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A Note on the Property of ψ-Function 被引量:2
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作者 XIE Zitian ZHOU Qinghua 《Wuhan University Journal of Natural Sciences》 CAS 2011年第2期139-142,共4页
About the accurate value of ψ ( x ) = Γ′ ( x ) / Γ ( x), we know only ψ (1)and ψ (1/ 2).In this paper, by calculating the accurate values of some series expansion of a function and applying some skills... About the accurate value of ψ ( x ) = Γ′ ( x ) / Γ ( x), we know only ψ (1)and ψ (1/ 2).In this paper, by calculating the accurate values of some series expansion of a function and applying some skills of complex analysis, we prove that the expression of the ψ-function admits a finite expression in elementary function for rational number z. As an application, some examples are given. 展开更多
关键词 ψ-function γ-function Euler’s constant
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A New Alpha-function for the Peng-Robinson Equation of State: Application to Natural Gas 被引量:3
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作者 Hamid Saffari Alireza Zahedi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第10期1155-1161,共7页
Cubic equations of state(EOSs) are simple and easy at calculation. One way of improving the accuracy of a cubic EOS is through the modification of temperature-dependent energy parameter by using alpha-function.The ind... Cubic equations of state(EOSs) are simple and easy at calculation. One way of improving the accuracy of a cubic EOS is through the modification of temperature-dependent energy parameter by using alpha-function.The industrial applications of natural gas are very wide and as a result, prediction of thermodynamic properties and phase behavior of natural gas is an important part of design for such processes. In this work we develop a newα-function for the Peng-Robinson(PR) EOS with the parameters optimized especially for natural gas components.The parameters are generalized as a linear function of acentric factor. The results are compared to the predictions from original PR EOS and other α-functions in literature. It is shown that the new α-function presents a good accuracy with the average deviation of 1.42% for natural gas components. 展开更多
关键词 Peng-Robinson equation of state natural gas α-function
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Azulenoisoindigo: A building block for π-functional materials with reversible redox behavior and proton responsiveness 被引量:1
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作者 Bin Hou Jing Li +4 位作者 Xiaodi Yang Jianwei Zhang Hanshen Xin Congwu Ge Xike Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第4期2147-2150,共4页
Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo(Az II), an azulene-based isoindigo anal... Azulene, one of representative nonbenzenoid aromatic hydrocarbons, exhibits unique molecular structure and distinctive physical and chemical properties. Herein, azulenoisoindigo(Az II), an azulene-based isoindigo analogue, is designed and synthesized, which has a twisted molecular backbone and R/Sisomers in single crystals. Interestingly, Az II shows the characteristics of both isoindigo and azulene,such as reversible redox behavior and reversible proton responsiveness. UV-vis-NIR,^(1)H NMR and electron paramagnetic resonance(EPR) measurements were carried out to get insights into the possible mechanism of the proton-responsive property of Az II. The results demonstrated that only one azulenyl moiety of molecule of Az II was protonated and deprotonated, and the protonated Az II can be further oxidized to form azulenium cation radicals. 展开更多
关键词 AZULENE Nonbenzenoid aromatic hydrocarbons Isoindigo π-functional materials Proton responsiveness
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Adsorptive removal of tetracycline from water using Fe(Ⅲ)-functionalized carbonized humic acid 被引量:1
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作者 Dairui Xie Hongcheng Zhang +4 位作者 Meng Jiang Hao Huang Heng Zhang Yang Liao Shilin Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第10期2689-2698,共10页
Humic acid(HA)was carbonized at 300,400 and 500℃ and then functionalized with 1 wt%–12 wt%Fe(Ⅲ)respectively[CHA300/400/500-Fe(Ⅲ)].Adsorption of such Fe(III)-functionalized carbonized HA as adsorbents to aqueous te... Humic acid(HA)was carbonized at 300,400 and 500℃ and then functionalized with 1 wt%–12 wt%Fe(Ⅲ)respectively[CHA300/400/500-Fe(Ⅲ)].Adsorption of such Fe(III)-functionalized carbonized HA as adsorbents to aqueous tetracycline(TC:25 mg·L^-1)was studied.The adsorption equilibrium time for CHA400-Fe(Ⅲ)to TC was 6 h faster and the adsorption removal efficiency(Re)was two times higher than that of HA/CHA.The adsorption Reof CHA400-Fe(Ⅲ)loaded 10%iron[CHA400-(10%)Fe(Ⅲ)]to TC could reach 99.8%at 8 h and still kept80.6%after 8 cycles.The adsorption kinetics were well fitted to the pseudo-second-order equation and the adsorption isotherms could be well delineated via Langmuir equations(R^2N 0.99),indicating that the homogeneous chemical adsorption of TC occurred on the adsorbents.The main adsorption mechanisms of TC were complexation Fe(III)and hydrophobic distribution.Electropositive and electronegative repulsion between TC and CHA400-(10%)Fe(Ⅲ)at lowly p H(2)and highly p H(8–10)respectively,leaded to the relatively low adsorption capacity and more notable influence of ion concentration.When the p H was between 4 and 8,TC mainly existed in neutral molecules(TCH2),so the influence of ion concentration was not obvious.The dynamic adsorption results showed that the CHA400-(10%)Fe(Ⅲ)could continuously treat about 2.4 L TC(27 mg·L^-1)wastewater with the effluent concentration as low as 0.068 mg·L^-1.Our study suggested a broad application prospect of a new,effective,lowcost and environment-friendly adsorbent CHA400-(10%)Fe(Ⅲ)for treatment of low-concentration TC polluted wastewater. 展开更多
关键词 Fe(Ⅲ)-functionalized carbonized humic acid Composites ADSORPTION Low-concentration tetracycline Waste water
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Initial Oxidation of γ-TiAl(111) Surface:Density-functional Theory Study
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作者 Hong Li Shaoqing Wang Hengqiang Ye 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第4期569-576,共8页
