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Antidepressant effects of Yuanzhi (Polygalae Radix) extract on chronic unpredictable mild stress-induced depression in rats: modulation of the NLRP3 inflammasome and NF-κB pathway
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作者 CHEN Yuzhen ZHAO Yongzhi +4 位作者 ZHANG Yiwen CHEN Fang Iqbal Choudhary Muhammad LIU Xinmin JIANG Ning 《Digital Chinese Medicine》 CAS CSCD 2024年第2期184-194,共11页
Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total ... Objective To investigate the antidepressant effects of Yuanzhi(Polygalae Radix;PR)aqueous extract on chronic unpredictable mild stress(CUMS)-induced depression rat models and the underlying mechanisms.Methods A total of 40 male Sprague Dawley(SD)rats were randomly divided into control;model;low dose of PR(PR-L;0.5 g/kg);high dose of PR(PR-H;1 g/kg);and fluoxetine(10 mg/kg)groups;with 8 rats in each group.Except for the rats in control group;those in the other four groups underwent CUMS-induced depression modeling.PR and fluoxetine were administered intragastrically once daily;30 min prior to the CUMS procedure;for 14 consecu-tive days until the behavioral tests were performed.After CUMS modeling;the sucrose prefer-ence test(SPT);open field test(OFT);novelty-suppressed feeding test(NSFT);forced swim test(FST);and tail suspension test(TST)were employed to assess the pharmacological ef-fects of PR on the mitigation of depressive-like behaviors in rat models.Additionally;the en-zyme-linked immunosorbent assay(ELISA)was utilized to quantify the serum levels of tumor necrosis factor(TNF)-α;interleukin(IL)-6;and IL-1βin the rats.Western blot analysis was al-so conducted to evaluate the protein expression levels of nuclear factor kappa-B(NF-κB);in-ducible nitric oxide synthase(iNOS);cyclooxygenase-2(COX-2);nucleotide-binding oligomerization domain(NOD)-like receptor family pyrin domain containing 3(NLRP3);apoptosis-associated speck-like protein containing caspase recruitment domain(ASC);and caspase-1 in the hippocampal tissues of the rats.Immunofluorescence staining was per-formed to observe the morphological changes in ionized calcium-binding adapter molecule 1 positive(Iba-1+)cells in the dentate gyrus(DG)of rats with CUMS-induced depression.Results(i)Treatment with PR-H and fluoxetine resulted in significant enhancements in both the total distance and time the rats moved during tests(P<0.01 and P<0.05;respectively).Post-administration of PR-H and fluoxetine also led to statistically significant increase in su-crose preference among rats(P<0.05).Besides;PR-L;PR-H;and fluoxetine treatment markedly decreased the latency of ingestion(P<0.05;P<0.05;and P<0.01;respectively).As observed from the FST;PR-L;PR-H;and fluoxetine presented antidepressant effects on rats with CUMS-induced depression;leading to the reduction in time of their immobility(P<0.05;P<0.01;and P<0.01;respectively).The results of TST indicated reduced immobility time in rats receiving PR-H and fluoxetine treatment as well(P<0.01).(ii)Rats in model group showed an increase in the levels of Iba-1+microglia in their left and right brains in compari-son with control group(P<0.01).However;such increase was negated post PR treatment(P<0.01).Treatment with PR-L;PR-H;and fluoxetine considerably reduced the levels of inflam-matory factors(TNF-α;IL-1β;and IL-6;P<0.01).In addition;treatment of PR-L and PR-H ef-fectively counteracted the elevated levels of NLRP3;ASC;and caspase-1;and markedly down-regulated the expression levels of phosphorylated p65(p-p65);COX-2;and iNOS in rats’hip-pocampus(P<0.01).Conclusion Collectively;these findings indicate that PR exerts an antidepressant effect on rats with CUMS-induced depression partially through the modulation of the NLRP3 and NF-κB signaling pathways. 展开更多
关键词 DEPRESSION Yuanzhi(Polygalae Radix) Chronic unpredictable mild stress(CUMS) Proinflammatory cytokine Neuroinflammatory
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Binding Energies of Screened Excitons in a Strained(111)-Oriented Zinc-Blende GaN/AlGaN Quantum Well Under Hydrostatic Pressure 被引量:6
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作者 哈斯花 班士良 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期234-239,共6页
