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Interfacial Behaviors of Azocalixarene Derivatives at the Air/Water Interface and Photochromism in the Langmuir-Blodgett Films

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Chinese Chemical Letters 2005年第11期16卷 1543-1546页

作者： Xun GUO Li ZHANG Guo Yuan LU mei fang YIN fang liu Ming Hua liu Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 Laboratory of Colloid and Interface Science Center for Molecular Science Institute of Chemistry the Chinese Academy of Science Beijing 100101

The interfacial behaviors of the non-typical amphiphilic compound p-methylphenylazocalix[4]arene 1 and p-chlorophenylazocalix[4]arene 2 at the air/water interface and photochromism in the Langmuir-Blodgett films were studied by surface pressure-area isotherm and UV-Vis spectra. The results indicate that they can form stable monolayers at the air / water interface although they have no hydrophobic alkyl chains, and their LB film underwent reversible trans-cis photoisomerization on UV and daylight illumination.

关键词： Azocalixarene photochromism monolayer LB film.

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甲烷在钠基蒙脱土吸附的第一性原理研究

原子与分子物理学报 2025年第2期42卷 8-14页

作者：方志杰李博宋昌辉刘美玲何秋芝刘翔莫曼广西科技大学电子工程学院柳州545006 广西科技大学土木建筑工程学院柳州545006 广西科技大学医学部柳州545006

随着经济的发展,能源需求日益增加,为了弥补国内少油缺气短板,页岩气的开发成为近期新能源的热点,探索页岩气储存规律是页岩气能源开发的关键所在.本文采用密度泛函理论的第一性原理方法,计算甲烷(CH_(4))在钠基蒙脱土表面和层间的吸附... 详细信息

随着经济的发展,能源需求日益增加,为了弥补国内少油缺气短板,页岩气的开发成为近期新能源的热点,探索页岩气储存规律是页岩气能源开发的关键所在.本文采用密度泛函理论的第一性原理方法,计算甲烷(CH_(4))在钠基蒙脱土表面和层间的吸附能,对比吸附前后的态密度和物理结构以及差分电荷密度.结果表明:钠基蒙脱土表面吸附中,甲烷最佳选择是桥位,吸附能为-0.08eV,被吸附后甲烷的键长和键角变化率均小于0.96%.层间吸附中,伴随着甲烷吸附量增加,纳基蒙脱土体积向c轴方向线性增加,a、b轴方向则变化不大.总态密度随着吸附量的增加,总能级数量也增加,甲烷分子的分波态密度峰向低能级移动.本文的研究成果,从原子角度分析了甲烷在蒙脱石表面以及层间的吸附能力,为解释页岩气在页岩储存规律提供理论依据.

关键词：钠基蒙脱土第一性原理甲烷吸附态密度

Crystal Structure of (R)-3,3′-Bis(benzyloxymethyl)-1,1′-bi-2,2′-naphthol and Its Applications in Enantioselective Lewis Acid Catalyzed Addition of Diethylzinc to Aldehydes

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Chinese Journal of Structural Chemistry 2007年第2期26卷 133-138页

作者： liu Guo-Hua YU Han XUE Yun-Ning YAO mei fang Hai-Bin Department of Chemistry College of Life and Environmental Science Shanghai Normal University Shanghai 200234 China

The title compound （R）-3,3＇-bis（benzyloxymethyl）-1,1＇-bi-2,2＇-naphthol （R）-3 has been synthesized through the deprotection of MOM group by iprOH/HCl in 83% isolated yield and the suitable single crystals for X-ray diffraction were obtained by recrystallization at room temperature from the mixture solvents. Crystallographic data for （R）-3： C36H30O4, Mr = 526.60, triclinic, space group P1, a = 10.057（6）, b = 11.934（7）, c = 12.314（6） A, α = 85.52（2）, β = 70.245（13）, γ = 76.554（11）°, Z= 2, V 1352.8（13） A^3, Dc = 1.293 g/cm^3, F（000） = 556, R = 0.0745, wR = 0.1933 and #（MoKa） = 0.083 mm^-1. The title compound （R）-3 was found to be effective in the enantioselective addition of diethylzinc to aldehydes both in the presence and absence of Ti（Oipr）4. In the latter case, （R）-3 showed much higher catalytic activity and enantioselectivity than （R）-BINOL＇s.

