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Exercise-induced irisin in bone and systemic irisin administration reveal new regulatory mechanisms of bone metabolism 被引量:27
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作者 Jin Zhang Paloma Valverde +9 位作者 Xiaofang Zhu Dana Murray Yuwei Wu Liming Yu Hua Jiang Michel M Dard Jin Huang Zhiwei Xu Qisheng Tu Jake Chen 《Bone Research》 SCIE CAS CSCD 2017年第1期49-62,共14页
Irisin is a polypeptide hormone derived from the proteolytic cleavage of fibronectin-type III domain- containing 5 (FNDC5) protein. Once released to circulation upon exercise or cold exposure, irisin stimulates brow... Irisin is a polypeptide hormone derived from the proteolytic cleavage of fibronectin-type III domain- containing 5 (FNDC5) protein. Once released to circulation upon exercise or cold exposure, irisin stimulates browning of white adipose tissue (WAT) and uncoupling protein I (UCP1) expression, leading to an increase in total body energy expenditure by augmented UCPl-mediated thermogenesis. It is currently unknown whether irisin is secreted by bone upon exercise or whether it regulates bone metabolism in vivo. In this study, we found that 2 weeks of voluntary wheel-running exercise induced high levels of FNDC5 messenger RNA as well as FNDC5/irisin protein expression in murine bone tissues. Increased immunoreactivity due to exercise-induced FNDC5/irisin expression was detected in different regions of exercised femoral bones, including growth plate, trabecular bone, cortical bone, articular cartilage, and bone-tendon interface. Exercise also increased expression of osteogenic markers in bone and that of UCP1 in WAT, and led to bodyweight loss. Irisin intraperitoneal (IP) administration resulted in increased trabecular and cortical bone thickness and osteoblasts numbers, and concurrently induced UCP1 expression in subcutaneous WAT. Lentiviral FNDC5 IP administration increased cortical bone thickness. In vitro studies in bone cells revealed irisin increases osteoblastogenesis and mineralization, and inhibits receptor activator of nuclear factor-kB ligand (RANKL)- induced osteoclastogenesis. Taken together, our findings show that voluntary exercise increases irisin production in bone, and that an increase in circulating irisin levels enhances osteogenesis in mice. 展开更多
关键词 Exercise-induced irisin in bone and systemic irisin administration reveal new regulatory mechanisms of bone metabolism BONE
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STUDY OF THE MECHANISMS FOR BIOLOGY WINDOW-EFFECTS OF ELECTROMAGNETIC WAVES ON BIOSYSTEMS
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《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第4期108-109,共2页
关键词 AJ study OF THE mechanismS FOR BIOLOGY WINDOW-EFFECTS OF ELECTROMAGNETIC WAVES ON BIOsystemS
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Mechanism study on UV-induced photodegradation of nonylphenol ethoxylates by intermediate products analysis 被引量:8
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作者 Ling Chen Hai Yun Zhou +1 位作者 Lan Liu Qin Ying Deng 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第4期473-475,共3页
Photodegradation of nonylphenol ethoxylates (NPloEO) was investigated in laboratory scale under UV irradiation. The intermediate photodegradation products were analyzed by LC-ESI-MS. Three kinds of intermediate prod... Photodegradation of nonylphenol ethoxylates (NPloEO) was investigated in laboratory scale under UV irradiation. The intermediate photodegradation products were analyzed by LC-ESI-MS. Three kinds of intermediate products including aldehydic compounds, carboxylic compounds and cyclohexanyl compounds were identified. Five main degradation routes involving the oxidation of the alkyl chain and ethoxylate unit, shortening of the alkyl chain and ethoxylate unit, hydrogenation of the benzene ring were proposed. 展开更多
关键词 PHOTODEGRADATION Nonylphenol ethoxylates Intermediate products mechanism study
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Chemiluminescence determination of 20 amino acids and the mechanism study 被引量:3
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作者 Yan Ming Liu Zhuan Li Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期856-859,共4页
