under ultraviolet (UV) radiation were determined by using a continuous-flow spectrophotometric method. A quantitative structure- prope... In this paper the photolysis half-lives of the model dyes in water solutions and under ultraviolet (UV) radiation were determined by using a continuous-flow spectrophotometric method. A quantitative structure- property relationship (QSPR) study was carried out using 21 descriptors based on different chemometric tools including stepwise multiple linear regression (MLR) and partial least squares (PLS) for the prediction of the photolysis half-life (t1/2) of dyes. For the selection of test set compounds, a K-means clustering technique was used to classify the entire data set, so that all clusters were properly represented in both training and test sets. The QSPR results obtained with these models show that in MLR-derived model, photolysis half-lives of dyes depended strongly on energy of the highest occupied molecular orbital (EHoMO), largest electron density of an atom in the molecule (ED^+) and lipophilicity (logP). While in the model derived from PLS, besides aforementioned EHOMO and ED^+ descriptors, the molecular surface area (Sm), molecular weight (M-W), electronegativity (X), energy of the second highest occupied molecular orbital (EHoMO- 1) and dipole moment (μ) had dominant effects on logt1/2 values of dyes. These were applicable for all classes of studied dyes (including monoazo, disazo, oxazine, sulfo- nephthaleins and derivatives of fluorescein). The results were also assessed for their consistency with findings from other similar studies. 展开更多
关键词 dye photolysis half-life quantitative structure-property relationship continuous-flow stepwise multiple linear regression partial least squares
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Continuous-flow synthesis of nitriles from aldehydes via Schmidt reaction
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作者 Wei Zhan Meng Tong +4 位作者 Ling Ji Han Zhang Zemei Ge Xin Wang Runtao Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第5期973-976,共4页
A continuous-flow synthesis of nitriles by Schmidt reaction has been developed.Using this procedure,a variety of aldehydes could be smoothly transformed into the desired nitriles in good to excellent yields.The mild r... A continuous-flow synthesis of nitriles by Schmidt reaction has been developed.Using this procedure,a variety of aldehydes could be smoothly transformed into the desired nitriles in good to excellent yields.The mild reaction conditions and the flowing reaction system greatly improved the safety and make the reaction easy to scale up. 展开更多
关键词 continuous-flow REACTION ALDEHYDES SCHMIDT REACTION NITRILES SAFETY
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Conformally anchoring nanocatalyst onto quartz fibers enables versatile microreactor platforms for continuous-flow catalysis
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作者 Jiahui Fan Jian Lu +3 位作者 Zhou Sha Weiwei Zuo Xiang Fei Meifang Zhu 《Science China Chemistry》 SCIE EI CSCD 2021年第9期1596-1604,共9页
Continuous-flow microreactors offer increased reactivity and reusability via unique reaction pathways to address a wide range of practical nanocatalysis problems.However,only limited platforms exist to employ these mi... Continuous-flow microreactors offer increased reactivity and reusability via unique reaction pathways to address a wide range of practical nanocatalysis problems.However,only limited platforms exist to employ these microreactors for versatile nanocatalytic reactions.In this work,we conformally anchored nickel oxide(Ni O)nanosheets onto quartz fibers(QFs),which exhibited a high catalytic activity using the hydrogenation of 4-nitrophenol(4-NP)as a model reaction in a batch reaction study.More importantly,we demonstrated that fiber-based QF@Ni O composites(e.g.,cotton,fabric,belt,felt)can be integrated as versatile platforms to develop microreactors for continuous-flow catalytic applications including hydrogenation reactions and dyecatalyzed degradation.This fiber-based three-dimensional(3 D)nanocatalyst architecture effectively drives continuous-flow catalytic reactions with unprecedented efficiency due to the easy diffusion of reactant molecules into the fibrous structure,allowing contact with catalytic active sites.Our approach to continuous-flow microreactor design uses surface hybridization as a guideline to immobilize nanocatalysts onto the QFs.These QF-based platforms,coupled with rational design,are expected to be applied to a wide range of nanocatalytic reactions. 展开更多
