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Role of methoxy and C_(α)-based substituents in electrochemical oxidation mechanisms and bond cleavage selectivity of β-O-4 lignin model compounds 被引量:1
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作者 Yang Zhou Qiang Zeng +3 位作者 Hongyan He Kejia Wu Fuqiao Liu Xuehui Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期114-125,共12页
In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl gro... In order to better understand the specific substituent effects on the electrochemical oxidation process of β-O-4 bond, a series of methoxyphenyl type β-O-4 dimer model compounds with different localized methoxyl groups, including 2-(2-methoxyphenoxy)-1-phenylethanone, 2-(2-methoxyphenoxy)-1-phenylethanol, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanone, 2-(2,6-dimethoxyphenoxy)-1-(4-methoxyphenyl)ethanol have been selected and their electrochemical properties have been studied experimentally by cyclic voltammetry, and FT-IR spectroelectrochemistry. Combining with electrolysis products distribution analysis and density functional theory calculations, oxidation mechanisms of all six model dimers have been explored. In particular, a total effect from substituents of both para-methoxy(on the aryl ring closing to Cα) and Cα-OH on the oxidation mechanisms has been clearly observed, showing a significant selectivity on the Cα-Cβbond cleavage induced by electrochemical oxidations. 展开更多
关键词 Lignin model compounds β-O-4 dimers Electrochemical oxidation Oxidation mechanisms substituent effect
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Substituent Effects on 13C NMR and 1H NMR Chemical Shifts of CH=N in Multi-substituted Benzylideneanilines
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作者 曹朝暾 王琳艳 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第1期45-51,I0001,共8页
Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical... Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical shifts (δH(CH=N)) and 13C NMR chemical shifts (δc(CH=N)) of the CH=N bridging group from di-substituted to multi-substituted XBAYs was made based on a total of 182 samples of XBAYs, together with the NMR data of other 129 samples of di-substituted XBAYs quoted from literatures. The results show thatthe substituent specific cross-interaction effect parameter (△(∑σ)2) plays an important role in quantifying the δc(CH=N) values of XBAYs, but it is negligible for quantifying the δH (CH=N) values; the other substituent parameters also present different influences on the δc (CH=N) and (δH (CH=N). On the whole, the contributions of X and Y to the δc (CH=N) of XBAYs are balanced, but the δH(CH=N) values of XBAYs mainly rely on the contributions of X. 展开更多
关键词 Multi-substituted benzylideneanilines substituent effects 1H NMR chemicalshifts 13C NMR chemical shifts substituent specific cross-interaction effect
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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting Activity Therapeutic effects
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Substituent Effects on Reduction Potentials of Meta-substituted and Para-substituted Benzylideneanilines 被引量:1
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作者 王琳艳 曹朝暾 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第2期260-264,I0002,共6页
Effects of meta-substituent of 3,4'/4,3'/3,3'-substituted benzylideneanilines (XBAYs) on the electrochemical reduction potentials (E(Red)) were investigated, in which 49 samples of target compounds were synth... Effects of meta-substituent of 3,4'/4,3'/3,3'-substituted benzylideneanilines (XBAYs) on the electrochemical reduction potentials (E(Red)) were investigated, in which 49 samples of target compounds were synthesized, and their reduction potentials were measured by cyclic voltammetry. The substituent effects on the E(Red) of target compounds were analyzed and an optimality equation with four parameters (Hammett constant a of X, Hammett constant a of Y, excited-state substituent constant σexCC of X, and the substituent specific cross-interaction effect △σexCC2 between X and Y) was obtained. The results show that the factors affecting the E(Red) of 3,4'/4,31/3,3P-substituted XBAYs are different from those of 4,4'-substituted XBAYs. For 3,4'/4,3'/3,3'-substituted XBAYs, σ(X) and σ(Y) must be employed, and the contribution of △σexCC2 is important and not negligible. Compared with 4,4'-substituted XBAYs, X group contributes less to 3,4'/4,3'/3,3'-substituted XBAYs, while Y group contributes more to them. Additionally, it was observed that either para-substituted XBAYs or meta-substituted XBAYs, the substituent effects of X are larger than those of Y on the E(Red) of substituted XBAYs. 展开更多