It was found that 20 amino acids could inhibit the intensity of the luminol-H_2O_2-CuSO_4 chemiluminescence system.Using this character,a rapid and sensitive method for the determination of 20 amino acids was develope... It was found that 20 amino acids could inhibit the intensity of the luminol-H_2O_2-CuSO_4 chemiluminescence system.Using this character,a rapid and sensitive method for the determination of 20 amino acids was developed with flow injection coupled with chemiluminescence detection.Under the optimal conditions,the detection limits of 20 amino acids were in the range of 4.5×10^(-7)- 4.3×10^(-10) mol/L,and the relative standard deviations were less than 3.2%.The proposed method was successfully applied to drug analysis.The possible mechanism was also discussed. 展开更多
关键词 CHEMILUMINESCENCE Flow injection Amino acid mechanism study
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Parametric study of control mechanism of cortical bone remodeling under mechanical stimulus 被引量:1
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作者 YananWang Qing-Hua Qin 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期37-44,共8页
The control mechanism of mechanical bone remodeling at cellular level was investigated by means of an extensive parametric study on a theoretical model described in this paper. From a perspective of control mechanism,... The control mechanism of mechanical bone remodeling at cellular level was investigated by means of an extensive parametric study on a theoretical model described in this paper. From a perspective of control mechanism, it was found that there are several control mechanisms working simultaneously in bone remodeling which is a complex process. Typically, an extensive parametric study was carried out for investigating model parameter space related to cell differentiation and apoptosis which can describe the fundamental cell lineage behaviors. After analyzing all the combinations of 728 permutations in six model parameters, we have identified a small number of parameter combinations that can lead to physiologically realistic responses which are similar to theoretically idealized physiological responses. The results presented in the work enhanced our understanding on mechanical bone remodeling and the identified control mechanisms can help researchers to develop combined pharmacological-mechanical therapies to treat bone loss diseases such as osteoporosis. 展开更多
关键词 Control mechanism Parametric study Mechanical bone remodeling
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Clinical Observation on Treatment of 78 Patients of B-Thalassemla with Bushen Ylsul (补肾益髓) Method and Study on Its Molecular Mechanism 被引量:6
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作者 吴志奎 蔡辉国 +7 位作者 方素萍 张新华 王蕾 陈玉英 吕鑫霞 黄有文 王荣新 陈佩珍 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第2期141-141,共1页
Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with ... Objective: To study the treatment of B-Thalas-semia (ThE) with Chinese herbal medicine for Bushen Yisui (BSYS), its theoretical base and molecular mechanism. Methods: Seventy-eight patients with ThE were treated with BSYS recipe (consisted of 11 Chinese herbal drugs as Dogwood fruit, Fleeceflower root, prepared Rehmannia root and turtle shell, etc.) orally taken, 3 times per day, 10 g/time, 3 months as one therapeutic course. Hemoglobin (Hb), red blood cell (RBC), reticulocyte (Ret) and hemoglobin F (HbF) were checked every month. At the same time, PAGE, PVR, PCR-SSCP, RT-PCR, DNA series analysis, mRNA gene expression analysis techniques were used to conduct the systematic gene analysis in patients to study the molecular mechanism of TCM treatment from aspects of gene mutation, gene expression and control-regulation. Results: All the blood criteria in patients after BSYS treatment were improved significantly with clinical symptoms 展开更多
关键词 of in gene Method and study on Its Molecular mechanism Clinical Observation on Treatment of 78 Patients of B-Thalassemla with Bushen Ylsul HbF on with
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Okadaic acid: a tool to study regulatory mechanisms for neurodegeneration and regeneration in Alzheimer's disease 被引量:4
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作者 Pradip Kumar Kamat Chandishwar Nath 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第3期365-367,共3页
