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Substrate specificity in the biomimetic catalytic aerobic oxidation of styrene and cyclohexanone by metalloporphyrins: kinetics and mechanistic study

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Green Chemical Engineering 2021年第2期2卷 217-223页

作者： Xian-Tai Zhou Hong-Bing ji Fine Chemical Industry Research Institute Sun Yat-sen UniversityGuangzhou510275China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming525000China

Substrate specificity is a hallmark of enzymatic *** this work,the biomimetic catalytic oxidation of styrene and cyclohexanone by iron(III)porphyrins and molecular oxygen was carried out,and remarkable differences in efficiency were *** specificity of the substrates for biomimetic catalytic oxidation was investigated by kinetics and mechanistic *** studies revealed that the oxidation of styrene followed Michaelis-Menten kinetics with KM=8.99 mol l^(-1),but the oxidation of cyclohexanone followed first-order kinetics with kobs=1.46×10^(-4) s^(-1),indicating that the styrene epoxidation by metalloporphyrins exhibited characteristics of enzyme-like catalysis,while the oxidation of cyclohexanone was in agreement with the general rules of chemical *** catalytic mechanisms for the two substrates were discussed by operando electron paramagnetic resonance spectroscopy,operando uV-vis spectroscopy,and KI/starch *** specificity was concluded to be attributed to the stability of high-valence species and oxygen transfer rate.

关键词： Substrate specificity Kinetics Oxidation Metalloporphyrins Mechanism

抗HER2/neu单链抗体增强TNF-α对卵巢癌细胞的抗肿瘤活性

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应用与环境生物学报 2006年第4期12卷 543-546页

作者：蒋琳纪剑飞阎锡蕴吕安国吴文芳中国科学院沈阳应用生态研究所 Beckman Research Institute City of Hope National Medical Center 1500 Duarte Rd. Duarte CA 91010 USA 中国科学院生物物理研究所北京100101

为了探索抗HER2/neu单链抗体与TNF-α联合应用对表面过度表达HER2/neu卵巢癌细胞的生物效应,同时构建了抗HER2/neu单链抗体scFvC6.5的原核表达载体和人TNF-α的原核表达载体,将上述两种重组子分别转化入感受态宿主菌Bl21(DE3),得到稳定... 详细信息

为了探索抗HER2/neu单链抗体与TNF-α联合应用对表面过度表达HER2/neu卵巢癌细胞的生物效应,同时构建了抗HER2/neu单链抗体scFvC6.5的原核表达载体和人TNF-α的原核表达载体,将上述两种重组子分别转化入感受态宿主菌Bl21(DE3),得到稳定表达.表达产物主要以包含体形式存在;包含体经过溶解、变性、复性和纯化,得到了分纯的产物.SDS-PAGE和Western-blot检测结果证实,蛋白表达正确.ElISA法验证了scFvC6.5和人TNF-α具有与卵巢癌细胞SKOV-3的结合活性.MTT细胞毒活性试验进一步表明,相对于单独使用TNF-α,联合应用上述两个重组蛋白细胞毒效应明显提高,SKOV-3细胞对TNF-α的敏感性增强.这将为抗HER2/neu抗体的联合抗肿瘤疗法提供一种新的途径,具有潜在的临床应用价值.

关键词：抗HER2/neu单链抗体肿瘤坏死因子基因表达联合应用

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二位置陀螺寻北仪静态误差分析

压电与声光 2000年第5期22卷 309-312页

作者：卜继军魏贵玲吕志清四川压电与声光技术研究所重庆400060

对二位置寻北仪的静态误差源进行了详细的讨论 ,给出了一种寻北仪静态误差分析方法 ,并得出在各误差源作用下的误差模型。分析表明 ,由于几种典型的误差源产生的寻北误差与方位角的三角函数成正比或为常值 ,有较强的规律性。

关键词：寻北仪静态误差误差源陀螺

Parisian ruin over a finite-time horizon

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Science China Mathematics 2016年第3期59卷 557-572页

作者： DEBICKI Krzysztof HASHORVA Enkelejd ji lan Peng Mathematical Institute University of Wroclaw Department of Actuarial Science University of Lausanne

For a risk process R_u(t) = u + ct- X(t), t≥0, where u≥0 is the initial capital, c > 0 is the premium rate and X(t), t≥0 is an aggregate claim process, we investigate the probability of the Parisian ruin P_S(u, T_u) = P{inf (t∈[0,S]_(s∈[t,t+T_u])) sup R_u(s) u > *** X being a general Gaussian process we derive approximations of P_S(u, T_u) as u →∞. As a by-product, we obtain the tail asymptotic behaviour of the infimum of a standard Brownian motion with drift over a finite-time interval.