关键词 3 4r/4 3'/3 3'-substituted benzylideneanilines substituent effects Electro-chemical reduction potentials Cyclic voltammetry Excited-state substituent constant
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Theoretical Studies on the Aminolysis of Ester: Effects of the Catalysis and Substituent to the Reaction of Methyl Indole-3-acetate with Ammonia 被引量:1
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作者 ZHANG Liang CHEN Rong LIANG Guo-Ming 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期855-866,共12页
A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p)... A comprehensive exploration of the aminolysis mechanism for methyl indole-3-acetate with ammonia is carried out by employing the B3 LYP/6-311++G(d,p), M06-2 X/6-311++G(d,p) and MP2/6-311++G(d,p)//M06-2 X/6-311++G(d,p) levels. Two alterative reaction channels of the concerted and addition/elimination stepwise processes including the uncatalyzed, base-catalyzed reactions are taken into consideration. Subsequently, the substituent effects and solvent effects in methanol are also evaluated at the M06-2 X/6-311++G(d,p) level. The calculated results indicate that the calculated values of M06-2 X level are quite close to those of MP2, the stepwise pathway has more advantages to the concerted one for all of the reaction processes and the catalyst facilitates the proton migration and decreases the energy barriers as well. It is shown that the most preferred mechanism is the based-catalyzed stepwise process, the substituent of NH2 group slightly accelerates all the aminolysis reaction processes, and the solvent effect does not remarkably change the mechanism of the reaction. 展开更多
关键词 AMINOLYsIs METHYL indole-3-acetate mechanism catalytic effect substituent effect
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POLAR SUBSTITUENT EFFECTS OF ORGANOPHOSPHORUS ESTERS IN STRUCTURE-REACTIVITY STUDIES 被引量:1
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作者 Wen Xiang HU Cheng Ye YUAN Shu Sen LI Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032 Institute of Pharmacology and Toxicology,Academy of Military Medical Sciences,Beijing 100850. 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期579-582,共4页
In order to study the polar substituent effect almost with no steric effect in organophosphorus chemistry,a series of 4-substituted-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxides(1)and p-substituted phenylphospho... In order to study the polar substituent effect almost with no steric effect in organophosphorus chemistry,a series of 4-substituted-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane 1-oxides(1)and p-substituted phenylphosphonates(2)and corresponding mono hexyl esters(3)as model were synthesized.^(31)P-NMR chemical shifts of compounds(1)in methanol and deuterioacetone were determined.The Δδ values reflect 4-sbstituent po- lar effect.The ^(31)P-NMR of compounds(2)and(3)and the pKa of compounds(3)were also measured.The results showed that the trend of polar effects of substituents in both carboxylic and organophosphates chemistry are similar,and the change of polar effects in variation with the alkyl groups is not significant. 展开更多
关键词 MNDO POLAR substituent effects OF ORGANOPHOsPHORUs EsTERs IN sTRUCTURE-REACTIVITY sTUDIEs
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Effects of Pressure, Solvent, and Substituent on the Thermal Isomerization of 2-Oxo- spiro[diazirine-3,3'-indoline]
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作者 Yoshimi Sueishi Genta Okazaki 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2001年第1期95-101,共7页