Okadaic acid: Okadaic acid (OKA), a polyether (C38 fatty acid) toxin, is a potent and selective inhibitor of protein phosphatase, PP1 and protein phosphatase 2A (PP2A). It is mainly extracted from a black spong... Okadaic acid: Okadaic acid (OKA), a polyether (C38 fatty acid) toxin, is a potent and selective inhibitor of protein phosphatase, PP1 and protein phosphatase 2A (PP2A). It is mainly extracted from a black sponge Hallichondria okadaii and has been suggested to play a potent probe for studying the various molecular, cellular, biochemical and mechanism of neurotoxicity. It is known as a selective and potent in- hibitor of serine/threonine phosphatases 1 and 2A induces hyperphosphorylation of tau in vitro and in vivo. It has been reported that Alzheimer's disease (AD) is a complex multi- factorial neurodegenerative disorder and hyperphosphor- ylated tau protein is a major pathological hallmark of AD. The reduced activity of phosphatases like, PP2A has been implicated in the brain of AD patients. OKA also induced inhibition of protein phosphatases cause neurofibrillary tangles (NFTs) like pathological changes and tau hyperphos- phorylation seen in AD pathology. Our and others reports inferred that OKA induces neurodegeneration along with tau hyperphosphorylation, GSK3β activation, oxidative stress, neuroinflammation and neurotoxicity which are char- acteristic of AD pathology (Figure 1). 展开更多
关键词 a tool to study regulatory mechanisms for neurodegeneration and regeneration in Alzheimer’s disease Okadaic acid AD
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A Numerical Study on the Mechanisms Producing Forces on Cylinders Interacting with Stratified Shear Environments 被引量:1
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作者 Yin Wang Lingling Wang +2 位作者 Yong Ji Zhicheng Xi Wenwen Zhang 《Fluid Dynamics & Materials Processing》 EI 2021年第2期471-485,共15页
A three dimensional(3D)numerical wave flume is used to investigate carefully the ISWs(Internal solitary wave)forces acting on cylinders interacting with a stratified shear environment.Using the Large-Eddy Simulation(L... A three dimensional(3D)numerical wave flume is used to investigate carefully the ISWs(Internal solitary wave)forces acting on cylinders interacting with a stratified shear environment.Using the Large-Eddy Simulation(LES)approach and analyzing the distribution of shear stress and pressure along the surface of the cylinder,the differential pressure resistance and the viscous force are obtained.The method of multiple linear regression analysis is adopted and a comprehensive influence coefficient is determined accordingly to account for the dimensionless forces acting on the cylinder.Results show that the differential pressure resistance on a square cylinder is 1.5 times higher than that on a circular cylinder in the upper layer,while the differential pressure resistance on a square cylinder is 3.5 times larger than that on a circular cylinder in the lower layer.The viscous force is 1–2 orders of magnitude smaller than the differential pressure resistance,which means that the viscous force could be ignored.The comprehensive influence coefficient shows positive correlation with the relative wave height and negative correlation with upper and lower water depth ratio. 展开更多
关键词 Internal solitary waves cylinders force behaviors mechanism study numerical simulation
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The study on the mechanism of Sodium aescinate combined with Xuesaitong for cerebral thrombosis treatment 被引量:2
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作者 Ming-Ling Deng 《Journal of Hainan Medical University》 2017年第2期161-165,共5页
Objective:To observe the mechanism of Sodium aescinate combined with Xuesaitong for cerebral thrombosis treatment and offer clinical help to cerebral thrombosis treatment. Methods:A total of 92 patients with cerebral ... Objective:To observe the mechanism of Sodium aescinate combined with Xuesaitong for cerebral thrombosis treatment and offer clinical help to cerebral thrombosis treatment. Methods:A total of 92 patients with cerebral thrombosis were selected and randomly divided into groups: the observation group (46 people) and the control group (46 people).The patient in the control group were treated with conventional therapy and the patients in the observation group were treated with Sodium aescinate combined with Xuesaitong on the basis of conventional therapy. Inflammatory factors (IL-6, IL-10, TNF-α and CRP), Nerve cell factor (NSE, NGF and NTF) and blood rheology indexes (Fg, BVH, BVL and PV) were detected and analyzed before and after treatment.Results:The comparison of inflammatory factors, Nerve cell factor and