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Complexity responses of Rhododendron species to climate change in China reveal their urgent need for protection
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作者 Kun-Ji Li xiao-fei liu +3 位作者 Jin-Hong Zhang Xiong-Li Zhou liu Yang Shi-Kang Shen 《Forest Ecosystems》 SCIE CSCD 2023年第4期425-435,共11页
Global climate change has been widely recognized as important factors that threaten biodiversity.Rhododendron species are not only famous woody ornamental plants worldwide but are also indispensable components in alpi... Global climate change has been widely recognized as important factors that threaten biodiversity.Rhododendron species are not only famous woody ornamental plants worldwide but are also indispensable components in alpine and subalpine vegetation in southwest China.However,the geographical distribution ranges response of this broad taxonomic group to future climate change remains not be fully understood.Herein,we studied the impact of climate change on the distribution of Rhododendron species in China by predicting the changes in their suitable habitats,centroid,and species richness under three climate change scenarios(SSP1-2.6,SSP2-4.5 and SSP5-8.5)in the 2090s.The species richness changes of Rhododendrons along altitude were also evaluated.In addition,we calculated the phylogenetic signals of distribution response to climate change.We found that the distribution responses of Rhododendron to climate change have weak phylogenetic signals.In the 2090s,the suitable habitats of about 87%of Rhododendron species will be reduced,77%of Rhododendron species are manifested as northward migration.The high species richness of Rhododendrons tends to migrate to transboundary areas with high altitudes in China.Some Rhododendron species with no concern previously should be taken seriously for their high risk of habitat loss under climate change.Thus,the urgent protection of Rhododendron species under climate change need to be paid more attention than previous acknowledged.We recommend carrying out the reintroduction of endangered species in future suitable habitat,strengthening the protection of transboundary areas with high species richness,and focusing on species with few concerns previously. 展开更多
关键词 RESCUE Woody plant Alpine ecosystem MOUNTAINTOP Diversity
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Raf/MEK/ERK Signaling Pathway Is Involved in the Inhibition of Glioma Cell Proliferation and Invasion in the Ketogenic Microenvironment
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作者 Wen-tao FAN xiao-fei liu liu Ri-chu LIANG 《Current Medical Science》 SCIE CAS 2023年第4期759-767,共9页
Objective:A high-fat,low-carbohydrate ketogenic diet has been used to treat malignant glioma,in which the Raf/MEK/ERK signaling pathway is overactivated.However,whether the Raf/MEK/ERK signaling pathway is involved in... Objective:A high-fat,low-carbohydrate ketogenic diet has been used to treat malignant glioma,in which the Raf/MEK/ERK signaling pathway is overactivated.However,whether the Raf/MEK/ERK signaling pathway is involved in the therapeutic effect of ketone bodies remains unknown.In this study,we investigated the effects of a major ketone body,3-hydroxybutyric acid(3-HBA),on the proliferation and metastasis of malignant glioblastoma cells and the underlying mechanism.Methods:Two human malignant glioblastoma cell lines(U87 and U251)were treated with different concentrations of 3-HBA with or without the Raf inhibitor PAF C-16 for 24 h.Cell proliferation,cell cycle,cell invasion,and phospholipase D1(PLD1)activity were determined.Protein and gene expression levels of Raf/MEK/ERK signaling pathway members were examined.Results:3-HBA significantly decreased cell proliferation,invasion,and intracellular PLD1 activity in both U87 and U251 glioblastoma cell lines.3-HBA treatment significantly increased the proportion of cells in the G1 phase and decreased the proportion of cells in S phase in U87 cells.In the U251 line,the proportion of treated cells in S phase was increased and proportion of cells in G2 was decreased.3-HBA treatment also significantly decreased the protein expression levels of Raf,MEK,p-MEK,ERK,p-ERK,and PLD1 while increasing p53 expression;an effect that was similar to treatment with the Raf inhibitor.Co-treatment of 3-HBA with the Raf inhibitor further enhanced the effects of the 3-HBA in both cell lines.Conclusion:We confirmed that a ketogenic microenvironment can inhibit glioma cell proliferation and invasion by downregulating the expression of PLD1 through the Raf/MEK/ERK signaling pathway. 展开更多
关键词 GLIOMA ketogenic microenvironment Raf/MEK/ERK
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Exploring the pathogenesis of idiopathic granulomatous mastitis based on the prolactin theory