The kinetic effects of pressure, solvent, and substituent on the thermal isomerization from 2 oxospiro[diazirine 3,3 indoline] to 3 diazo 2 oxo indoline have been examined. The rate constants of the thermal is... The kinetic effects of pressure, solvent, and substituent on the thermal isomerization from 2 oxospiro[diazirine 3,3 indoline] to 3 diazo 2 oxo indoline have been examined. The rate constants of the thermal isomerization increased with increasing external pressure and were related to the σ + P substituent constant of Hammett correlation. The results suggest that the thermal isomerization proceeds via a dipolar transition state involving heterolytic bond fission. However, the kinetic solvent effects on the thermal isomerization were not observed. The special solvent effects were discussed on the basis of the linear free energy relationship. 展开更多
关键词 Kinetic study Pressure effect substituent effect Thermal isomerization DIAZIRINE
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Theoretical Study of Impact of Side Substituent Effecton Intramolecular Proton Transfer of Perylenequinone
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作者 Ying QIAN Yan WANG Ruo Zhuang LIU(Department of Chemical and Environmental Engineering, Beijing Polytechnic University, Beliing100022)(Department of Chemistry, Beijing Normal University, Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第4期317-320,共4页
Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the peryle... Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the perylenequinone molecule is of stable structure. and all substituents may cause the decrease of barriers for the hydrogen transfer reaction. 展开更多
关键词 perylenequinone AM1 method proton transfer substituent effect
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Theoretical Studies on Substituent Effect of the Reaction of Amide and Formaldehyde
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作者 LAI Wel-peng LIAN Peng +3 位作者 QIU Shao-jun GE Zhong-xue WANG Bo-zhou XUE Yong-qiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第6期1007-1010,共4页
The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYP method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH(CH3)2,CH2CH(CH3)2,CH(CH3)CH2CH3 and ... The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYP method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH(CH3)2,CH2CH(CH3)2,CH(CH3)CH2CH3 and C(CH3)3.Based on the optimization of the structures for reactants and products,the thermodynamic functions of all the species for an actual state were obtained.The thermodynamic data and the equilibrium constants were investigated within a temperature range of 300―343.15 K.The calculated results show that the reaction is exothermic and spontaneous.The trends of all thermodynamic properties are consistent with the temperature.The preferential order of the substituent effect is CH2CH(CH3)2CH(CH3)CH2CH3CH2CH2CH2CH3 CH2CH2CH3CH2CH3≈CH(CH3)2C(CH3)3≈CH3. 展开更多
关键词 1 3 5-Trinitro-1 3 5-triazacyclohexane(RDX) substituent effect THERMODYNAMICs
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Substituent Effects on the Hydrogen Bonding Between Phenolate and HF, H_2O and NH_3
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作者 FANG Ying LIU Lei GUO Qing xiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期348-353,共6页
B3LYP/6 31+g( d ) calculations were performed on the hydrogen bonded complexes between substituted phenolates and HF, H 2O as well as NH 3. It was found that some properties of the non covalent complexes, inclu... B3LYP/6 31+g( d ) calculations were performed on the hydrogen bonded complexes between substituted phenolates and HF, H 2O as well as NH 3. It was found that some properties of the non covalent complexes, including the interaction energies, donor acceptor (host guest) distances, bond lengths, and vibration frequencies, could show well defined substituent effects. Thus, from the substituent studies we can not only understand the mechanism of a particular non covalent interaction better, but also easily predict the interaction energies and structures of a particular non covalent complex, which might otherwise be very hard or resource consuming to be known. This means that substituent effect is indeed a useful tool to be used in supramolecular chemistry and therefore, many valuable studies remain to be carried out. 展开更多