In this paper, we reported a first-principles investigation on the structural and electronic properties of O adsorption on the γ-TiAI(111) surface, to illustrate the oxidation process. It has been found that: (1... In this paper, we reported a first-principles investigation on the structural and electronic properties of O adsorption on the γ-TiAI(111) surface, to illustrate the oxidation process. It has been found that: (1) rather than stopping with one full monolayer of coverage, oxygen adsorption continues till two monolayer coverage, rendering an oxide-like structure; (2) full structural relaxation makes the surface oxide layer denser and more stable, which hinders the subsequent O adsorption (oxidation) process. In addition, the transformation from metal to oxide surface was identified by analyzing the local density of states through the oxidation steps, which was in good agreement with experimental results. 展开更多
关键词 Density-functional theory Γ-TIAL SURFACE OXIDATION
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Comparative study of the adsorption performance of NH_(2)-functionalized metal organic frameworks with activated carbon composites for the treatment of phenolic wastewaters
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作者 Bolong Jiang Shunjie Shi +3 位作者 Yanyan Cui Jiayou Li Nan Jiang Yanguang Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期130-139,共10页
To better understand the role of the-NH_(2)group in adsorption process of phenolic wastewaters,NH_(2)-functionalized MIL-53(Al)composites with activated carbon(NH_(2)-M(Al)@(B)AC)were prepared.The results showed that ... To better understand the role of the-NH_(2)group in adsorption process of phenolic wastewaters,NH_(2)-functionalized MIL-53(Al)composites with activated carbon(NH_(2)-M(Al)@(B)AC)were prepared.The results showed that the-NH_(2)group could increase the mesopore volume for composites,which promotes mass transfer and full utilization of active sites,because hierarchical mesopore structure makes the adsorbent easier to enter the internal adsorption sites.Furthermore,the introduction of the-NH_(2)group can improve the adsorption capacity,decrease the activation energy,and enhance the interaction between the adsorbent and p-nitrophenol,demonstrating that the-NH_(2)group plays a crucial role in the adsorption of p-nitrophenol.The density functional theory calculation results show that the H-bond interaction between the-NH_(2)group in the adsorbent and the-NO_(2)in the p-nitrophenol(adsorption energy of -35.5 kJ·mol^(-1)),and base-acid interaction between the primary-NH_(2)group in the adsorbent and the acidic-OH group in the p-nitrophenol(adsorption energy of -27.3 kJ·mol^(-1))are predominant mechanisms for adsorption in terms of the NH_(2)-functionalized adsorbent.Both NH_(2)-functionalized M(Al)@AC and M(Al)@BAC composites exhibited higher p-nitrophenol adsorption capacity than corresponding nonfunctionalized composites.Among the composites,the NH_(2)-M(Al)@BAC had the highest p-nitrophenol adsorption capacity of 474 mg·g^(-1). 展开更多
关键词 NH_(2)-functionalized adsorbent Phenolic wastewaters ADSORPTION Mechanism Density functional theory