关键词： Parisian ruin Gaussian process lévy process fractional Brownian motion infimum of Brownian motion generalized Pickands constant generalized Piterbarg constant

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欧洲七叶树体细胞胚发生的细胞组织学观察

上海农业学报 2013年第1期29卷 24-28页

作者：吕秀立施季森上海市园林科学研究所上海200232 南京林业大学森林资源与环境学院南京210037

利用石蜡切片法对欧洲七叶树体细胞胚胎发生进行细胞组织学观察,结果表明:胚性细胞具有细胞小、大小均一、胞质浓、细胞核大、核仁明显等特点,且分裂速度快:而非胚性细胞体积较大、核小、细胞质稀薄、细胞之间间隙较多,不易成团。体细... 详细信息

利用石蜡切片法对欧洲七叶树体细胞胚胎发生进行细胞组织学观察,结果表明:胚性细胞具有细胞小、大小均一、胞质浓、细胞核大、核仁明显等特点,且分裂速度快:而非胚性细胞体积较大、核小、细胞质稀薄、细胞之间间隙较多,不易成团。体细胞胚发生主要起源于表层的单细胞,依次经过2-细胞原胚、多细胞原胚、球形胚、心形胚、鱼雷形胚和子叶胚等与合子胚发育类似的过程,再生植株。欧洲七叶树离体本培养产生的体细胞胚具备发育完善的V型维管束、茎尖分生组织以及根尖分生组织,具有明显的两极性和相对的独立性。

关键词：欧洲七叶树体细胞胚 Ⅴ型维管束两极性

BiFeO_3空间选择性光化学还原Ag及光催化活性

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无机化学学报 2014年第3期30卷 492-498页

作者：吴子伟吕晓萌沈佳宇谢吉民江苏大学化学化工学院镇江212013

采用溶胶-凝胶法和光还原沉积法制备出Ag改性的纳米BiFeO3粒子，对复合材料进行了FESEM、XRD、XPS、FTIR、uV-Vis/DRS等分析和表征。考察了波长365 nm以上的光照下，铁磁性材料的空间选择性光化学反应对复合材料的结构、形貌以及光谱性... 详细信息

采用溶胶-凝胶法和光还原沉积法制备出Ag改性的纳米BiFeO3粒子，对复合材料进行了FESEM、XRD、XPS、FTIR、uV-Vis/DRS等分析和表征。考察了波长365 nm以上的光照下，铁磁性材料的空间选择性光化学反应对复合材料的结构、形貌以及光谱性质的影响。以罗丹明B为模拟污染物，考察了纳米Ag-BiFeO3粒子的可见光光催化活性以及稳定性。结果表明：通过光化学沉积，不仅增强了BiFeO3在200~800 nm光照下的响应，而且抑制了光腐蚀现象，提高了BiFeO3的稳定性。在波长大于400 nm的光照射12 h后单纯纳米BiFeO3粒子对罗丹明B脱色率约为74%，而Ag-BiFeO3复合材料6 h后约为90%，并且重复使用3次后光催化效果基本不变。

关键词：银铁酸铋粒子空间选择性光催化

Comparison between recombinant human parathyroid hormone(1-34) and elcatonin in treatment of primary osteoporosis

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Asian Pacific Journal of Tropical Medicine 2015年第1期8卷 79-84页

作者： Yan Yang Xue-Jun Zhang Xian-Jun Zhu lei Zhang Ming-jing Bao Yang Xian ji-Chuan wu li-Mei liu Peng-Qiu li Department of Endocrinology Sichuan Provincial People's Hospital