关键词 quartz fiber platform nanocatalyst immobilization MICROREACTOR continuous-flow catalysis
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Continuous-flow,one-pot synthesis of asymmetrical aromatic ureas from acids and amines via curtius rearrangement
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作者 Meng Tong Wei Zhan +3 位作者 Chengcheng Niu Zemei Ge Runtao Li Xin Wang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2022年第12期938-945,共8页
In the present study,we described a continuous-flow,one-pot synthesis of asymmetrical ureas using nucleophilic addition reaction of amines to isocyanates derived from acids’Curtius rearrangement.The advantages of thi... In the present study,we described a continuous-flow,one-pot synthesis of asymmetrical ureas using nucleophilic addition reaction of amines to isocyanates derived from acids’Curtius rearrangement.The advantages of this method included broad substrate scope,high yields,rapid reaction,simplicity,extraordinary safety,and easy scale-up. 展开更多
关键词 continuous-flow reaction Asymmetrical urea Curtius reaction Safety
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Intercross real-time control strategy in alternating activated sludge process for short-cut biological nitrogen removal treating domestic wastewater 被引量:4
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作者 AKIO TAKIGAWA 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期957-963,共7页
To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,per... To develop technically feasible and economically favorable dynamic process control(DPC)strategies for an alternating activated sludge(AAS)system,a bench-scale continuous-flow alternating aerobic and anoxic reactor,performing short-cut nitrogen removal from real domestic wastewater was operated under different control strategies for more than five months.A fixed-time control(FTC) study showed that bending-points on pH and oxidation-reduction potential(ORP)profiles accurately coincided with the major biologic... 展开更多
关键词 alternating activated sludge process continuous-flow real-time control NITRIFICATION
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Determination of Heroin Based on Analyte Pulse Perturbation to an Oscillating Chemical Reaction 被引量:4
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作者 RENJie GAOJin-zhang +5 位作者 Suo-nan ZHAOGuo-hu YANGWu LüDong-yu SUNKan-jun LIChong-yang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期534-538,共5页
A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodiu... A new analytical method is proposed for the determination of heroin based on a sequential perturbation caused by trace amounts of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium with the aid of a continuous-flow stirred tank reactor(CSTR). The method relies on the linear relationship between the change in oscillation period of the system and the concentration of heroin, with a detecting limit of 4.0×10^(-7) mol/L. The calibration curve fits a linear equation very well when the concentration of heroin is in the range of 2.0×10^(-6)_1.2×10^(-5) mol/L(r=0.9971). This method features good precision(RSD=0.98%). The influences of temperature, injection point, flow rate and reaction variables on the oscillation period were investigated in detail and a possible mechanism of the performance of heroin in the Cu(Ⅱ)-catalyzed oscillating reaction system is also discussed. The proposed method opens a new avenue for the determination of heroin. 展开更多
关键词 Cu(Ⅱ)-catalyzed oscillating reaction HEROIN Analyte pulse perturbation technique(APP) Mechanism continuous-flow stirred tank reactor(CSTR).