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作者 Yan Zhang Wen-Di liu +2 位作者 Yan-Jun Chen Han liu xiao-fei liu 《Medical Theory and Hypothesis》 2023年第1期5-9,共5页
Prolactin(PRL),as a cytokine,plays a variety of multidirectional roles in immunity and inflammation.An autoimmune condition known as idiopathic granulomatous mastitis(IGM)involves many inflammatory cells and cytokines... Prolactin(PRL),as a cytokine,plays a variety of multidirectional roles in immunity and inflammation.An autoimmune condition known as idiopathic granulomatous mastitis(IGM)involves many inflammatory cells and cytokines.PRL links neuroendocrine and immune systems and plays an active role in the inflammatory and immune processes.Based on the theory of PRL and combined with the latest research review at home and abroad,this paper aims to review the mechanism of action of PRL on IGM from the aspects of various inflammatory cells,cytokines and pathways,revealing the influence of PRL theory on IGM and the mechanism of action,so as to effectively control inflammation in the long-term. 展开更多
关键词 PROLACTIN idiopathic granulomatous mastitis IMMUNITY theoretical discussion mechanism of action
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Different imaging findings of inflammatory myofibroblastic tumor of the liver 被引量:3
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作者 xiao-fei liu Bao-Ming He +2 位作者 Xiao-Hui Ou-Yang Zhi-Zhong Wang Jia-Gui Su 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第40期5821-5825,共5页
Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with i... Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with imaging findings from positron emission tomography/computed tomography(PET/CT),contrastenhanced computed tomography(CECT) and contrastenhanced ultrasonography(CEUS).This report was the first to depict a PET/CT scan of a liver IMT that revealed an inhomogeneous,intense(fluorine 18)-fluoro-2-deoxy-D-glucose uptake.The CECT and CEUS images showed a hepatic artery supplying blood to the mass and necrosis.The characteristic histopathological features and the presence of spindle cells expressing smooth muscle actin,collagen fibers and lymphocytes allowed for the diagnosis of liver IMT.Recognizing such findings will help to achieve a correct diagnosis and may prevent inappropriate treatment. 展开更多
关键词 纤维母细胞 肌动蛋白 影像学 肝脏 炎症 计算机断层扫描 CECT 图像显示
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Treatment of bilateral granulomatous lobular mastitis during lactation with traditional Chinese medicine: A case report 被引量:4
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作者 Zhi-Yuan Li Xiao-Mei Sun +5 位作者 Jing-Wei Li xiao-fei liu Zi-Yuan Sun Han-Han Chen Yan-Ling Dong Xiao-Hui Sun 《World Journal of Clinical Cases》 SCIE 2021年第27期8249-8259,共11页
BACKGROUND Granulomatous lobular mastitis(GLM)is a type of benign chronic inflammatory disease that poses therapeutic challenges to healthcare providers.The diagnosis of GLM relies on tissue biopsy,and incorrect treat... BACKGROUND Granulomatous lobular mastitis(GLM)is a type of benign chronic inflammatory disease that poses therapeutic challenges to healthcare providers.The diagnosis of GLM relies on tissue biopsy,and incorrect treatment may lead to delayed diagnosis,considerable aesthetic damage,and even mastectomy.CASE SUMMARY We report the case of a 37-year-old Chinese woman who was lactating and had GLM in both breasts.At the time of treatment,the right breast had a mass of approximately 15 cm×11 cm,which was hard and had poor mobility.Multiple skin ulcerations and pus spills were also observed on the surface of the breast.The left breast had a mass of about 13 cm×9 cm,which was hard and had poor mobility.CONCLUSION Herein,we report a case of bilateral GLM in a lactating woman that was successfully treated with traditional Chinese medicine(TCM),without the requirement for surgery or other treatments.Therefore,TCM may have advantages in the nonsurgical treatment of GLM. 展开更多
关键词 Bilateral mammary gland Granulomatous lobular mastitis Lactation Traditional Chinese medicine Non-surgical treatment Case report
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紫精基离子型共轭微孔聚合物作为电子传输泵用于高效多硫化物捕获和转化
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作者 李海洋 李中山 +6 位作者 邱刚浩 张柔柔 王亚蕊 王凤 黄仁武 刘晓飞 臧双全 《Science Bulletin》 SCIE EI CAS CSCD 2024年第8期1071-1080,共10页