We investigate the binding energies of excitons in a strained (111)-oriented zinc-blende GaN/Al0.3 Ga0.7 N quantum well screened by the electron-hole (e-h) gas under hydrostatic pressure by combining a variational... We investigate the binding energies of excitons in a strained (111)-oriented zinc-blende GaN/Al0.3 Ga0.7 N quantum well screened by the electron-hole (e-h) gas under hydrostatic pressure by combining a variational method and a selfconsistent procedure. A built-in electric field produced by the strain-induced piezoelectric polarization is considered in our calculations. The result indicates that the binding energies of excitons increase nearly linearly with pressure,even though the modification of strain with hydrostatic pressure is considered, and the influence of pressure is more apparent under higher e-h densities. It is also found that as the density of an e-h gas increases,the binding energies first increase slowly to a maximum and then decrease rapidly when the e-h density is larger than about 1 ×10^11 cm^-2. The excitonic binding energies increase obviously as the barrier thickness decreases due to the decrease of the built-in electric field. 展开更多
关键词 EXCITON strained zinc-blende quantum well pressure screened effect
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Approximate Well Width and Optical Gain Formulas of 1 .555μm In_(1-x-y )Ga_y Al_x As Compressively Strained Quantum- Well Laser 被引量:2
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作者 张冶金 陈维友 +2 位作者 蒋恒 刘彩霞 刘式墉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第1期11-17,共7页
Using Harrison's model and anisotropic parabolic approximation,the band structure of In1- x- y Gay Alx As compressively strained quantum wells is calculated.To design lasers with1.55μm wavelength,it is necessary... Using Harrison's model and anisotropic parabolic approximation,the band structure of In1- x- y Gay Alx As compressively strained quantum wells is calculated.To design lasers with1.55μm wavelength,it is necessary to an- alyze the well width,differential gain,transparency carrier density and the characteristic gain for an arbitrary com- position.Some useful empirical formulas are also presented. 展开更多
关键词 In1- x- y Gay Alx As QW linear gain differential gai
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GSMBE-Grown InGaAs/InGaAsP Strained Quantum Well Lasers at 1.84 Micron Wavelength 被引量:1
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作者 柏劲松 方祖捷 +3 位作者 张云妹 陈高庭 李爱珍 陈建新 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期126-129,共4页
GSMBE grown 1 84 micron wavelength InGaAs/InGaAsP/InP strained quantum well lasers are reported. Lasers with 800 micron long cavity and 40 micron wide planar electrical stripe have been operated under the pulsed r... GSMBE grown 1 84 micron wavelength InGaAs/InGaAsP/InP strained quantum well lasers are reported. Lasers with 800 micron long cavity and 40 micron wide planar electrical stripe have been operated under the pulsed regime at room temperature. At 20℃, the threshold current density is 3 8kA/cm 2 and the external different quantum efficiency is 9 3%. 展开更多
关键词 GSMBE midinfrared band strained quantum well laser
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Compressively Strained InGaAs/InGaAsP Quantum Well Distributed Feedback Laser at 1.74μm 被引量:1
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作者 潘教青 王圩 +4 位作者 朱洪亮 赵谦 王宝军 周帆 王鲁峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1688-1691,共4页
The compressively strained InGaAs/InGaAsP quantum well distributed feedback laser with ridge-wave- guide is fabricated at 1.74μm. It is grown by low-pressure metal organic chemical vapor deposition(MOCVD). A strain... The compressively strained InGaAs/InGaAsP quantum well distributed feedback laser with ridge-wave- guide is fabricated at 1.74μm. It is grown by low-pressure metal organic chemical vapor deposition(MOCVD). A strain buffer layer is used to avoid indium segregation. The threshold current of the device uncoated with length of 300μm is 11.5mA. The maximum output power is 14mW at 100mA. A side mode suppression ratio of 35.5dB is obtained. 展开更多
关键词 DFB laser compressive strain quantum well
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夏季平原负荷强行军对机体内分泌系统的影响
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作者 蔡万春 尤柯 李晓卫 《西北国防医学杂志》 CAS 1991年第3期15-16,共2页
本文报告了35名战士夏季在平原地区负荷强行军中16项内分泌指标的变化。结果表明下丘脑-垂体应激反应、甲状腺功能、肾上腺皮质和髓质功能增强;胰岛素分泌抑制;性腺功能无明显变化。经16小时休息后随着应激子的消除,上述内分泌系统的变... 本文报告了35名战士夏季在平原地区负荷强行军中16项内分泌指标的变化。结果表明下丘脑-垂体应激反应、甲状腺功能、肾上腺皮质和髓质功能增强;胰岛素分泌抑制;性腺功能无明显变化。经16小时休息后随着应激子的消除,上述内分泌系统的变化可恢复正常。 展开更多
关键词 内分泌 激反 应激子
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Optimization Design of Active Structure of Strained MQW DFB Lasers
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作者 张冶金 朱林 +5 位作者 高志国 陈明华 董毅 陈维友 刘式墉 谢世钟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第1期6-10,共5页