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The Symmetry of Riemann <i>ξ</i>-Function
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作者 Chuanmiao Chen 《Advances in Pure Mathematics》 2020年第8期464-470,共7页
To prove RH, studying <span style="white-space:nowrap;">ζ and using pure analysis method likely are two kinds of the incorrect guide. Actually, a unique hope may study Riemann function <img src=&qu... To prove RH, studying <span style="white-space:nowrap;">ζ and using pure analysis method likely are two kinds of the incorrect guide. Actually, a unique hope may study Riemann function <img src="Edit_b4e53620-7ae2-4a2b-aee0-351c62aef8cd.png" width="250" height="20" alt="" /> by geometric analysis, which has the symmetry: <span style="white-space:nowrap;">v = 0 if <span style="white-space:nowrap;">β = 0, and <img src="Edit_8c67c5d7-c1d4-4cad-8792-78e4bd172ebd.png" width="150" height="28" alt="" /> Assume that |u| is single peak in each root-interval <img src="Edit_a91df253-2965-4b03-8033-54aba2e23036.png" width="85" height="27" alt="" /> of u for any fixed <span style="white-space:nowrap;">β <span style="white-space:nowrap;">∈ (0,1/2], using the slope u<sub>t </sub>of the single peak, we prove that v has opposite signs at two end-points of I<sub>j</sub>, there surely is an inner point so that v = 0, so {|u|,|v|/<span style="white-space:nowrap;">β}form a local peak-valley structure, and have positive lower bound <img src="Edit_04798c0f-8e21-4a3a-ae12-0e28b01ee348.png" width="167" height="22" alt="" />in I<sub>j</sub>. Because each t must lie in some <em style="white-space:normal;">I<sub style="white-space:normal;">j</sub> , then ||<span style="white-space:nowrap;">ξ|| > 0 is valid for any t. In this way, the summation process of <span style="white-space:nowrap;">ξ is avoided. We have proved the main theorem: Assume that u (t, <span style="white-space:nowrap;">β) is single peak, then RH is valid for any <img src="Edit_ed8521a3-63b1-417f-a3b0-a3c790bae519.png" width="140" height="19" alt="" />. If using the equivalence of Lagarias (1999), the assumption of single peak can be canceled. Therefore our new thinking is that we have found the local peak-valley structure of <span style="white-space:nowrap;">ξ, which may be the geometry structure expected by Bombieri (2000), and proposed a basic framework of proving RH by geometric analysis. 展开更多
关键词 Riemann ξ-function SYMMETRY Peak-Valley Structure Single Peak RH
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GENERALIZED FRACTIONAL CALCULUS OF THE ALEPH-FUNCTION INVOLVING A GENERAL CLASS OF POLYNOMIALS
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作者 R.K.SAXENA D.KUMAR 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1095-1110,共16页