blood rheology indexes in the two groups before treatment were not statistically significant. Inflammatory factors (IL-6, TNF-α and CRP), Nerve cell factor (NSE) and blood rheology indexes (Fg, BVH, BVL and PV) in both groups after treatment significantly decreased compared with that before treatment. Inflammatory factors (IL-10), Nerve cell factor (GF and NTF) in both groups after treatment significantly increased compared with that before treatment. The changes were statistically significant. Inflammatory factors (IL-6, TNF-α and CRP), Nerve cell factor (NSE) and blood rheology indexes (Fg, BVH, BVL and PV) in observation group after treatment decreased more significantly than that in control group, and inflammatory factors (IL-10), Nerve cell factor (GF and NTF) increased more significantly than that in control group. The difference between two groups was considered statistically significant.Conclusion:Sodium aescinate combined with Xuesaitong could inhibit the inflammatory reaction, improve the blood flow condition and promote rehabilitation in patients with cerebral thrombosis. So it has a very important clinical significance of the treatment to cerebral hemorrhage. 展开更多
关键词 Sodium aescinate study on the mechanism Cerebral THROMBOSIS XUESAITONG COMBINED TREATMENT
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Theoretical Study on the Pyrolysis Mechanism and Kinetics of 3-Hydroxy-3-Methyl-2-Butanone
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作者 Wen Lin FENG Jie Hao CHEN Yan WANG (Department of chemistry, Beijing Normal University, Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期0-0,共2页
The mechanism and kinetics for the decomposition of 3-hydroxy-3-methyl-2-butanone have been studied by using the ab initio RHF/3-21G method. The calculated activation barrier of the reaction is 249.6kJ/mol which is in... The mechanism and kinetics for the decomposition of 3-hydroxy-3-methyl-2-butanone have been studied by using the ab initio RHF/3-21G method. The calculated activation barrier of the reaction is 249.6kJ/mol which is in reasonable agreement with the experimental data (222.2±3kJ/mol). The calculated results show that the decomposition is a concerted process with hydrogen transferring and bond breaking via a five-membered cyclic transition state. The thermal rate constants of the decomposition are obtained by calculating microcanonical probability fluxes through transition state1. 展开更多
关键词 KINETICS mechanism theoretical study rate constants
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Experimental Study on the Mechanism for the Formation of Sn- bearing Granite in Northern Guangxi
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作者 Liang Xiangji, Qiao Li, Wang Fusheng and Yang Chonghui Institute of Geology, Chinese Academy of Geological Sciences, Beijing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1994年第2期169-182,228,共15页
Experimental results have proved that the Xuefengian Sn-bearing biotite granites were formed by remelting and recrystallization of the Proterozoic metamorphic rocks of the Sibao Group at 500× 105-2000× 105 P... Experimental results have proved that the Xuefengian Sn-bearing biotite granites were formed by remelting and recrystallization of the Proterozoic metamorphic rocks of the Sibao Group at 500× 105-2000× 105 Pa and 750-570℃ and further testified that the F- and B-bear-ing aqueous solution played an important part in decreasing the formation temperature of the rocks. The results tally with the reality of the field geology. The authors have thus brought to light the mechanism for the formation of the Sn-bearing biotite granites and expounded the significance of their formation in the crust dynamics of South China. 展开更多
关键词 experimental study Sn-bearing biotite granites formation mechanism northern Guangxi
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Theoretical Study on the Reaction Mechanism between Dichlorocarbene and Armchair Single-walled Carbon Nanotubes
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作者 LI Rui-Fang SHANG Zhen-Feng XU Xiu-Fang WANG Gui-Chang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1120-1128,共9页