Objective:To evaluate the efficacy and safety of rhPTH(1-34) ***:Sixty palients with primary OP were randomly divided into two groups according to the ratio of 3:***(1-34) group(PTH group) was treated with subcutaneous injection of rhPTH(1-34) 20 μg daily for 18 months,and the elcalonin group(CT group) was treated with intramuscular injection of elcatonin 20 u weekly for 12 *** mineral density(BMD) of the lumbar spine 2-4(l_(2-4))and femoral neck,serum calcium and phosphorus,urinary calcium,serum hone specific alkaline phosphatase(BSAP).and urinary c-terminal telopeptides of type Ⅰ collagen/creatinine(uCTX-Ⅰ /Cn were tested at baseline,and *** 18 months after ***:In PTH *** of l_(2-4),at 6,*** 18 months,BDM of Femoral neck at 18 month,BSAP at 6 and 12 months and uCTX- Ⅰ /Cr at 6.12 and 18 months were all significantly *** CT *** of l_(2-4) at12 month and that of femoral neck at 12 and 18 months were significantly elevated,while HSAP was significantly decreased at 12 and 18 months,and no significant difference on CTX- Ⅰ /Cr was *** BMD growth and growth rate between two groups were *** group had better improvement in l_(2-4) BMD and growth rate than CT group at *** 18 *** growth and growth rale of femoral neck al 12 month and its growth at 18 month in CT group were higher than in PTH group,hut there was no significant difference between two groups regarding the growth rates at 18 ***,there were no significant differences regarding the rales ol adverse reactions between two ***:rhPTH(1—34),is safe and effective in the treatment of primary *** is superior to elcatonin in improving vertebral HMD at onset time,growth rate and growth range,but inferior to elcatonin at HMD of femoral neck.

关键词： Recombinant human parathyroid hormone Bone density Primary osteoporosis Elcatonin

联苯-2,4,4′,6-四甲酸银、咪唑-菲啰啉-苯氧乙酸镉配位聚合物的合成、结构及与DNA的相互作用（英文）

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无机化学学报 2017年第10期33卷 1869-1875页

作者：鲁雅吕天喜胡未极吴小勇赵国良浙江师范大学行知学院金华321004 浙江师范大学化学与生命科学学院金华321004

由联苯-2,4,4′,6-四甲酸(H_4BPTC,C_(16)H_(10)O_8)和2-4-(1H-咪唑-2-[4,5-f][1,10]菲啰啉基)苯氧乙酸(HPIMPHC,C_(21)H_(14)N_4O_3),水热合成了2种新型配位聚合物[Ag_4(BPTC)]_n(1),[Cd(PIMPHC)_2]_n(2)。用元素分析、红外光谱、热重分析和X射线单晶衍射对配合物进行了表征和结构分析。配合物1属三斜晶系,空间群为P1;Ag(Ⅰ)的配位数分别为4、3、2,配位构型为变形四面体、平面三角形和V型。配合物2属正交晶系,空间群为Pbcn;Cd(Ⅱ)的配位数为6,配位构型为变形的八面体,Cd(Ⅱ)离子间通过三齿配体PIMPHC-桥连,形成2D网状结构。用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。

关键词：联苯-2,4,4′,6-四甲酸 2-4-(1H-咪唑-2-[4,5-f]菲啰啉基)苯氧乙酸 Ag(Ⅰ) Cd(Ⅱ) DNA

Riemann-Hilbert problem for the fifth-order modified Korteweg–de Vries equation with the prescribed initial and boundary values

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Communications in Theoretical Physics 2023年第6期75卷 27-38页

作者： Beibei Hu ling Zhang ji lin Hanyu Wei Department of Physics Zhejiang Normal UniversityJinhua 321004China School of Mathematics and Finance Chuzhou UniversityAnhui 239000China College of Mathematics and Statistics Zhoukou Normal UniversityZhoukou 466001China

In this paper,we investigate the fifth-order modified Korteweg-de Vries(mKdV)equation on the half-line via the Fokas unified transformation *** show that the solution u(x,t)of the fifth-order mKdV equation can be represented by the solution of the matrix Riemann-Hilbert problem constructed on the plane of complex spectral parameter θ.The jump matrix l(x,t,θ)has an explicit representation dependent on x,t and it can be represented exactly by the two pairs of spectral functions y(θ),z(θ)(obtained from the initial value u0(x))and Y(θ),Z(θ)(obtained from the boundary conditions v0(t),{vk(t)}_(1)^(4)).Furthermore,the two pairs of spectral functions y(θ),z(θ)and Y(θ),Z(θ)are not independent of each other,but are related to the compatibility condition,the so-called global relation.

关键词： Riemann-Hilbert problem fifth-order modified Korteweg-de Vries equation initialboundary value problems Fokas unified transformation approach