The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-fun... The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-function, Appell function F3 and a general class of poly- nomials. The results obtained provide unification and extension of the results given by Saxena et al. [13], Srivastava and Grag [17], Srivastava et al. [20], and etc. The results are obtained in compact form and are useful in preparing some tables of operators of fractional calculus. On account of the general nature of the Saigo-Maeda operators, R-function, and a general class of polynomials a large number of new and known results involving Saigo fractional calculus operators and several special functions notably H-function, /-function, Mittag-Leffier function, generalized Wright hypergeometric function, generalized Bessel-Maitland function follow as special cases of our main findings. 展开更多
关键词 generalized fractional calculus operators a general class of polynomials R-function H-function /-function generalized Wright hypergeometric function Mittag-Leffler function generalized Bessel-Maitland function
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AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS
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作者 Safoura Rezaei ADERYANI Azam AHADI +1 位作者 Reza SAADATI Hari M.SRIVASTAVA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期311-338,共28页
In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better... In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem. 展开更多
关键词 permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality
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关于Euler gamma函数Γ与一类L-函数的代数微分无关性
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作者 李效敏 李奕萱 《中国海洋大学学报(自然科学版)》 北大核心 2025年第S1期106-109,148,共5页
本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了... 本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了陈玮和王琼2021年的相应结果。 展开更多
关键词 Euler gamma函数Γ L-函数类S 微分无关性 代数微分方程
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月见草全长转录组测序及γ-亚麻酸代谢相关基因鉴定
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作者 陈岳 佘为为 +3 位作者 姚丹青 徐俐琴 徐菲 张微微 《福建农业学报》 北大核心 2025年第6期585-593,共9页
【目的】月见草(Oenothera biennis)富含类脂肪酸、黄酮、酚类等多种生物活性成分,具有重要的药用价值。利用全长转录组测序可为月见草关键代谢产物的合成研究提供理论依据。【方法】以月见草根、茎、叶片、花和种子5个部位为样品,利用... 【目的】月见草(Oenothera biennis)富含类脂肪酸、黄酮、酚类等多种生物活性成分,具有重要的药用价值。利用全长转录组测序可为月见草关键代谢产物的合成研究提供理论依据。【方法】以月见草根、茎、叶片、花和种子5个部位为样品,利用单分子实时测序(single-molecule real-time,SMRT)技术进行全长转录组测序,并通过同源比对在转录组数据中鉴定与γ-亚麻酸代谢相关的基因。【结果】测序结果去冗余后共获得28875个unigenes,平均长度1718 bp,GC含量45.63%。NR数据库比对发现,月见草与石榴(Punica granatum)的相似度最高。GO注释中18169个unigenes分为生物学过程、细胞组成和分子功能三大类。此外,12213个unigenes被注释到KEGG数据库的5大类群,其中代谢通路富集的基因最多,共5416个。转录因子分析显示,6695条序列分别属于56个转录因子家族。简单重复序列(simple sequence repeat,SSR)分析表明,单核苷酸重复和三核苷酸重复数目最多,分别是5543和5529个。SSR标记的多态性结果显示,13对SSR引物在6种月见草中存在多态性。此外,在月见草转录组库中共鉴定了50个γ-亚麻酸代谢相关基因,其中20个基因在种子中表达量较高。【结论】本研究获得了月见草的全长转录组数据库,为后续对月见草进行基因克隆和功能研究提供了数据支撑和基因资源。 展开更多
关键词 月见草 全长转录组 测序分析 功能注释 Γ-亚麻酸
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口腔扁平苔藓患者血清HSP70、IFN-γ水平与病情程度及免疫功能的关系 被引量:1
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作者 胡伟 殷娟娟 冯良 《四川医学》 2025年第6期664-669,共6页