The commercialization of lithium-sulfur(Li-S)batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides(LiPSs).Herein,we reported a viologen-ba sed ionic conjugated mesoporou... The commercialization of lithium-sulfur(Li-S)batteries has been hindered by the shuttle effect and sluggish redox kinetics of lithium polysulfides(LiPSs).Herein,we reported a viologen-ba sed ionic conjugated mesoporous polymer(TpV-Cl),which acts as the cathode host for modifying Li-S batteries.The viologen component serves as a reversible electron conveyer,leading to a comprehensive enhancement in the adsorption of polysulfides and improved conversion rate of polysulfides during the electrochemical process.As a result,the S@TpV-PS cathode exhibits outstanding cycling performance,achieving 300 cycles at2.0 C(1 C=1675 mA g^(-1))with low decay rate of 0.032%per cycle.Even at a high sulfur loading of 4.0 mg cm^(-2),S@TpV-PS shows excellent cycling stability with a Coulombic efficiency of up to 98%.These results highlight the significant potential of S@TpV-PS in developing high-performance Li-S batteries. 展开更多
关键词 VIOLOGEN Conjugated mesoporous polymer Lithium-sulfur battery POLYSULFIDE Shuttle effect
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Conducting polymer-functionalized mesoporous metal-organic frameworks for high-performance Li-S battery
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作者 xiao-fei liu Ya-Rui Wang +2 位作者 Hong Chen Bo Li Shuang-Quan Zang 《Nano Research》 SCIE EI CSCD 2023年第4期4867-4873,共7页
It was known that mesoporous metal-organic frameworks(MOFs)with hierarchical pores and unsaturated metal sites can effectively inhibit the shuttle effect of lithium polysulfides in lithium-sulfur battery,however,the u... It was known that mesoporous metal-organic frameworks(MOFs)with hierarchical pores and unsaturated metal sites can effectively inhibit the shuttle effect of lithium polysulfides in lithium-sulfur battery,however,the unsatisfactory structural stability and electrical conductivity limit the application of mesoporous MOFs(MMOFs)in Li-S batteries.Aiming at sensible solutions,the conductive polyaniline(PANI)was incorporated into the MMOF to enhance the discharge capacity and the cycling stability of proposed Li-S batteries,as the stability and the conductivity of the MMOF cathode was improved simultaneously.The activated MMOF-PANI provides physical and chemical adsorption of polysulfides against their shuttle effect.Moreover,the introduction of PANI into the channels of MMOF effectively improves the conductivity of MMOF,thus improving the electrochemical performance of the MMOF-PANI-based batteries.Benefiting from these synergetic effects,the S@MMOF-PANI cathode delivers improved electrochemical performance including excellent rate performance and cycling stability.The battery shows an initial capacity of 777.7 mAh·g^(−1)at 2.0 C and a low decay rate of 0.06%per cycle in 1,000 cycles and approximately a repeatable rate performance. 展开更多
关键词 metal-organic framework CONDUCTIVITY MESOPOROUS shuttle effect Li-S battery
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Spinning microresonator-induced chiral optical transmission
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作者 Lu Bo xiao-fei liu +1 位作者 Chuan Wang Tie-Jun Wang 《Frontiers of physics》 SCIE CSCD 2023年第1期175-183,共9页
Chiral quantum optics is a new research area in light-matter interaction that depends on the direction of light propagation and offers a new path for the quantum regulation of light-matter interactions.In this paper,w... Chiral quantum optics is a new research area in light-matter interaction that depends on the direction of light propagation and offers a new path for the quantum regulation of light-matter interactions.In this paper,we study a spinning Kerr-type microresonator coupled withΛ-type atom ensembles,which are driven in opposite directions to generate asymmetric photon statistics.We find that a photon blockade can only be generated by driving the spinning resonator on right side without driving the spinning microresonator from the left side,resulting in chirality.The coupling strength between system modes can be precisely controlled by adjusting the detuning amount of the atomic pump field.Because of the splitting of the resonant frequency generated by the Fizeau drag,the destructive quantum interference generated in right side drive prevents the nonresonant transition path of state|1,0⟩to state|2,0⟩.This direction-dependent chiral quantum optics is expected to be applied to chiral optical devices,single-photon sources and nonreciprocal quantum communications. 展开更多
关键词 chiral quantum optics spinning microresonator nonreciprocal photon blockade
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Effect of Dialysis on Antiplatelet Drug Efficacy in Uremic Patients with Coronary Heart Disease 被引量:6
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作者 Dong-Liang Fu Ting-Ting Zhao +9 位作者 Wen-Hua Peng Peng Yang xiao-fei liu Hu Zhang Xian-Lun Li Yong Wang Jin-Gang Zheng Yan-Xiang Gao Hong-Kai Lu Qi Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2017年第16期1914-1918,共5页