The reaction mechanism between CC12 and armchair single-walled carbon nanotubes (ASWCNTs) (3,3) and (4,4) has been studied by semiempirical AM1 and ab initio methods. The activation barriers of CC12 adding to AS... The reaction mechanism between CC12 and armchair single-walled carbon nanotubes (ASWCNTs) (3,3) and (4,4) has been studied by semiempirical AM1 and ab initio methods. The activation barriers of CC12 adding to ASWCNT (3,3) and (4,4) are computed and compared. The lower barrier of CC12 forms cycloaddition isomer on (3,3) maybe because the strain energy of (3,3) is larger than that of (4,4). Our theoretical results are consistent with the experimental results. 展开更多
关键词 armchair single-walled carbon nanotubes DICHLOROCARBENE reaction mechanism theoretical study
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Study on the Mechanism of Fluid Percussion Injuries on Immune Cells
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作者 Dasen Xu Nu Zhang Hui Yang 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期131-132,共2页
Background Traffic accidents,anti-terrorism,gas and chemical dangerous goods explosions,earthquake shock wave damage,and falling impacts in daily life and other events involving impact loads cause great harm to human ... Background Traffic accidents,anti-terrorism,gas and chemical dangerous goods explosions,earthquake shock wave damage,and falling impacts in daily life and other events involving impact loads cause great harm to human organs and tissues,and even life-threatening.Such injuries are called impact damage.Although during the previous wars,the treatment of impact injuries has been greatly improved,and its treatment has been widely used in clinical practice.However,under the current development of society,the impact damage incident has not only been limited to the battlefield.Extreme organizations,frequent industrial production accidents,aircraft trains and other accidents have extended the impact damage incidents into daily society,seriously jeopardizing the health of civilians.Therefore,in order to better treat the injured organs under the impact load,such as the reconstruction and recovery of organ tissues,it is necessary to establish a corresponding system of clinical treatment methods for impact damage.In vitro models of traumatic injury are helping elucidate the pathobiological mechanisms responsible for dysfunction and delayed cell functional variation after mechanical stimulation of the single waveform pressure.It is likely that injury outcome is related to the biomechanical parameters of the traumatic event such as amplitudes and durations.However,the influence of impulsive pressure on endothelial function has not yet been fully studied in vitro.In this study,we developed a pressure loading device that produced positive by modifying an in vitro fluid percussion model and examined the effects of the pressures on macrophages’basic functions.Methods To model variations in the biomechanical injury parameters and simplify the experiment,single-use syringe was chosen to be the cell container and a drop hammer driven fluid percussion injury system(FPI)was designed and built to generate a single waveform with adjustable peak pressure and durations.Mice macrophage cells(Raw 264.7)were subjected to three types of the single positive pressure(120 kPa,550 kPa and 1 100 kPa).Every 12 hours we detected its basic functions(including phagocytosis and proliferative capacity)during the following 48 hours,also the immediate cell death.Results This single waveform pressure loading device could produce positive pressure with amplitudes of 70~1 200 kPa.After the pressure loading,there is no significant differences between the control cells and experiment cells.However,it does have a notable effect on its basic functions.The results showed that its phagocytosis and proliferative capacity were getting increased with a peak value on36 h and suddenly decreasing on 48 h.Moreover,these 4 regular curves are in proportion to the pressure.And the experimental results also indicate that the cell impact platform can achieve a single impact loading on the cells.The impact mainly causes the functional changes of RAW264.7 cells instead of directly causing its death.The cell proliferation activity and phagocytosis function are enhanced to some extent.Conclusions Those results indicate that single waveform pressure have a main effect on cell’s biological functions,not on cell death.And these effects on functions did have a regular functional rela-tionship.To explore more regular curves and the mechanism,we need more experiments such as genomics technical. 展开更多
关键词 study on the mechanism FLUID PERCUSSION INJURIES IMMUNE Cells