关键词 Noncovalent interaction Hydrogen bonding substituent effect Density function theory
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ELECTRONIC EFFECTS OF POLYFLUORINATED SUBSTITUENTS ON THE POLYMERIZATION AND THE PROPERTIES OF POLYTHIOPHENES
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作者 张旭庆 沈学明 +2 位作者 杨士勇 陆伟 张景云 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第1期15-23,共9页
Three series of polythiophenes containing fluoroalkoxy and fluoroether substituents were prepared by electrochemical polymerization. The effect of substituents with fluoroalkoxy or ether functional groups on the elect... Three series of polythiophenes containing fluoroalkoxy and fluoroether substituents were prepared by electrochemical polymerization. The effect of substituents with fluoroalkoxy or ether functional groups on the electrochemical polymerization of thiophene monomers and properties of the obtained polymers were analyzed. The introduction of a fluoroether functional group at the 3-position of the thiophene ring leads to an increase of the oxidation potential of the monomer and to a decrease of the conductivity of the resulting polymers, even with the use of a CH2 group as spacer. Conversely, the presence of an oxygen atom directly at the 3-position of the thiophene ring, which offsets the negative withdrawing effect of fluoroalkyl groups, facilitates the synthesis of highly conducting polythiophenes. 展开更多
关键词 electronic effect electrochemical polymerization polythiophene polyfluorinated substituent
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Substituent Effect on Mercury-199 Chemical Shifts in Some Bisarylmercurials and Aryl(2-benzothiazolylthio) mercurials
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作者 YANG Li, CHEN Ji-hong and LEI Xue-gong (National Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, 730000)WU Yang-jie and SONG Mao-ping (Department of Chemistry, Zhengzhou University, Zhengzhou, 450052) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第2期81-83,共3页
The present paper covers the 199 Hg NMR chemical shifts of 24 substituted diphenylmercurials and phenyl(2-benzothiazolylthio)mercurials. There is a good linear relationship between the chemical shift and the Hammett c... The present paper covers the 199 Hg NMR chemical shifts of 24 substituted diphenylmercurials and phenyl(2-benzothiazolylthio)mercurials. There is a good linear relationship between the chemical shift and the Hammett constant of the substituents for both series of compounds, and electron donating substituents cause the chemical shift towards downfield. 展开更多
关键词 199Hg chemical shift substituent effect Bisarylmercurial Aryl arylthio mercury
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Substituent Effect on Infrared Spectra and Thermodynamic Properties of Polynitroamino Substituted Cyclopentane and Cyclohexane
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作者 Ling Qiu Xue-dong Gong He-ming Xiao 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第6期526-534,共9页
Density functional theory method was employed to study the effect of the nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct polycyclic or caged nitramines. Based on the optimize... Density functional theory method was employed to study the effect of the nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct polycyclic or caged nitramines. Based on the optimized molecular structures of two groups of monocyclic nitramines at the B3LYP/6-31G^** level, the infrared (IR) spectra were obtained and assigned by harmonic vibrational analysis. The calculated results agree reasonably with the available experimental data. According to the principles of statistic thermodynamics, thermodynamic properties were derived from the IR spectra, which were linearly correlated with the number of nitroamino groups as well as the temperature. The contributions of nitroamino groups to thermodynamic properties are in accord with the group additivity. 展开更多