Background: Coronary intervention therapy is the main treatment for uremic patients with coronary heart disease. The studies on whether dialysis reduces the efficacy of dual antiplatelet drugs are limited. The aim of... Background: Coronary intervention therapy is the main treatment for uremic patients with coronary heart disease. The studies on whether dialysis reduces the efficacy of dual antiplatelet drugs are limited. The aim of this study was to examine the effect of dialysis on antiplatelet drugs in uremic patients with coronary heart disease. Methods: This study included 26 uremic patients who had undergone percutaneous coronary intervention in China-Japan Friendship Hospital from November 2015 to May 2017. We examined their thromboelastography results before and after hemodialysis. Self-paired t-tests were employed to analyze changes in the inhibition rate of platelet aggregation. Results: The mean inhibition rates of arachidonic acid-induced platelet aggregation before and after hemodialysis were 82.56 ± 2.79% and 86.42±3.32%, respectively (t =-1.278, P = 0.213). The mean inhibition rates of adenosine diphosphate-induced platelet aggregation before and after hemodialysis were 67.87± 5.10% and 61.9± 5.90%, respectively (t = 1.425, P = 0.167). There was no significant difference in the inhibition rates ofplatelet aggregation before or after hemodialysis. These results also applied to patients with different sensitivity to aspirin and clopidogrel. Conclusion: Dialysis did not affect the antiplatelet effects of aspirin and clopidogrel in uremic patients with coronary heart disease. 展开更多
关键词 Antiplatelet Drug Coronary Intervention DIALYSIS THROMBOELASTOGRAPHY
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Possible Mechanism of Therapeutic Effect of 3-Methyl-l-phenyl-2-pyrazolin-5-one and Bone Marrow Stromal Cells Combination Treatment in Rat Ischemic Stroke Model 被引量:5
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作者 Li-Hua Shen Jin Chen +5 位作者 Hua-Chao Shen Min Ye xiao-fei liu Wen-Sen Ding Ya-Feng Sheng Xin-Sheng Ding 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第12期1471-1476,共6页
Background: The functional improvement following bone marrow stromal cells (BMSCs) transplantation after stroke is directly related to the number of engrafted cells and neurogenesis in the injured brain. Here, we t... Background: The functional improvement following bone marrow stromal cells (BMSCs) transplantation after stroke is directly related to the number of engrafted cells and neurogenesis in the injured brain. Here, we tried to evaluate whether 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186), a free radical scavenger, might influence BMSCs migration to ischemic brain, which could promote neurogenesis and thereby enhance treatment effects after stroke. Methods: Rat transient middle cerebral artery occlusion (MCAO) model was established. Two separate MCAO groups were administered with either MC1-186 or phosphate-buffered saline (PBS) solution to evaluate the expression of stromal cell-derived factor-1 (SDF-1) in ischemic brain, and compared to that in sham group (n 5/group/time point[at 1,3, and 7 days after operation]). The content ofchemokine receptor-4 (CXCR4, a main receptor of SDF-I) at 7 days after operation was also observed on cultured BMSCs. Another four MCAO groups were intravenously administered with either PBS, MCI-186, BMSCs (2 ×106), or a combination of MCI-186 and BMSCs (n = 10/ group). 5-bromo-2-deoxyuridine (BrdU) and Nestin double-immunofluorescence staining was performed to identity the engrafted BMSCs and neuronal differentiation. Adhesive-removal test and foot-fault evaluation were used to test the neurological outcome. Results: MC1-186 upregulated the expression ofSDF- 1 in ischemic brain and CXCR4 content in BMSCs was enhanced after hypoxic stimulation. When MCAO rats were treated with either MCI- 186, BMSCs, or a combination ofMCI- 186 and BMSCs, the neurologic function was obviously recovered as compared to PBS control group (P 〈 0.01 or 0.05, respectively). Combination therapy represented a further restoration, increased the number of BMSCs and Nestin- cells in ischemic brain as compared with BMSCs monotherapy (P 〈 0.01). The number ofengrafted-BMSCs was correlated with the density of neuronal cells in ischemic brain (r = 0.72, P 〈 0.01 ) and the improvement of foot-thult (r = 0.70, P 〈 0.0 t ). Conclusion: MCI- 186 might promote BMSCs migration to the ischemic brain, amplify the neurogenesis, and improve the effects of cell therapy. 展开更多
关键词 3-Methyl-l-phenyl-2-pyrazolin-5-one Bone Marrow Stromal Cells Ischemic Stroke Neurogenesis Stromal Cell-derivedFactor- 1
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Three-dimensional super-resolution longitudinal magnetization spot arrays 被引量:3