The well number and the cavity length of 1.55μm wavelength In 1-x-y Ga y Al x As MQW DFB lasers are optimized using a simple model.A low threshold,maximum operating temperature of 550~560K,and high relaxat... The well number and the cavity length of 1.55μm wavelength In 1-x-y Ga y Al x As MQW DFB lasers are optimized using a simple model.A low threshold,maximum operating temperature of 550~560K,and high relaxation oscillation frequency of over 30GHz MQW DFB laser is presented. 展开更多
关键词 In 1-x-y Gay Alx As QW laser DFB differential gain optimization design
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THE SCATTERING THEORY OF IONIC CONDUCTIVITY OF TERNARY GLASS
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作者 唐多强 宋威 陈荣金 《Transactions of Tianjin University》 EI CAS 1997年第2期110-112,共3页
The physical expression of electrical conductivity of ternary glass can be obtained by the physical scattering theory of conducting ions by the defects in the glass. The scattering area of ion by the nucleus is given ... The physical expression of electrical conductivity of ternary glass can be obtained by the physical scattering theory of conducting ions by the defects in the glass. The scattering area of ion by the nucleus is given by the law of Rutherford in atomic physics. By this theory, the physical meaning of the microprocess of ionic conductivity of ternary glass is apparent. 展开更多
关键词 activation energy scattering effect electric conductivity of ions
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E-Supply Chain Incentive and Coordination Based on Revenue Sharing Contract 被引量:4
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作者 常志平 蒋馥 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第1期42-48,共7页
This paper took the buyer-biased electronic market as an example, where multiple suppliers selling short-life-cycle products are bidding for an order from a powerful buyer with stochastic customer demand. It used a si... This paper took the buyer-biased electronic market as an example, where multiple suppliers selling short-life-cycle products are bidding for an order from a powerful buyer with stochastic customer demand. It used a single period newsvendor model to analyze the decision of supplied and buyers to do or not do business online. The results suggest that lack of Incentive is the key factor of B2B electronic markets failure. At the same time, it designed a revenue sharing contract to coordinate the E-supply chain in order to prevent failure of E-market. 展开更多
关键词 electronic markets E-supply chain INCENTIVE COORDINATION supply chain contracts
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Importance of Monitoring of Emotional Stress and Physiological Functions of Humans during the Night Sleep 被引量:1
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作者 Evgeny A. Yumatov Sergey S. Pertsov 《Journal of Pharmacy and Pharmacology》 2017年第5期275-281,共7页
The diagnosis of disease and prescription of therapy are mainly realized through the control of physiological functions in humans during wakefulness. However, little attention is paid to evaluate the functional state ... The diagnosis of disease and prescription of therapy are mainly realized through the control of physiological functions in humans during wakefulness. However, little attention is paid to evaluate the functional state of a patient in sleep. The efficiency of prescribed medicines is also determined in wakefulness. The effects of these drugs during sleep are usually out-of-sight of a physician. Human psychoemotional state during wakefulness is closely related to sleep. Various serious disturbances in physiological functions appear during the night sleep. They include cardiovascular disorders (hypertensive crisis, myocardial infarction, arrhythmias, stroke, etc.), which may cause sudden death. A large body of evidence shows that stress is followed by sleep disorders. They serve as a factor, which contributes to the development of stress. It should be noted that sleep is the major anti-stress factor. The vicious circle is formed, which can be revealed by a complex control of human physiological functions during wakefulness and sleep. We developed a new methodology and constructed an information-and-equipment device for monitoring of vital physiological functions of humans during sleep in a real everyday life. This approach holds much promise for the diagnosis of disease and evaluation of therapeutic efficacy. 展开更多
关键词 SLEEP information medicine medical devices vital functions.