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Study on the Protective Mechanism of Acupuncture Regulating ICAM-5 mRNA Expression in Rats with Ischemic Stroke
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作者 Yating Shen Ximei Xie +4 位作者 Xiu Bai Hua Bai Xiaofan Chang Yuanyuan Tang Qiuyu Li 《Journal of Behavioral and Brain Science》 2021年第12期313-321,共9页
<b>Objective:</b> The objective is to investigate whether acupuncture can protect brain by regulating the expression of ICAM-5 mRNA in brain tissue. <b>Methods:</b> Male SD rats were used to co... <b>Objective:</b> The objective is to investigate whether acupuncture can protect brain by regulating the expression of ICAM-5 mRNA in brain tissue. <b>Methods:</b> Male SD rats were used to construct a middle cerebral artery occlusion reperfusion injury (Middle cerebral artery occlusion, MCAO) model, and the rats were randomly divided into 4 groups, namely the normal group (group A) and the sham operation group (group B), MCAO group (group C), MCAO + acupuncture group (group D);real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the expression of ICAM-5 mRNA in the brain tissue of the ischemic area, and HE staining and TUNEL were used to detect the level of neuronal apoptosis to evaluate the therapeutic effect. <b>Results:</b> Acupuncture can improve neuronal morphology and reduce neuronal apoptosis in rats with ischemic stroke. RT-qPCR: compared with group A and group B, the expression level of ICAM-5 mRNA in the brain tissues of group C and group D decreased, while compared with group C, The expression of ICAM-5 mRNA in the brain tissue of group D was significantly up-regulated (P < 0.05). There was no statistical difference between group A and group B (P > 0.05). <b>Conclusion:</b> The effectiveness of acupuncture in the treatment of ischemic stroke may achieve neuroprotection by up-regulating the expression level of ICAM-5 mRNA. 展开更多
关键词 Ischemic Stroke ACUPUNCTURE ICAM-5 mRNA mechanism study
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Study on dynamics of shear waves - Ⅱ Triggering mechanism and amplitude decay
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作者 YuanYeli Zheng Quan’an First Institute of Oceanography, State Oceanic Administration, Qingdao, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第2期171-178,共8页
Starting from vorticity equation, the triggering mechanism and amplitude decay of shear waves in the ocean are discussed in this paper. The theoretical analysis indicates that by the action of stripped external force ... Starting from vorticity equation, the triggering mechanism and amplitude decay of shear waves in the ocean are discussed in this paper. The theoretical analysis indicates that by the action of stripped external force (for examples, the sudden setting of stripped wind, moving stripped wind, etc. ), shear waves can be triggered. This is qualitatively consistent with satellite observations. The amplitude decay process of shear waves by the action of side friction is also discussed in the paper. The theoretical model is quantitatively consistent with satellite observations. 展开更多
关键词 exp Pro Triggering mechanism and amplitude decay study on dynamics of shear waves
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DSC STUDY ON THE WATER-ABSORBING MECHANISM OF PLASMA POLYMERIZED N-VINYL-2-PYROROLIDONE
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作者 Ding Sheng YU R.E.MARCHANT 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期889-892,共4页
Water existing in water-absorbing plasma polymerized N-vinyl-2-pyrrolidone(PPNVP) include pure bulk water, freezable water and non-freezing, or bound, water. The C-N bond of N, N-disubstituted amides in PPNVP was cons... Water existing in water-absorbing plasma polymerized N-vinyl-2-pyrrolidone(PPNVP) include pure bulk water, freezable water and non-freezing, or bound, water. The C-N bond of N, N-disubstituted amides in PPNVP was considered as an active binding site for bound water. 展开更多
关键词 DSC study ON THE WATER-ABSORBING mechanism OF PLASMA POLYMERIZED N-VINYL-2-PYROROLIDONE 加加 ESCA NVP
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THE STUDY OF THE REACTION OF THE QUASI-AROMATIC COMPLEX [Ni(PnAO)-6H]^(?)WITH FORMALDEHYDE: KINETICS AND MECHANISM