目的探讨口腔扁平苔藓(OLP)患者血清热休克蛋白70(HSP70)、干扰素γ(IFN-γ)水平与病情程度及免疫功能的关系。方法选取2021年3月至2023年1月于我院进行治疗的116例OLP患者,根据OLP溃疡分型判断标准将患者分为溃疡组48例和非溃疡组68例... 目的探讨口腔扁平苔藓(OLP)患者血清热休克蛋白70(HSP70)、干扰素γ(IFN-γ)水平与病情程度及免疫功能的关系。方法选取2021年3月至2023年1月于我院进行治疗的116例OLP患者,根据OLP溃疡分型判断标准将患者分为溃疡组48例和非溃疡组68例,另选取研究期间来我院体检的60例健康志愿者为对照组。酶联免疫吸附法检测血清HSP70、IFN-γ水平及炎性相关因子水平;流式细胞仪检测全血中淋巴细胞亚群水平;免疫散射比浊法检测血清中免疫球蛋白IgA、IgG、IgM水平;采用Pearson相关性分析血清HSP70、IFN-γ水平与溃疡组OLP患者炎性指标及免疫功能指标的相关性;ROC曲线分析血清HSP70、IFN-γ评估OLP患者发生溃疡的价值。结果溃疡组和非溃疡组血清HSP70、IFN-γ、IL-6、IL-17水平均高于对照组,且溃疡组高于非溃疡组(P<0.05);而IL-4水平低于对照组,且溃疡组低于非溃疡组(P<0.05)。溃疡组和非溃疡组免疫相关指标CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)、IgA、IgG水平均低于对照组,CD19^(+)、CD8^(+)及IgM水平均高于对照组(P<0.05),且溃疡组和非溃疡组患者的CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)、CD19^(+)、CD8^(+)及IgM水平比较,差异均有统计学意义(P<0.05),而IgA、IgG水平差异无统计学意义(P>0.05)。Pearson相关分析结果表明,溃疡组OLP患者HSP70、IFN-γ水平与IL-4、CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)均呈负相关,与IL-6、IL-17、CD8^(+)、CD19^(+)、IgM水平均呈正相关(P<0.05),与IgA、IgG、CD16^(+)56无相关性(P>0.05)。ROC曲线显示,HSP70对溃疡预测的AUC为0.706,IFN-γ对溃疡预测的AUC为0.848,二者联合对溃疡预测的AUC为0.915,明显高于二者单独预测,(Z_(联合vs.HSP70)=2.860、P=0.004;Z_(联合vs.IFN-γ)=2.244、P=0.025)。结论OLP患者血清HSP70、IFN-γ水平表达异常升高,可反映OLP患者的病情程度,且血清HSP70、IFN-γ水平与OLP患者的免疫功能密切相关。 展开更多
关键词 口腔扁平苔藓 溃疡 热休克蛋白70 干扰素Γ 病情程度 免疫功能
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腹部推拿通过激素组学与γ-氨基丁酸能系统协同调控改善围绝经期大鼠失眠的机制研究
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作者 张彦峰 摆雪 +4 位作者 田育魁 高建辉 郭蕾 王程 刘俊昌 《环球中医药》 2025年第10期2035-2047,共13页
目的探讨腹部推拿通过调节激素组学与γ-氨基丁酸(γ-aminobutyric acid,GABA)能系统改善围绝经期失眠大鼠的作用机制。方法采用4-乙烯基环己烯二环氧化物(4-vinylcyclohexene diepoxide,VCD)建立围绝经期大鼠模型,将30只SPF级SD雌性大... 目的探讨腹部推拿通过调节激素组学与γ-氨基丁酸(γ-aminobutyric acid,GABA)能系统改善围绝经期失眠大鼠的作用机制。方法采用4-乙烯基环己烯二环氧化物(4-vinylcyclohexene diepoxide,VCD)建立围绝经期大鼠模型,将30只SPF级SD雌性大鼠通过随机数字表法分为空白组(12只)和模型组(18只)。空白组每日腹腔注射玉米油(160 mg/kg,1次/天),模型组每日腹腔注射VCD(160 mg/kg,1次/天),均连续注射16天。第17天和第56天,每组分别处死3只大鼠进行卵巢病理模型评估,共12只。造模完成后,空白组剩余6只,模型组剩余12只;模型组再次随机分为VCD组与推拿组,每组6只大鼠。空白组大鼠给予正常饲料,不做任何干预;VCD组造模后正常饲养;推拿组选取神阙、期门、关元等穴位及大鼠腹部干预,每日1次,持续4周。通过行为学旷场实验测试大鼠焦虑样行为;苏木精—伊红染色(hematoxylin and eosin staining,HE)观察卵巢卵泡发育及闭锁情况;利用液相色谱—串联质谱检测类固醇激素水平;利用高效液相色谱测定下丘脑谷氨酸(glutamate,Glu)与GABA含量;通过ELISA法检测抗缪勒管激素(anti-Müllerian hormone,AMH)、雌二醇(estradiol,E2)孕酮(progesterone,PROG)水平。结果与空白组相比,VCD组大鼠旷场实验中的活动距离、时间、穿格次数有所下降,潜伏期延长(P<0.05);卵巢结构紊乱,卵泡发育停滞(以原始卵泡为主),闭锁卵泡比例升高;卵巢细胞凋亡率随造模时间延长显著上升(P<0.05);血清中AMH、E2、PROG水平显著降低(P<0.05);雄烯二酮水平升高(P<0.05),而孕烯醇酮水平降低(P<0.01);下丘脑Glu含量显著升高(P<0.05),GABA含量呈下降趋势(P>0.05),Glu/GABA比值升高(P<0.05)。与VCD组相比,推拿干预后大鼠旷场运动指标均改善,潜伏期缩短(P<0.05);卵巢结构改善,次级卵泡及成熟卵泡数量增加,颗粒细胞层部分修复,闭锁卵泡减少;凋亡率有下降趋势但无统计学差异(P>0.05);血清中AMH、E2、PROG水平显著升高(P<0.05);睾酮、雄烯二酮水平回落,孕烯醇酮水平部分恢复(P<0.05);Glu含量下降(P<0.05),而GABA含量显著回升(P<0.01),Glu/GABA比值降低(P<0.01)。结论腹部推拿可通过激素组学与GABA能系统的协同作用,调节神经递质平衡与卵巢功能,从而改善围绝经期失眠,为非药物疗法提供了多靶点理论依据。 展开更多
关键词 腹部推拿 围绝经期失眠 激素组学 Γ-氨基丁酸 卵巢功能
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基于密度泛函理论计算Cu价态对1,4-丁二醇脱氢制备γ-丁内酯反应的影响
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作者 贺洋 曹媛 +4 位作者 王馨艺 刘宇飞 李美其 王康军 刘蝈蝈 《低碳化学与化工》 北大核心 2025年第12期48-58,共11页
γ-丁内酯(GBL)作为重要的工业原料,其需求量日益增大。Cu基催化剂上的1,4-丁二醇(BDO)脱氢是目前主要采用的GBL制备方法。然而,该方法中Cu基催化剂上的脱氢反应机制及Cu价态对反应的影响亟待深入研究。采用密度泛函理论计算并分析了Cu... γ-丁内酯(GBL)作为重要的工业原料,其需求量日益增大。Cu基催化剂上的1,4-丁二醇(BDO)脱氢是目前主要采用的GBL制备方法。然而,该方法中Cu基催化剂上的脱氢反应机制及Cu价态对反应的影响亟待深入研究。采用密度泛函理论计算并分析了Cu基催化剂上BDO脱氢制GBL的反应过程,对比了不同反应路径的能垒,并对Cu^(+)-完美型催化剂、Cu^(+)-缺陷型催化剂、Cu^(0)催化剂和Cu^(0)/Cu^(+)复合型催化剂上物质的吸附能、过渡态等进行了研究。结果表明,最可能发生的反应路径(路径A)为BDO先脱去两个氢原子后环化生成2-羟基四氢呋喃(2-HTHF),随后2-HTHF脱去两个氢原子生成GBL,路径A的决速步能垒为287.67 kJ/mol。在路径A下,Cu^(+)对BDO、2-HTHF等分子具有较强的吸附性能,而Cu^(0)则更易于活化H_(2);Cu^(+)、氧空位均能有效促进O—H键与C—H键的断裂,并活化BDO和2-HTHF;在H_(2)覆盖率较低的情况下,Cu^(0)对H_(2)合成有明显的促进作用。与其他3种催化剂相比,Cu^(0)/Cu^(+)复合型催化剂的催化性能更好。 展开更多