关键词： crystal structure BINOL derivative asymmetric addition

Perfect Matching in k-partite k-graphs and 3-uniform HM-bipartite Hypergraphs

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Acta Mathematicae Applicatae Sinica 2020年第3期36卷 636-641页

作者： Chun-qiu fang mei LU Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

Let H=(V,E)be an n-balanced k-partite k-graph with partition classes V1,...,*** for every legal(k-1)-tuple f contained in V\V1 and for every legal(k-1)-tuple g contained in V\Vk such that f∪g■E(H),we have d(f)+d(g)≥n+*** this paper,we prove that under this condition H must have a perfect *** result of this paper is about the perfect matching in 3-uniform hm-bipartite *** G be a 3-uniform hm-bipartite hypergraph with one of whose sides V1 has the size n,the another side V2 has size 2 *** for all the legal 2-tuple f with|f∩V1|=1 and for all the legal 2-tuple g with|g∩V1|=0,we have d(f)≥n-2 and d(g)>n/2,then G has a perfect matching.

关键词： Perfect matching k-partite k-graph hm-bipartite hypergraph

Practical choice for robust and efficient differentiation of human pluripotent stem cells

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World Journal of Stem Cells 2020年第8期12卷 752-760页

作者： mei fang Li-Ping liu Hang Zhou Yu-mei Li Yun-Wen Zheng Institute of Regenerative Medicine Affiliated Hospital of Jiangsu UniversityJiangsu UniversityZhenjiang 212001Jiangsu ProvinceChina School of Biotechnology and Heath Sciences Wuyi UniversityJiangmen 529020Guangdong ProvinceChina Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery University of Tsukuba Faculty of MedicineTsukubaIbaraki 305-8575Japan City University School of Medicine YokohamaKanagawa 234-0006Japan Division of Regenerative Medicine Center for Stem Cell Biology and Regenerative MedicineThe Institute of Medical Sciencethe University of TokyoTokyo 108-8639Japan

Human pluripotent stem cells(hPSCs)have the distinct advantage of being able to differentiate into cells of all three germ *** cells or tissues derived from hPSCs have many uses such as drug screening,disease modeling,and transplantation *** are currently a wide variety of differentiation methods ***,most of the existing differentiation methods are unreliable,with uneven differentiation efficiency and poor *** the same time,it is difficult to choose the optimal method when faced with so many differentiation schemes,and it is time-consuming and costly to explore a new differentiation ***,it is critical to design a robust and efficient method of *** this review article,we summarize a comprehensive approach in which hPSCs are differentiated into target cells or organoids including brain,liver,blood,melanocytes,and mesenchymal *** was accomplished by employing an embryoid body-based three-dimensional(3D)suspension culture system with multiple cells *** method has high stable differentiation efficiency compared to the conventional 2D culture and can meet the requirements of clinical ***,ex vivo co-culture models might be able to constitute organoids that are highly similar or mimic human organs for potential organ transplantation in the future.

关键词： Human pluripotent stem cells Three dimensional Embryoid body Differentiation Efficient Three germ layers

Influence of ignition condition on the growth of silicon thin films using plasma enhanced chemical vapour deposition

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Chinese Physics B 2012年第1期21卷 314-319页

作者： Zhang Hai-Long liu Feng-Zhen Zhu mei-fang liu Jin-Long Graduate University of Chinese Academy of Sciences Beijing 100049China

The influences of the plasma ignition condition in plasma enhanced chemical vapour deposition （PECVD） on the interfaces and the microstructures of hydrogenated microcrystalline Si （μc-Si：H） thin films are investigated. The plasma ignition condition is modified by varying the ratio of Sill4 to H2 （RH）. For plasma ignited with a constant gas ratio, the time-resolved optical emission spectroscopy presents a low value of the emission intensity ratio of Ha to Sill＊（Iuα//SiH＊） at the initial stage, which leads to a thick amorphous incubation layer. For the ignition condition with a profiling RH, the higher IHα/ISiH＊ values are realized. By optimizing the RN modulation, a uniform crystallinity along the growth direction and a denser αc-Si：H film can be obtained. However, an excessively high IRα/ISIH＊ may damage the interface properties, which is indicated by capacitance-voltage （C-V） measurements. Well controlling the ignition condition is critically important for the applications of Si thin films.

关键词： plasma enhanced chemical vapour deposition microcrystalline silicon ignition condition

TiO_2 photocatalytic antifungal technique for crops diseases control

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Journal of Environmental Sciences 2006年第2期18卷 397-401页

作者： LU Jian-wei LI fang-bai GUO Ting LIN Lan-wen HOU mei-fang liu Tong-xu Faculty of Resource and Environment Center China Agricultural University Wuhan 430070 China Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control Guangdong Institute of Eco-Environment and Soil Sciences Guangzhou 510650 China South China Institute of Botany Chinese Academy of Sciences Guangzhou 510650 China