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作者 Zhong-Quan Nie Han Lin +8 位作者 xiao-fei liu Ai-Ping Zhai Yan-Ting Tian Wen-Jie Wang Dong-Yu Li Wei-Qiang Ding Xue-Ru Zhang Ying-Lin Song Bao-Hua Jia 《Light(Science & Applications)》 SCIE EI CAS CSCD 2017年第1期630-637,共8页
We demonstrate an all-optical strategy for realizing spherical three-dimensional(3D)super-resolution(∼λ3/22)spot arrays of pure longitudinal magnetization by exploiting a 4πoptical microscopic setup with two high n... We demonstrate an all-optical strategy for realizing spherical three-dimensional(3D)super-resolution(∼λ3/22)spot arrays of pure longitudinal magnetization by exploiting a 4πoptical microscopic setup with two high numerical aperture(NA)objective lenses,which focus and interfere two modulated vectorial beams.Multiple phase filters(MPFs)are designed via an analytical approach derived from the vectorial Debye diffraction theory to modulate the two circularly polarized beams.The system is tailored to constructively interfere the longitudinal magnetization components,while simultaneously destructively interfering the azimuthal ones.As a result,the magnetization field is not only purely longitudinal but also super-resolved in all three dimensions.Furthermore,the MPFs can be designed analytically to control the number and locations of the super-resolved magnetization spots to produce both uniform and nonuniform arrays in a 3D volume.Thus,an all-optical control of all the properties of light-induced magnetization spot arrays has been demonstrated for the first time.These results open up broad applications in magnetic-optical devices such as confocal and multifocal magnetic resonance microscopy,3D ultrahigh-density magneto-optic memory,and light-induced magneto-lithography. 展开更多
关键词 inverse Faraday effect longitudinal magnetization magnetic-optical devices MAGNETO-OPTICS vectorial beams vectorial Debye diffraction theory
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Rapid and high precision measurement of opto-thermal relaxation with pump-probe method 被引量:2
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作者 Tao Wang xiao-fei liu +3 位作者 Yunqi Hu Guoqing Qin Dong Ruan Gui-Lu Long 《Science Bulletin》 SCIE EI CSCD 2018年第5期287-292,共6页
Opto-thermal relaxation is one of the most important properties of nonlinear optical materials.Rapid and high precision measurement of this parameter is vital in both fundamental research and applications.Current meas... Opto-thermal relaxation is one of the most important properties of nonlinear optical materials.Rapid and high precision measurement of this parameter is vital in both fundamental research and applications.Current measurement uses either complicated structure with poor precision or high power heating source with low efficiency.Here,we propose a pump-probe method(PPM) to optically measure the thermal relaxation using whispering gallery mode(WGM) microcavities.When the pump laser shines on a microcavity,the materials absorb the input power resonantly and heat up.Then the heat dissipates from the cavities to the surroundings.The opto-thermal effect induces a refractive index change reflected in the signal light transmission spectra.By analyzing the curve character of the transmission spectra of the signal response in the spontaneous relaxation process,the thermal relaxation time can be rapidly measured with high precision.Additionally,we systematically verify the PPM using microtoroids under various pump powers and at various locking points of the signal laser mode.The small rate of refractive index changes($10à8) can be discerned with an input pump power as low as 11.816 l W.Hence,the PPM can be used to detect refractive index perturbation,like gas or liquid sensing,temperature fluctuations with ultra-high sensitivity and be applied to optical materials analysis efficiently. 展开更多
关键词 MICROCAVITIES Opto-thermal effect Optical materials THERMAL RELAXATION SENSING PUMP-PROBE
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Rational designed isostructural MOF for the charge-discharge behavior study of super capacitors 被引量:1
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作者 Hong Chen xiao-fei liu +2 位作者 Hai-Yang Li Peng Peng Shuang-Quan Zang 《Nano Research》 SCIE EI CSCD 2022年第7期6208-6212,共5页
In recent years,the rapid charge-discharge property of super capacitors based on metal-organic frameworks(MOFs)has seen excellent applications in energy storage equipment.However,the purposeful design of high-performa... In recent years,the rapid charge-discharge property of super capacitors based on metal-organic frameworks(MOFs)has seen excellent applications in energy storage equipment.However,the purposeful design of high-performance electrodes for MOFderived super capacitors is still an urgent problem that needs to be solved.Herein,we rationally design and prepare three MOFs with the same crystal configuration and controllable functional groups.Through the combination of rigorous experiment and calculation,we have verified the effects of the specific surface area of the electrode material as well as the binding energy between the electrode material and the electrolyte ions on the performance of the super capacitor.This work not only extends the application of MOFs,but also provides a model-material platform for the study of charge–discharge behavior of MOF-based super capacitors,creating a way of thinking for the selection and design of MOF materials for energy storage applications. 展开更多