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Size Effect of a Negatively Charged Exciton in a Two-Dimensional Quantum Dot
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作者 LIU Chao XIE Wen-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期353-357,共5页
In this paper we study a negatively charged exciton (NCE), which is trapped by a two-dimensional (2D) parabolic potential. By using matrix diagonalization techniques, the correlation energies of the low-lying stat... In this paper we study a negatively charged exciton (NCE), which is trapped by a two-dimensional (2D) parabolic potential. By using matrix diagonalization techniques, the correlation energies of the low-lying states with L=0, 1, and 2 are calculated as a function of confinement strength. We find that the size effects of different states are different. This phenomenon can be explained as a hidden symmetry, which is originated purely from symmetry. Based on symmetry, the features of the low-lying states are discussed in the influence of the 2D parabolic potential well. It is found that the confinement may cause accidental degeneracies between levels with different low-excited states. It is shown that the effect of quantum confinement on the binding energy of the heavy hole is stronger than that of a light hole. 展开更多
关键词 quantum dot charged exciton size effect energy spectrum SYMMETRY
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Antioxidant responses and salt stress tolerance of Aloe vera irrigated by seawater with different salinity
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作者 金赞敏 Liu Zhaopu +1 位作者 Wang Changhai Gong Weijia 《High Technology Letters》 EI CAS 2007年第3期332-336,共5页
The variations of antioxidant enzyme activities including superoxide dismutase (SOD: EC 1.15.1.1), peroxidase (POD: EC 1.11.1.7) and catalase (CAT: EC 1.11.1.6), lipid peroxidation and major electrolytes in A... The variations of antioxidant enzyme activities including superoxide dismutase (SOD: EC 1.15.1.1), peroxidase (POD: EC 1.11.1.7) and catalase (CAT: EC 1.11.1.6), lipid peroxidation and major electrolytes in Aloe vera irrigated for three years with seawater having different salinity were studied. The results indicate that POD activity increased significantly at 10% seawater level, whereas decreased at higher seawater levels. The SOD activity decreased with increasing seawater concentration except for treatment with 100% seawater (denoted as T100%) under long-term salt stress. Salinity decreased CAT activity,and increased lipid peroxidation and cell membrane injury. In addition, Ca^2+ content was high in Aloe irrigated by seawater of low salinity level, but low in Aloe irrigated by seawater of high salinity level. An opposite trend was observed for the effect of seawater on Na^+ content of plants. K^+ and Mg^2+ contents remain relatively stable under various seawater levels, which benefit plant growth. 展开更多
关键词 Aloe vera antioxidant enzymes cell membrane stability inorganic cations malondi-aldehyde salt stress
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Infrared Spectroscopy of Neutral Clusters Based on a Vacuum Ultraviolet Free Electron Laseri 被引量:1
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作者 Gang Li Chong Wang +4 位作者 Hui-jun Zheng Tian-tong Wang Hua Xie Xue-ming Yang Ling Jiang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第1期51-60,I0011,共11页
Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the ab... Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the absence of a charge makes it di伍cult for the size selection and detection.Infrared(IR)spectroscopy based on threshold photoionization using a tunable vacuum ultraviolet free electron laser(VUV-FEL)has recently been developed in the lab.The IR-VUV depletion and IR+VUV enhancement spectroscopic techniques open new avenues for size-selected IR spectroscopies of a large variety of neutral clusters without confinement(i.e.,an ultraviolet chromophore,a messenger tag,or a host matrix).The spectroscopic principles have been demonstrated by investigations of some neutral water clusters and some metal carbonyls.Here,the spectroscopic principles and their applications for neutral clusters are reviewed. 展开更多
关键词 CLUSTERS Infrared spectroscopy Vacuum ultraviolet free electron laser STRUCTURES Reaction mechanisms
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Polaronic Effects of an Exciton in a Cylindrical Quantum Wire 被引量:1
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作者 WANGRui-Qiang XIEHong-Jing GUOKang-Xian YUYou-Bin DENGYong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期169-174,共6页