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Optimization of a continuous ultrasound assisted oxidative desulfurization(UAOD) process of diesel using response surface methodology(RSM) considering operating cost 被引量:2
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作者 Mohammad Dana Mohammad Amin Sobati +1 位作者 Shahrokh Shahhosseini Aminreza Ansari 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第5期1384-1396,共13页
A continuous-flow ultrasound-assisted oxidative desulfurization(UAOD)of partially hydro-treated diesel has been investigated using hydrogen peroxide-formic acid as simple and easy to apply oxidation system.The effects... A continuous-flow ultrasound-assisted oxidative desulfurization(UAOD)of partially hydro-treated diesel has been investigated using hydrogen peroxide-formic acid as simple and easy to apply oxidation system.The effects of different operating parameters of oxidation stage including residence time(2–24 min),formic acid to sulfur molar ratio(10–150),and oxidant to sulfur molar ratio(5–35)on the sulfur removal have been studied using response surface methodology(RSM)based on Box–Behnken design.Considering the operating costs of the continuous-flow oxidation stage including chemical and electrical energy consumption,the appropriate values of operating parameters were selected as follows:residence time of 16 min,the formic acid to sulfur molar ratio of 54.47,and the oxidant to sulfur molar ratio of 8.24.In these conditions,the sulfur removal and the volume ratio of the hydrocarbon phase to the aqueous phase were 86.90%and 4.34,respectively.By drastic reduction in the chemical consumption in the oxidation stage,the volume ratio of the hydrocarbon phase to the aqueous phase was increased up to 10.Therefore,the formic acid to sulfur molar ratio and the oxidant to sulfur molar ratio were obtained 23.64 and 3.58,respectively,which lead to sulfur removal of 84.38%with considerable improvements on the operating cost of oxidation stage in comparison with the previous works. 展开更多
关键词 Ultrasound-Assisted Oxidative Desulfurization(UAOD) continuous-flow system Sulfur removal Response Surface Methodology(RSM) Operating cost
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Continuous Flow Left Ventricular Assist Device Therapy:A Focused Review on Optimal Patient Selection and Long-Term Follow-up Using Echocardiography
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作者 Juan R.Vilaro Anita Szady +2 位作者 Mustafa M.Ahmed Jacqueline Dawson Juan M.Aranda 《Cardiovascular Innovations and Applications》 2015年第B10期107-118,共12页
Despite widespread awareness and use of scientifi cally proven life-prolonging medical and device-based therapies over the last two decades,heart failure remains a leading cause of morbidity,mortality,and health care ... Despite widespread awareness and use of scientifi cally proven life-prolonging medical and device-based therapies over the last two decades,heart failure remains a leading cause of morbidity,mortality,and health care expenditure in the United States.Mechanical circulatory support with a continuous-fl ow left ventricular assist device(CF-LVAD),either as a bridge to heart transplantation or as destination therapy,is an increasingly used treatment modality for patients with advanced heart failure syndromes that worsen despite their receiving standard therapies.CF-LVAD support creates unique hemodynamic alterations that must be understood to provide appropriate care for these patients before and after implantation.Echocardiography is essential in the evaluation of patients who are being considered for or are mechanically supported by CF-LVADs.Here we provide a focused clinical review on the use of echocardiography in two main aspects of the evaluation of these patients:(a)optimal patient selection for CF-LVAD support and(b)followup assessment of optimal pump function. 展开更多
关键词 ECHOCARDIOGRAPHY continuous-flow LEFT VENTRICULAR assist device heart failure decision making OUTCOMES
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2D reduced graphene oxide-titania nanocomposites synthesized under different hydrothermal conditions for treatment of hazardous organic pollutants
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作者 Migyeong Kim Won-Hwa Hong +2 位作者 Woong Kim Sung Hyuk Park Wan-Kuen Jo 《Particuology》 SCIE EI CAS CSCD 2018年第1期165-173,共9页
Two-dimensional reduced graphene oxide-titania (RGO-TiO2) composites were prepared using a single- step hydrothermal method under various hydrothermal reaction conditions. The morphological and surface characteristi... Two-dimensional reduced graphene oxide-titania (RGO-TiO2) composites were prepared using a single- step hydrothermal method under various hydrothermal reaction conditions. The morphological and surface characteristics of the RGO-TiO2 composites and reference materials were determined. The RGO-TiO2 composites showed photocatalytic activity for the decomposition of two target pollutants that was superior to both pure TiO2 and RGO under fluorescent daylight lamp illumination. The photo- catalytic activity of the RGO-TiO2 composite increased as the hydrothermal treatment time increased from 1 to 24 h, but then it decreased as the time increased to 36 h, which indicated the presence of an optimal treatment time. RGO-TiO2 composites activated by violet light-emitting diodes (LEDs) displayed lower decomposition efficiency than those activated by a daylight lamp, likely because of the lower light intensity of violet LEDs (0.2 mW/cm2) when compared with that of the daylight lamp (1.4mW/cm2). However, the photocatalytic decomposition of the target pollutants using the RGO-TiO2 composite was more energy-efficient using the violet LEDs. The photocatalytic reaction rates increased as the residence time decreased, whereas the reverse was true for the decomposition efficiency. 展开更多
关键词 TiO2 composite continuous-flow mode Hydrothermal time VioletLight emitting diode
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