关键词 Eu-metal-organic framework(Eu-MOF) super capacitor rational design controllable charge-discharge behavior
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The analysis of high-order sideband signals in optomechanical system
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作者 Xiao-Ran Xiong Yong-Pan Gao +3 位作者 xiao-fei liu Cong Cao Tie-Jun Wang Chuan Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第9期95-98,共4页
Cavity optomechanics[1,2]reveals the interaction between the optical mode and mechanical mode via radiation pressure.Recently,optomechanics is widely studied as an ideal interface between the optical field and microwa... Cavity optomechanics[1,2]reveals the interaction between the optical mode and mechanical mode via radiation pressure.Recently,optomechanics is widely studied as an ideal interface between the optical field and microwave field,and the advantages of optomechanics show great potential for ap- 展开更多
关键词 边带 信号 系统 机械模式 相互作用 应用程序 信息处理 光模式
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Thioxanthene-9-thione Mediated MMA Polymerization
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作者 Xu Yan Guan Wang +3 位作者 Li-Hua Zhang Li Wang xiao-fei liu Wan-Tai Yang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第7期805-810,共6页
In the "cycloketyl radical mediated living polymerization" (CMP) process, a cycloketyl compound, [9,9']bixanthenyl-9,9' diol (BIXAN) was ultilized as initiator and mediator. The cycloketyl (CK) radical was u... In the "cycloketyl radical mediated living polymerization" (CMP) process, a cycloketyl compound, [9,9']bixanthenyl-9,9' diol (BIXAN) was ultilized as initiator and mediator. The cycloketyl (CK) radical was used as the dormant radical to achieve the increase of molecular weight. Herein, a series of cycloketyl thioketones were synthesised by Lawesson's reagent by one step reaction with high yeild, and we found that, when a special cyeloketyl thioketone compound, thioxanthene-9-thione (TXT), was added to a routine radical polymerization system, TXT could capture chain radical, and simultaneously formed an radical analogous to CK radical in structure, which could trigger the growth of polymer chains. This simple system was efficient to initiate the polymerization of methyl methacrylate (MMA) and in all cases the molecular weights increased with the increase of conversions. By the end-group analysis with 1H-NMR and MALDI-TOF MS, it was confirmed that the P-STXT radical was used to control the polymerization. The re-initiating reactions were achieved when PMMA was used as the macro-initiator. 展开更多
关键词 Thioxanthene-9-thione Lawesson's reagent Methyl methacrylate Radical polymerization
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Recent advances in electrochemical carboxylation reactions using carbon dioxide
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作者 xiao-fei liu Ke Zhang +2 位作者 Li Tao Xiao-Bing Lu Wen-Zhen Zhang 《Green Chemical Engineering》 2022年第2期125-137,共13页
From the viewpoint of abundance,economy,non-toxicity,and renewability,CO_(2) is the ideal C1 synthon in organic synthetic chemistry.Utilizing CO_(2) for chemical conversion to synthesize highly value-added fine chem-i... From the viewpoint of abundance,economy,non-toxicity,and renewability,CO_(2) is the ideal C1 synthon in organic synthetic chemistry.Utilizing CO_(2) for chemical conversion to synthesize highly value-added fine chem-icals is of great significance.Organic electrochemical synthesis that employs electrons as redox reagents to achieve selective oxidation or reduction has attracted much attention in the past decades.In this review,recent advances in the electrochemical carboxylations using CO_(2) from the perspective of organic synthesis will be summarized.We give an overview about the research progress of electrocarboxylation reactions according to the classification of substrates,such as alkenes,organic(pseudo)halides,aldehydes,ketones,and imines.The carb-anions produced by cathodic reduction are important intermediates in the electrocarboxylation reactions using CO_(2). 展开更多
关键词 Carbon dioxide Organic electrochemical synthesis CARBOXYLATION Green chemistry Carboxylic acid
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