关键词 1 4-丁二醇 Γ-丁内酯 密度泛函理论 Cu价态 氧空位
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血清白介素37水平与急性冠脉综合征患者预后的相关性分析
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作者 张垒 《黑龙江医学》 2025年第11期1302-1304,共3页
目的:探讨血清白介素37(IL-37)水平与急性冠脉综合征患者预后的相关性。方法:选取2019年1月—2020年11月河南省人民医院收治的92例急性冠脉综合征患者作为急性冠脉综合征组,其中急性心肌梗死45例,不稳定型心绞痛47例,并以1∶1配比选取同... 目的:探讨血清白介素37(IL-37)水平与急性冠脉综合征患者预后的相关性。方法:选取2019年1月—2020年11月河南省人民医院收治的92例急性冠脉综合征患者作为急性冠脉综合征组,其中急性心肌梗死45例,不稳定型心绞痛47例,并以1∶1配比选取同期92名健康体检者作为健康对照组,比较两组受试者血清IL-37、干扰素-γ(IFN-γ)水平、心功能水平[左室射血分数(LVEF)、左心室舒张末期内径(LVEDD)],比较急性冠脉综合征组不同疾病类型患者血清IL-37、IFN-γ水平、心功能水平。结果:急性冠脉综合征组血清IL-37、IFN-γ水平较健康对照组高,差异均有统计学意义(t=36.248、25.444,P<0.05);急性心肌梗死患者血清IL-37、IFN-γ水平较不稳定型心绞痛患者高,差异均有统计学意义(t=11.263、7.359,P<0.05);急性冠脉综合征组LVEF水平较健康对照组低,LVEDD水平较健康对照组高,差异均有统计学意义(t=6.467、6.630,P<0.05);急性心肌梗死患者LVEF较不稳定型心绞痛患者低,LVEDD较不稳定型心绞痛患者高,差异均有统计学意义(t=6.604、2.220,P<0.05);Pearson分析结果显示,IL-37、IFN-γ与LVEF呈负相关,IL-37、IFN-γ与LVEDD呈正相关(r=-0.574、-0.612、0.643、0.672,P<0.05)。结论:急性冠脉综合征组患者心功能降低,血清IL-37、IFN-γ异常增高,可反映病情严重程度,用于预后评估,指导临床实施最佳治疗方案。 展开更多
关键词 急性冠脉综合征 白介素37 干扰素-Γ 心功能
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一株高产γ-氨基丁酸短乳杆菌TCCC13007全基因组测序及比较基因组分析 被引量:1
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作者 苗昊翔 张颖 +1 位作者 郭世鹏 张健 《生物技术通报》 北大核心 2025年第11期166-176,共11页
【目的】从东北酸白菜中筛选出一株高产γ-氨基丁酸(GABA)的短乳杆菌TCCC13007,对其开展全基因组测序组装工作,解析该菌株的全基因组序列信息,并进行比较基因组分析,旨在探究菌株TCCC13007高产GABA的分子机理。【方法】运用二代Illumina... 【目的】从东北酸白菜中筛选出一株高产γ-氨基丁酸(GABA)的短乳杆菌TCCC13007,对其开展全基因组测序组装工作,解析该菌株的全基因组序列信息,并进行比较基因组分析,旨在探究菌株TCCC13007高产GABA的分子机理。【方法】运用二代Illumina HiSeq技术测序,在PacBio平台完成三代测序,并结合二、三代测序数据校正结果,对菌株TCCC13007实施全基因组测序,并进行基因预测、功能注释以及比较基因组学分析。【结果】TCCC13007的基因组总长度为2.58 Mb,GC含量为45.72%,包含2581个编码基因。比较基因组分析结果显示,TCCC13007与低产GABA菌株YSJ3的亲缘关系最为接近,二者的共线性关系良好,但也存在少量的插入、倒位和易位等基因重排现象。与YSJ3相比,TCCC13007的gadA基因在基因组中的位置发生了明显的迁移,同时GadR蛋白序列的第104位突变为甘氨酸,另外该菌株中存在308个特异基因。这些特异基因可能在增强谷氨酸前体供应、维持激活谷氨酸脱羧酶(GAD)所需的酸性胞内环境、优化跨膜转运系统、辅因子与能量供应以及调控网络等方面协同发挥作用,从而使TCCC13007具备较高的GABA合成能力。【结论】全基因组测序和比较基因组学分析表明,菌株TCCC13007高产GABA特性并非依赖于基因组的显著扩张,而可能归因于更为精细和高效的基因组合及其调控网络。 展开更多
关键词 Γ-氨基丁酸 短乳杆菌 全基因组测序 基因功能注释 比较基因组学
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PEG胁迫下γ-氨基丁酸对紫花苜蓿幼苗生长及光合生理的影响
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作者 杨丽丽 南丽丽 +4 位作者 陈娜 马香香 田戈 王永 潘嗣淳 《干旱地区农业研究》 北大核心 2025年第4期53-62,共10页
以5份抗旱紫花苜蓿新品系(P1、P2、P3、P4、P5)和5份干旱敏感型苜蓿(15354、7657、7470、7740、15578)为研究材料,设置对照、干旱胁迫(-1.6 MPa PEG-6000)及干旱胁迫下分别喷施5、10、15 mmol·L-1GABA,共5个处理,探究外源GABA对干... 以5份抗旱紫花苜蓿新品系(P1、P2、P3、P4、P5)和5份干旱敏感型苜蓿(15354、7657、7470、7740、15578)为研究材料,设置对照、干旱胁迫(-1.6 MPa PEG-6000)及干旱胁迫下分别喷施5、10、15 mmol·L-1GABA,共5个处理,探究外源GABA对干旱条件下苜蓿幼苗生长发育及光合特性的影响。结果表明,供试苜蓿地上部(株高、叶面积)和地下部(根表面积、根体积、根直径和根尖数)形态指标随GABA浓度的增加均呈先升高后降低趋势,在T3处理下达到最大值,与T1相比增幅分别在7.09%~20.28%、17.35%~55.60%、10.77%~54.37%、8.48%~30.45%、14.11%~42.91%、15.36%~100.37%范围内变动。外施不同浓度GABA均能提高苜蓿的抗旱性,显著降低其地下部生物量、总根长、气孔限制值和水分利用效率,均在T3处理下达到最小值,与T1相比降幅分别在24.07%~59.83%、26.16%~58.99%、33.76%~51.44%、19.17%~26.63%范围内变化。隶属函数分析表明,在T3处理下GABA对苜蓿遭受干旱的缓解效果最佳,且对敏感型材料的缓解效应较抗旱新品系更为明显。 展开更多
关键词 苜蓿幼苗 Γ-氨基丁酸 PEG胁迫 光合参数 隶属函数