TiO2 and 1% Ce^3＋-TiO2 prepared by hydrothermal method were characterized by means of XRD and UV-visible diffusive reflectance spectra（DRS）. The results of DRS analysis indicated that the 1% Ce^3＋-TiO2 catalyst had significant optical absorption in the visible region between 400-450 nm because electrons could be excited from the valence band of TiO2 or cerium oxides to Ce 4f level. To investigate the photocatalytic activity of different catalysts for crop fungal disease control, a series of Quine tests were carried out for cucumber powdery mildew and litchi downy blight control in home-made photocatalytic reactor. The results showed that TiO2 photocatalysis technique should be effective to inhibit the growth of fungal diseases to some extent and P-25 had a higher activity for antifungal control than home-made TiO2 catalysts. TiO2-A prepared with Ti（SO4）2 is more active to contro 1 antifungal disease than TiO2-B prepared with TiOSO4 as precursor because the crystalline of TiO2-A was higher than that of TiO2-B. The antifungal index litchi downy blight control was greatly enhanced by doping 1% cerium ion. The antifungal index of 1.0%Ce3^＋-TiO2 was（47.0 ± 4.7）%, （82.2 ± 3.5）%, （100 ±0.0）% under indoor weaker light, solar light and black light, respectively. The results of field experiments showed that the antifungal index of 1.0%Ce^3＋-TiO2 was more than that of P-25. The antifungal index of 1.0%Ce^3＋-TiO2 was （81.7 ± 6.5）%, （67.5 ±4.7）%, （38.6±1.9）% for litchi downy blight, maize southern leaf spot, and rice blast, respectively. It was concluded that TiO2 photocatalysis technique should be an effective way for litchi fungal disease control in practice.

关键词： titanium dioxide photocatalytic fungal disease solar light litchi downy blight

重组人载脂蛋白AI_(米兰变体)在大肠杆菌中的高效表达

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微生物学通报 2005年第4期32卷 107-111页

作者：丁满生马文峰张梅芳刘大涛郭美锦庄英萍储炬龚邦强华东理工大学生物反应器国家重点实验室上海200237 上海凯曼生物科技有限公司上海200233 上海信谊药业有限公司药研所上海200234

通过大肠杆菌表达系统来生产重组人载脂蛋白AIM(proapolipoprote in AIM,proapoAIM)。整个proapo AIM基因被分成两个片断,通过RT-PCR的方法合成。在对该基因的上游部分进行改造后,插入到表达载体pBV220中进行表达。蛋白的表达量达到45%... 详细信息

通过大肠杆菌表达系统来生产重组人载脂蛋白AIM(proapolipoprote in AIM,proapoAIM)。整个proapo AIM基因被分成两个片断,通过RT-PCR的方法合成。在对该基因的上游部分进行改造后,插入到表达载体pBV220中进行表达。蛋白的表达量达到45%左右,蛋白的表达形式为包涵体。包涵体通过疏水柱进行柱上复性,复性后的蛋白具有良好的生物活性。

关键词：载脂蛋白AI Milano 包涵体疏水柱复性

Multi-site occupancies and dependent photoluminescence of Ca_(9)Mg_(1.5)(PO_(4))_(7):Eu^(2+) phosphors:A bifunctional platform for optical thermometer and plant growth lighting

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Journal of Rare Earths 2023年第10期41卷 1503-1511,I0002页

作者： Ruiyu Mi Yan-gai liu Lefu mei Zhaohui Huang Minghao fang Xiaowen Wu Xin Min Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing100083China

Herein,we demonstrate an optical thermometer based on single Eu^(2+)doped Ca_(9)Mg_(1.5)(PO_4)_7 phosphors,which were prepared by traditional solid-state reaction technique under a reduction *** on the bond length obtained by the crystal structure refinement and the dependent photoluminescence performances allow to assign the two distinct emission bands to Eu^(2+)ions occupied Cal-Ca3 and Mg2 ***,the blue and red emitting bands perfectly match with the photosynthetic action spectrum,which can enhance the indoor plant *** optimal doping content of Eu^(2+)ions in this Ca_(9)Mg_(1.5)(PO_(4))_(7)system is 3 mol%.The corresponding concentration quenching effect is verified as dipole-dipole interaction with the critical distance of 3.315 ***,by exploiting the fluorescence intensity technique,the optical thermal resistance properties of Ca_(9)Mg_(1.5)(PO_4)_7:Eu^(2+)are identified based on the temperature dependent emission spectra in a range of 303-523 *** detail,the maximum absolute and relative sensitivity S_(a)and S_(r)of Ca_9Mg_(1.5)(PO_(4))_(7):Eu^(2+)thermometer are as high as 0.637%/K and 0.3155 K^(-1),***,the Eu^(2+)doped Ca_(9)Mg_(1.5)(PO_(4))_(7)phosphors establish a bifunctional platfo rm for both optical the rmometer and plant growth lighting via multi-site occupancies.

关键词： Eu^(2+)site occupancies Photoluminescence Plant growth lighting Fluorescence intensity ratio Thermometer Rare earths