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作者 Bin SONG Qi Yan ZHANG Yun Ti CHEN Department of Chemistry, Nankai University, Tianjin 300071 R.K.MERMANN Department of Chemistry, University of Missouri, Columbia 65211 USA Biotechnology research center, Zhongshan University, Guangzhou, 510275. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期401-402,共2页
The kinetics of the reaction of [Ni(PnAO)—6H]° with formaldehyde was studied in H_2O—CH_3OH solution under neutral condition and a complicated mechanism with three steps including competitive, consecutive and r... The kinetics of the reaction of [Ni(PnAO)—6H]° with formaldehyde was studied in H_2O—CH_3OH solution under neutral condition and a complicated mechanism with three steps including competitive, consecutive and reverse reactions was proposed. 展开更多
关键词 ACH KINETICS AND mechanism PnAO THE study OF THE REACTION OF THE QUASI-AROMATIC COMPLEX WITH FORMALDEHYDE Ni
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THE STUDY ON THE MASS TRANSFER MECHANISM OF EUROPIUM ION THROUGH LIQUID SURFACTANT MEMBRANES
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作者 姜长印 郁建涵 朱永(贝睿) 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 1985年第1期11-19,共9页
The transfer of trivalent europium ion in a liquid surfactant membrane system is investigated in order toclarify the characteristics of liquid membrane separation process and the availability of this technique forreco... The transfer of trivalent europium ion in a liquid surfactant membrane system is investigated in order toclarify the characteristics of liquid membrane separation process and the availability of this technique forrecovering trivalent lanthanides and actinides.A layered structure model for the emulsion globule is sug-gested.The equations describing the relationship among the effective membrane thickness,the time andother factors are derived and verified experimentally.Results show that under certain conditions the decreas-ing concentration of europium ion in the external phase is proportional to the square root of the time,the acidity of the internal phase and the carrier concentration in the membrane phase.The membrane phase consists of kerosene(solvent),Span-80(surfactant)and di-(2-ethylhexyl) phosphoricacid(HDEHP,carrier).The internal phase is dilute nitric acid and the external phase is aqueous solu-tion containing Eu(NO3)3.The mass transfer rate of europium in this system is high and the recovery ofeuropium may be more than 99%. 展开更多
关键词 FIGURE show Eu HAZ THE study ON THE MASS TRANSFER mechanism OF EUROPIUM ION THROUGH LIQUID SURFACTANT MEMBRANES
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Study on the Mechanism of the Rearrangement Reaction of 3-n-Butylphthalide by Deuterium-Labelling
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作者 Bai Ling XU Zong Ru GUO +1 位作者 Xiao Tian LIANG Guang Zhong YANG (Institute of Materia Medica, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第6期479-482,共4页
By the Grignard reaction of 1,1-di-deutero-1-bromobutane with phthalaldehydic acid 1',1'-di-deutero-3-n-butyl phthalide was obtained, which underwent a rearrangement reaction using AlCl3 as catalyst in CS2 to ... By the Grignard reaction of 1,1-di-deutero-1-bromobutane with phthalaldehydic acid 1',1'-di-deutero-3-n-butyl phthalide was obtained, which underwent a rearrangement reaction using AlCl3 as catalyst in CS2 to give 1-methyl-5-carboxy-3,4-di-deutero-tetrahydronaphthalene. The mechanism was proposed to be a series of consecutive 1,2- hydride transfers rather than a direct 1,4-hydride transfer. 展开更多
关键词 PPM CHD study on the mechanism of the Rearrangement Reaction of 3-n-Butylphthalide by Deuterium-Labelling
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An AM1 Study on the Mechanism of Uridine Phospborolysis
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《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第11期999-1002,共4页
We have cd quantum chemical method tO ho the transition states of uridinephosphorolysis reaction under the neutral condition. Comparing the activation energies ofdifferent reaction modes, we conclude that uridine p... We have cd quantum chemical method tO ho the transition states of uridinephosphorolysis reaction under the neutral condition. Comparing the activation energies ofdifferent reaction modes, we conclude that uridine phosphorolysis takes Place mainlyaccording tO a concerted mechanism. The computational are consistent with somecritical experimental factsss. 展开更多
关键词 AM An AM1 study on the mechanism of Uridine Phospborolysis
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