The effects of exciton-optical phonon interaction on the binding energy and the total and reduced effective masses of an exciton in a cylindrical quantum wire have been investigated. We adopt a perturbative-PLL [T.D. ... The effects of exciton-optical phonon interaction on the binding energy and the total and reduced effective masses of an exciton in a cylindrical quantum wire have been investigated. We adopt a perturbative-PLL [T.D. Lee,F. Low, and D. Pines, Phys. Rev. B90 (1953) 297] technique to construct an effective Hamiltonian and then use a variational solution to deal with the exciton-phonon system. The interactions of exciton with the longitudinal-optical phonon and the surface-optical phonon have been taken into consideration. The numerical calculations for GaAs show that the influences of phonon modes on the exciton in a quasi-one-dimensional quantum wire are considerable and should not be neglected. Moreover the numerical results for heavy- and light-hole exciton are obtained, which show that the polaronic effects on two types of excitons are very different but both depend heavily on the sizes of the wire. 展开更多
关键词 exciton binding energy polaronic effect cylindrical quantum wire
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Stark Effect Dependence on Hydrogenic Impurities in GaAs Parabolic Quantum-Well Wires 被引量:1
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作者 WANG Sheng WEI Guo-Zhu HAN Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期953-959,共7页
The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-d... The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. We define an effective radius Pen of a cylindrical QWW, which can describe the strength of the lateral confinement. For the ground state, the position of the largest probability density of electron in x-y plane is located at a point, while for the lowest excited state, is located on a circularity whose radius is Pen. The point and circularity are pushed along the left haft of the center axis of the quantum-well wire by the electric field dire ted along the right half. When an impurity is located at the point or within the circularity, the ground-state or lowest excited-state binding energies are the largest; when the impurity is apart from the point or circularity, the ground-state or lowest excited-state binding energies start to decrease. 展开更多
关键词 hydrogenic impurity quantum-well wire magnetic field binding energy
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Pressure-Induced Shifts of R1 and R2 Lines of YAG:Cr3+
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作者 ZHANG Zheng-Jie MA Dong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期754-760,共7页
By means of improved ligand-field theory, the "pure electronic" pressure-induced shifts (PS's) and the PS's due to electron-phonon interaction (EPI) of R1 line and R2 line of YAG:Cr^3+ have been calculated, ... By means of improved ligand-field theory, the "pure electronic" pressure-induced shifts (PS's) and the PS's due to electron-phonon interaction (EPI) of R1 line and R2 line of YAG:Cr^3+ have been calculated, respectively. The calculated results are in very good agreement with the experimental data. It is demonstrated that the admixture of │t^2 2(^3T1)e^4T2〉 and │t^3 2 ^2E〉 bases in the wavefunction of RI level of YAG:Crs+ and its change with pressure play a key role for the PS of RI line. The behaviors of the "pure electronic" PS of RI line and the PS of RI line due to EPI are different. It is the combined eEect of them that gives rise to the total PS of R1 line, which has satisfactorily explained the experimental results. The systematic analyses and comparisons between the feature of R1-line PS of YAG:Cr^3+ and the ones of three laser crystals (GSGG:Cr^3+, GGG:Cr^3+ and ruby) have been made, and the origin of the difference between them has been revealed. 展开更多
关键词 high-pressure effect electron-phonon interaction R lines admixture of |t22(3T1)e4T2〉 and |t322E〉 laser crystals
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Photochemistry of Potassium Ferrocyanide and its Reaction with Uridine 5′-monophosphate in Aqueous Solution under Ultraviolet Irradiation
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作者 Song-qiu Yang Yan Zhang Yan-ni Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第5期764-773,I0014-I0022,I0011,I0012,共21页
The photochemical reaction of potassium ferrocyanide(K_(4)Fe(CN)_(6))exhibits excitation wavelength dependence and non-Kasha rule behavior.In this study,the excited-state dynamics of K_(4)Fe(CN)_(6) were studied by tr... The photochemical reaction of potassium ferrocyanide(K_(4)Fe(CN)_(6))exhibits excitation wavelength dependence and non-Kasha rule behavior.In this study,the excited-state dynamics of K_(4)Fe(CN)_(6) were studied by transient absorption spectroscopy.Excited state electron detachment(ESED)and photoaquation reactions were clarified by comparing the results of 260,320,340,and 350 nm excitations.ESED is the path to generate a hydrated electron(e^(−)_(aq)).ESED energy barrier varies with the excited state,and it occurs even at the first singlet excited state(^(1)T_(1g)).The ^(1)T_(1g) state shows∼0.2 ps lifetime and converts into triplet[Fe(CN)_(6)]4−by intersystem crossing.Subsequently,3Fe(CN)_(5)]^(3-)appears after one CN−ligand is ejected.In sequence,H2O attacksFe(CN)_(5)]^(3-)to generate[Fe(CN)_(5)H_(2)O]^(3−)with a time constant of approximately 20 ps.The ^(1)T_(1g) state and e−aq exhibit strong reducing power.The addition of uridine 5′-monophosphate(UMP)to the K_(4)Fe(CN)_(6) solution decrease the yield of e−aq and reduce the lifetimes of the e−aq and ^(1)T_(1g) state.The obtained reaction rate constant of ^(1)T_(1g) state and UMP is 1.7×10^(14)(mol/L)^(−1)·s^(−1),and the e−aq attachment to UMP is∼8×10^(9)(mol/L)^(−1)·s^(−1).Our results indicate that the reductive damage of K_(4)Fe(CN)_(6) solution to nucleic acids under ultraviolet irradiation cannot be neglected. 展开更多