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Synthesis and Characterization of α-End Functionalized 3,4-Polyisoprene Using Fe(acac)_(3)/IITP/AliBu_(3)Catalyst
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作者 Yu-Fan Sun Ying-Nan Zhao +8 位作者 Shi-Liang Xu Yao Yu Liang Fang Li-Hua Na Qi Yang Feng Wang Heng Liu Chun-Yu Zhang Xue-Quan Zhang 《Chinese Journal of Polymer Science》 2025年第8期1367-1374,共8页
The synthesis of functionalized rubber copolymers is a topic of great research interest.In this study,we present a novel approach for the direct construction ofα-functionalized 3,4-polyisoprene through polymerization... The synthesis of functionalized rubber copolymers is a topic of great research interest.In this study,we present a novel approach for the direct construction ofα-functionalized 3,4-polyisoprene through polymerization of polar monomers and isoprene monomer.Theα-functionalized 3,4-polyisoprene was successfully synthesized via in situ sequential polymerization using the iron-based catalytic system(Fe(acac)_(3)/IITP/AliBu_(3)),exhibiting high activity and resistance to polar monomers without requiring protection of polar groups.The structure ofα-functionalized 3,4-polyisoprene was confirmed by proton nuclear magnetic resonance spectroscopy(^(1)H-NMR)and two-dimensional diffusion-ordered spectroscopy(2D DOSY)spectra analysis.The introduction of polar groups,particularly hydroxyl groups,enhanced the hydrophilicity of the copolymer.This was evidenced by a decrease in the water contact angle from 106.9°to 96.4°with increasing hydroxyl content in the copolymer. 展开更多
关键词 Iron-based catalyst 3 4-Polyisoprene α-functionalized In situ sequential polymerization HYDROPHILICITY
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2,2-二甲氧基丙烷在γ-Al_(2)O_(3)表面吸附理论研究
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作者 刘建勋 吴润东 +3 位作者 张荣斌 叶闰平 孙春艳 冯刚 《化学研究》 2025年第4期337-346,共10页
2-甲氧基丙烯(MPP)是一种重要的医药中间体。在众多生产MPP的方法中,气相裂解2,2-二甲氧基丙烷(DMP)生成MPP的工艺因其裂解产物组成简单、易于分离,具备较高的工业化潜力而备受关注,被选为研究对象。以γ-Al_(2)O_(3)作为催化剂,采用密... 2-甲氧基丙烯(MPP)是一种重要的医药中间体。在众多生产MPP的方法中,气相裂解2,2-二甲氧基丙烷(DMP)生成MPP的工艺因其裂解产物组成简单、易于分离,具备较高的工业化潜力而备受关注,被选为研究对象。以γ-Al_(2)O_(3)作为催化剂,采用密度泛函理论(Density functional theory,DFT)系统研究了DMP在γ-Al_(2)O_(3)(100)和(110)面上的吸附行为,同时考察了表面水分子对吸附性能的影响。计算结果表明,在(110)面,DMP的吸附能与表面Al原子的Lewis酸性强度呈正相关,R2高达0.99,表明DMP分子优先吸附于较强的Lewis酸性位点。在水分子覆盖的γ-Al_(2)O_(3)表面上,DMP分子在表面上的吸附强度显著降低。 展开更多
关键词 密度泛函理论 2 2-二甲氧基丙烷 γ-Al_(2)O_(3) 吸附
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干旱胁迫下γ-氨基丁酸对紫花苜蓿幼苗生理特性的影响
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作者 杨丽丽 南丽丽 +4 位作者 王永 陈娜 马香香 郭佳雨 任孟雨 《中国草地学报》 北大核心 2025年第7期38-47,共10页
为探究干旱胁迫下外施γ-氨基丁酸(γ-aminobutyric acid,GABA)对苜蓿幼苗生长的缓解效应,本研究以5份抗旱紫花苜蓿新品系和5份干旱敏感型苜蓿为研究材料,以正常供水为对照(CK),在干旱胁迫(−1.6 MPa PEG-6000)处理下外源添加0、5、10、1... 为探究干旱胁迫下外施γ-氨基丁酸(γ-aminobutyric acid,GABA)对苜蓿幼苗生长的缓解效应,本研究以5份抗旱紫花苜蓿新品系和5份干旱敏感型苜蓿为研究材料,以正常供水为对照(CK),在干旱胁迫(−1.6 MPa PEG-6000)处理下外源添加0、5、10、15 mmol/L(记为T1、T2、T3、T4)浓度的GABA,分析不同浓度GABA处理对苜蓿幼苗生理特征的影响。结果表明,外施GABA能显著提高干旱胁迫下供试苜蓿超氧化物歧化酶、过氧化物酶、过氧化氢酶、叶片相对含水量和根系活力,降低脯氨酸、可溶性糖、可溶性蛋白、丙二醛、过氧化氢含量和超氧阴离子产生速率。隶属函数分析表明,在T3处理下GABA对苜蓿遭受干旱的缓解效果最佳,且对敏感型材料缓解效应较抗旱新品系更为明显。研究结果为GABA在苜蓿耐旱栽培中的合理使用提供了理论依据。 展开更多
关键词 Γ-氨基丁酸 苜蓿 干旱胁迫 生理特征 隶属函数
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