关键词 Density functional theory substituent effect Monocyclic nitramine Infrared spectrum Thermodynamic property
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SYNTHESES AND SUBSTITUENT EFFECTS ON 4-^(13)C-NMR OF BIOACTIVE 4-SUBSTITUTED-2,6,7-TRIOXA-1-PHOSPHABICYCLO[2.2.2]OCTANE-1-OXIDES
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作者 Wen Xiang HU Liu Hong YUN Institute of Pharmacology and Toxicology,Academy of Military Medical Sciences,Beijing 100850 Ji Sheng CHEN Hua Tang XU Shui Sheng JIA Xuan Long XU Beijing Institute of Pharmaceutical Chemistry,No.401,Po Box 1044,Beijing 102205 Cheng Ye YUAN Shu Sen LI Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期959-962,共4页
Ten 4-substituted bicyclic phosphates were synthesized and their ^(13)C-NMR were also determined.A good relationship was observed between 4-^(13)C chemical shift and Taft σ_X induc- tive paramenters.Substituent effec... Ten 4-substituted bicyclic phosphates were synthesized and their ^(13)C-NMR were also determined.A good relationship was observed between 4-^(13)C chemical shift and Taft σ_X induc- tive paramenters.Substituent effects on ~3J_(P-C) coupling constant were studied. 展开更多
关键词 NMR sYNTHEsEs AND substituent effects ON 4 C-NMR OF BIOACTIVE 4-substituTED-2 6 7-TRIOXA-1-PHOsPHABICYCLO[2.2.2]OCTANE-1-OXIDEs
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甘肃积石山 M_(s)6.2级地震的震害特征与启示 被引量:5
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作者 王丽丽 王兰民 +5 位作者 卢育霞 许世阳 夏晓雨 盖海龙 池佩红 郭梅 《世界地震工程》 北大核心 2024年第1期58-71,共14页
2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特... 2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特点进行了统计分析;从抗震设计与施工管理、场地放大效应与地震次生灾害对建筑结构抗震性能的影响等角度,提出了此次地震的震害启示。结果表明:1)严重破坏和毁坏的建筑结构主要集中在老旧的土木结构、砖木结构和无设防或设防不规范的砖混结构。2)造成建筑结构破坏的主要原因是少量自建房抗震设计和施工的不规范、场地放大效应和地震次生灾害。3)优化和改良生土砌筑材料,改进纵横墙间的拉结措施,强化结构整体性是提高土木结构抗震的有效方法;普及“上下圈梁与构造柱”等基本抗震设防措施,规范水泥砂浆强度,提升农村工匠的施工水平,可有效提高砌体结构的整体性,避免房屋出现整体性垮塌;室内洗手间的墙体应该与房顶、纵横墙间建立有效联接,提高结构的抗震性能。4)孤突斜坡、河流高阶地与岸边为抗震不利地带。当建造用地极为匮乏,不得不选址在这些场地之上时,应该综合考虑场地的地形地貌特征、岩土体物理力学特性、水文地质条件、抗震设防目标、建筑结构类型等影响因素,做好地震灾害风险评估,根据评估结果进行科学设防。灾后重建过程中,应由政府统一规划选址、统一设计,规范施工。 展开更多
关键词 积石山6.2级地震 震害调查 场地放大效应 黄土液化流滑 震害特征
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SUBSTITUENT EFFECTS IN THE BIRCH REDUCTION REACTION OF SUBSTITUTED BENZENES
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作者 张雅文 沈宗旋 《苏州大学学报(自然科学版)》 CAS 1994年第2期165-173,共9页
The substituent effects in the Birch reduction reaction of substituted benzenes are discussed. Anonplanar, boat-form conformation is suggested for the benzene radical anion formed by the transfer of an electron to a s... The substituent effects in the Birch reduction reaction of substituted benzenes are discussed. Anonplanar, boat-form conformation is suggested for the benzene radical anion formed by the transfer of an electron to a substituted benzene molecule. In this conformation ,the 1,4-dienyl radical anion has two double bonds isolated, the negative charge is localized on posion 6 and the single electron is on position 3, the farthest position from the negative chareg, when the substituent is electron-withdrawing. Both alkyl and alkoxy groups are considered to be electron-withdrawing. These substituents should be activating groups for their inductive effect. The reaction rate decreasing of alkyl benzenes may be cansed by reasons other than electronic effect. The reduction of benzoic acid and benzamide, in which 1,4-dihydro benzenes are obtained, is considered to be an exceptional example, in which an extra stabilized Y-aromatic radical anion may be invilved. 展开更多
关键词 甲苯 取代反应 芳香族化合物 不饱和化合物
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Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer’s disease 被引量:6
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作者 Lin Wang Bi-Qiang Zhou +5 位作者 Ying-Hong Li Qian-Qian Jiang Wei-Hong Cong Ke-Ji Chen Xiao-Min Wen Zheng-Zhi Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期226-232,共7页
Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.How... Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.However,its low bioavailability and adverse reactions with conventional administration limit its clinical application.In this study,we prepared berberine nanoliposomes using liposomes characterized by low toxicity,high entrapment efficiency,and biodegradability,and modified them with lactoferrin.Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency.We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer’s disease established by injection of amyloid-beta 1-42 into the lateral ventricle.Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus,reduced tau over-phosphorylation in the cerebral cortex,and improved mouse behavior.These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer’s disease. 展开更多
关键词 ACETYLCHOLINEsTERAsE Alzheimer’s disease apoptosis BERBERINE brain targeting LACTOFERRIN NANOLIPOsOMEs neuroprotective effects Tau phosphorylation
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law effective medium theory stress threshold determination
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Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结的构筑及其光解水产氢性能研究 被引量:3
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作者 于佳慧 姚欣彤 +4 位作者 苏萍 王仕凯 张大凤 葛博 蒲锡鹏 《聊城大学学报(自然科学版)》 2024年第1期52-61,共10页
采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理... 采用超声辅助研磨煅烧法制备了Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S S型异质结光催化剂,通过X射线粉末衍射仪、扫描电子显微镜、X射线光电子能谱、固体紫外漫反射等测试技术表征了样品的物相、形貌、化学元素组成以及光吸收能力等物理化学性质。在可见光加近红外光照射下进行了光催化析氢性能测试,结果表明,Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S复合材料的光解水产氢性能均优于纯相的Mn_(0.3)Cd_(0.7)S和Cu_(3)Mo_(2)O_(9),其中Cu 3Mo 2O 9的质量分数为1%的Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S显示出最佳的产氢速率(1.554 mmol·h^(-1)·g^(-1)),是Mn 0.3 Cd_(0.7)S的5.5倍。且经过四次循环实验后仍保持较好的光催化活性。此外,根据电化学测试以及红外热成像结果提出了合理的机理,Cu 3Mo 2O 9的光热效应与S型异质结的协同作用是Cu_(3)Mo_(2)O_(9)/Mn_(0.3)Cd_(0.7)S光催化活性提高的关键。 展开更多
关键词 光解水产氢 s型异质结 Mn_(0.3)Cd_(0.7)s Cu_(3)Mo_(2)O_(9) 光热效应
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Effect of Hashimoto’s Thyroiditis on Efficacy of 131I Ablation Therapy in Intermediate- and High-Risk of Thyroid Papillary Carcinoma
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作者 Lu Zhou Gang Cheng 《Journal of Biosciences and Medicines》 2023年第4期103-113,共11页
Objective: The purpose of this study was to investigate the effect of Hashimoto’s thyroiditis on efficacy of <sup>131</sup>I ablation in intermediate- and high-risk of thyroid papillary carcinoma patients... Objective: The purpose of this study was to investigate the effect of Hashimoto’s thyroiditis on efficacy of <sup>131</sup>I ablation in intermediate- and high-risk of thyroid papillary carcinoma patients. The findings will help to develop a personalized treatment plan for patients with thyroid papillary carcinoma complicated with Hashimoto’s thyroiditis. Material and Methods: From January 2016 to December 2020, patients who were diagnosed with intermediate- and high-risk PTC with lymph node metastasis were analyzed retrospectively, excluding patients with incomplete clinical data, distant metastasis, positive TGAb, TSH Results: A total of 525 patients (166 males and 359 females) were included in the study, including 368 patients in ER group (70.1%) and 157 patients in NER group (29.9%). Eleven factors including combining Hashimoto’s thyroiditis, pre-ablative Tg levels, sex, tumor diameter, extraglandular invasion, multifocal, bilateral lesions, central lymph node metastasis, lateral lymph node metastasis, lymph node metastasis rate, thyroglobulin were statistically different between ER group and NER group with significance at P Conclusion: Hashimoto’s thyroiditis, Ps-Tg level and lateral lymph node metastasis are potential predictors for short-term efficacy of <sup>131</sup>I treatment in intermediate- and high-risk thyroid papillary carcinoma. Hashimoto’s thyroiditis, high Ps-Tg level and increased number of lateral lymph node metastasis reduce the efficacy of <sup>131</sup>I therapy in patients with intermediate and high risk thyroid papillary carcinoma. 展开更多
关键词 Papillary Thyroid Carcinoma Hashimoto’s Thyroiditis <sup>131sup>I Therapy Curative effect
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