关键词 Ultrafast spectroscopy Photoaquation Electron detachment Excited state dynamics Ferrous hexacyanides
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Laser Ablation Atomic Beam Apparatus with Time-Sliced Velocity Map Imaging for Studying State-to-State Metal Reaction Dynamics
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作者 董常武 刘嘉兴 +1 位作者 李芳芳 王凤燕 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期99-104,I0002,共7页
We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic be... We report a newly constructed laser ablation crossed molecular beam apparatus, equipped with time-sliced velocity map imaging technique, to study state-to-state metal atom reaction dynamics. Supersonic metal atomic beam is generated by laser vaporization of metal rod, and free expansion design without gas flow channel has been employed to obtain a good quality of metal atomic beam. We have chosen the crossed-beam reaction Al+O2 to test the performance of the new apparatus. Two-rotational-states selected AIO(X^2∑+, v=0, N and N+I4) products can be imaged via P(N) and R(N+14) branches of the Av=l band at the same wavelength, during (1+1) resonance-enhanced multi-photon ionization through the AIO(D2E+) intermediate state. In our experiment at 244.145 nm for simultaneous transitions of P(15) and R(29) branch, two rings in slice image were clearly distinguishable, corresponding to the AiO(v=0, N=IS) and AIO(v=0, N=29) states respectively. The energy difference between the two rotational levels is 403 cm^-1. The success of two states resolved in our apparatus suggests a better collisional energy resolution compared with the recent research study [J. Chem. Phys. 140, 214304 (2014)]. 展开更多
关键词 Time-sliced velocity map imaging Crossed beam Laser ablation Metal atom reaction dynamics
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Oxidative stress and hypoxia-induced factor 1α expression in gastric ischemia 被引量:10
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作者 Tao Wang Yu-Fang Leng Yan Zhang Xing Xue Yu-Qing Kang Yue Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第14期1915-1922,共8页
AIM:To investigate the relation of reactive oxygen species (ROS) to hypoxia induced factor 1α (HIF-1α) in gastric ischemia. METHODS:The animal model of gastric ischemia reperfusion was established by placing an elas... AIM:To investigate the relation of reactive oxygen species (ROS) to hypoxia induced factor 1α (HIF-1α) in gastric ischemia. METHODS:The animal model of gastric ischemia reperfusion was established by placing an elastic rubber band on the proximal part of the bilateral lower limb for ligature for 3 h and reperfusion for 0,1,3,6,12 or 24 h. Ischemic post-conditioning,three cycles of 30-s reperfusion and 30-s femoral aortic reocclusion were conducted before reperfusion. Histological and immunohistochemical methods were used to assess the gastric oxidative damage and the expression of HIF1-α in gastric ischemia. The malondialdehyde (MDA) content and superoxide dismutase (SOD),xanthine oxidase (XOD) and myeloperoxidase (MPO) activities were determined by colorimetric assays. RESULTS:Ischemic post-conditioning can reduce post-ischemic oxidative stress and the expression of HIF-1α of gastric tissue resulting from limb ischemia reperfusion injury. MDA,SOD,XOD and MPO were regarded as indexes for mucosal injuries from ROS,and ROS was found to affect the expression of HIF-1α under gastric ischemic conditions. CONCLUSION:ROS affects HIF-1α expression under gastric ischemic conditions induced by limb ischemia reperfusion injury. Therefore,ROS can regulate HIF-1α expression in gastric ischemia. 展开更多
关键词 Oxidative stress Reactive oxygen species HIF-1α expression Gastric ischemia Limb ischemia reperfusion
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DETERMINATION OF IMPURITY ELEMENTS IN ALUMINIUM
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作者 侯小琳 张永保 《Nuclear Science and Techniques》 SCIE CAS CSCD 1994年第4期241-245,共5页
Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling... Twenty five impurity elements in aluminium applied as reactor material are determined. Titanium and nickel are determined with epithermal neutron activation analysis (NAA), magnesium and silicon by inductance coupling plasma emission spectra (ICP), other elements by thermal NAA. The fission coefficient of uraniumis given by an experiment, the interferences of uranium to Ce, Nd, Mo, Zr, La, Sin are subtracted. The detection limits of these methods to all of impurity elements in aluminium are calculated. 展开更多
关键词 Aluminium Impurity element Neutron activation analysis Miniature neutron source reactor Reactor materials
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