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Chinese Journal of chemistry 1992年第3期10卷 206-212页

作者： YANG, Jia-Zhen MEN, Dian-Yuan guan, xiu-dan department of chemistry, liaoning university, shenyang, liaoning 110036 department of chemistry Liaoning University Shenyang Liaoning 110036

The thermodynamic ionization constant K° of p-nitrophenol in {10 mass% ethanol-water} mixed solvent is derived from measurements of its absorption spectrum and pH by the two methods: Debye--Huckel extrapolation and polynomial approximation proposed by us in suitable buffer solution at constant ionic strength from 0.1 to 2.0 ***^(-1) at 298.2 ± 0.2 K. The results from both methods are pK° =7.406 and 7.415, respectively. The effect of medium on the ultraviolet spectra of p-nitrophenol has been discussed.

关键词： Determination of the thermodynamic dissociation constant of p-nitrophenol in EtOH

Effect of vasoactive intestinal peptide on pulmonary surfactants phospholipid synthesis in lung explants

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Acta Pharmacologica Sinica 2004年第12期25卷 86-92页

作者： Lian LI, Zi-qiang LUO2, Fu-wen ZHOU, dan-dan FENG, Cha-xiang guan, Chang-qing ZHANG, xiu-hong SUN department of Physiology, Xiangya Schoolof Medicine, CentralSouth university, Changsha 410078, China department of Physiology Xiangya School of Medicine Central South University Changsha 410078

AIM: To investigate the effect of vasoactive intestinal peptide (VIP) on pulmonary surfactants (PS) phospholipid synthesis in cultured lung explants. METHODS: Lung explants were cultured with serum-free medium, [methyl- 3H]choline incorporation, total phospholipid, phosphatidylcholine, activity of choline-phosphate cytidylyltransferase (CCT) and CCTα mRNA level in lung explants were determined. RESULTS: (1) VIP (10-10-10-7mol/L) for 16 h promoted [methyl-3H]choline incorporation in dose dependence and VIP (10-8mol/L) for 2 h-16 h promoted [methyl- 3H]choline incorporation in time dependence. (2) VIP (10-8 mol/L) enhanced the contents of total phospholipids and phosphatidylcholine in lung explants. (3) VIP (10-10-10-7mol/L) elevated microsomal CCT activity of lung explants in dose dependence. (4) VIP (10-8 mol/L) increased expression of CCTα mRNA in lung explants and alveolar type II cells (ATII). (5) [D-P-Cl-Phe(6)-Leu(17)]-VIP (10-6 mol/L), a VIP receptors antagonist, abolished the increase of [3H]choline incorporation, microsomal CCT activity and CCTα mRNA level induced by VIP (10-8 mol/L) in lung explants. CONCLUSION: VIP could enhance synthesis of phosphatidylcholine, the major compo- nent of pulmonary surfactants by enhancing microsomal CCT activity and CCTα mRNA level via VIP receptor- mediated pathway.

关键词： vasoactive intestinal peptide pulmonary surfactants choline-phosphate cytidylyltransferase

Synthesis and Crystal Structure of LanthanideHetero-polymolybdate Complex:(NH_4)_(12)H_(10)〔Nd_4Mo_(29)O_(104)(H_2O)_(12)〕·22H_2O

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Chinese Journal of Structural chemistry 1997年第3期16卷 239-246页

作者： CAI xiu-Zhen WANG Shi-Ming guan Huai-Min HUANG Jin-Feng(department of chemistry, Institute of Polymer Science,Fujian Normal university, Fuzhou, 350007)LIN Yong-Hua XING Yan(Changchun Institute of Applied chemistry, the Chinese Academyof Sciences, Chan department of chemistry Fujian Normal University Fuzhou 350007 China Institute of Polymer Science Fujian Normal University Fuzhou 350007 China Changchun Inst. of Applied chemistry Chinese Academy of Sciences Changchun 130022 China

The title complex crystallized in triclinic system with space group P1;Mr=5862. 35 a= 17.04(1), b= 18. 989(5), c= 24. 240(6) A ;a= 100. 18(2), β=92. 24(3), γ= 113. 04(3)°; V=7054(6) A3, Z=2, Dc= 2. 664 g. cm-3, F(000) =5306, μ= 4. 036 mm-1 and final R= 0. 0763 and Rw= 0. 2176 for 15951 reflections [Ⅰ>2δ(I)]. The Nd(Ⅲ) coordinated with 9 oxygen atoms forms a mono-capped square-antiprism configuration, while the Mo (Ⅵ) ions have several different coordinationnumbers such as 4, 5 and 6 with different configurations such as tetrahedron, distortedsquare pyramid and octahedron respectively.

关键词： neodymium heteropolymolybdate crystal structure synthesis

Arabidopsis shaker pollen inward K^+ channel SPIK functions in SnRK1 complex-regulated pollen hydration on the stigma

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Journal of Integrative Plant Biology 2017年第9期59卷 604-611页

作者： dan-dan Li Huan guan Fei Li Chang-Zhen Liu Yu-xiu Dong Xian-Sheng Zhang Xin-qi Gao State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai'an 271018China

Pollen hydration is a critical step that determines pollen germination on the stigma. KINγ is a plantspecific subunit of the SNF-1-related protein kinase 1 complex （SnRK1 complex）. In pollen of the Arabidopsis kinβγ mutant, the levels of reactive oxygen species were decreased which lead to compromised hydration of the mutant pollen on the stigma. In this study, we analyzed gene expression in kinβγ mutant pollen by RNA-seq and found the expression of inward shaker K^＋ channel SPIK was down-regulated in the kinβγ /pollen. Furthermore, we showed that the pollen hydration of the Arabidopsis spik mutant was defective on the wild-type stigma, althoughthe mutant pollen demonstrated normal hydration in vitro. Additionally, the defective hydration of spik mutant pollen could not be rescued by the wild-type pollen on the stigma, indicating that the spik mutation deprived the capability of pollen absorption on the stigma. Our results suggest that the Arabidopsis SnRK1 complex regulates SPIK expression, which functions in determining pollen hydration on the stigma.

关键词： Arabidopsis shaker pollen inward K channel SPIK functions in SnRK1 complex-regulated pollen hydration on the stigma

Synthesis and Crystal Structure of Neodymium Heteropolymolybdate Complex Na_4(NH_4)_(10)[Nd_4 Mo_(29)O_(100)(H_2O)_(16)]·34H_2O

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Chinese Journal of Structural chemistry 1997年第4期16卷 328-334页

作者： CAI xiu-Zhen WANG Shi-Ming HUANG Jin-Feng guan Huai-Min(department of chemistry , Institute of Polymer Science ,Fujian Normal university, Fuzhou 350007)LIN Xiang(Fujian Institute of Research on the Structure of Matter,the Chinese Academy of Sciences, F department of chemistry Fujian Normal University Fuzhou 350007 China Institute of Polymer Science Fujian Normal University Fuzhou 350007 China Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou 350002 China

Single crystals of the title complex Na4 (NH4)10[Nd4Mo29O100(H2O)16]·34H2O obtained from the reaction of (NH4)6Mo7O24 and Nd (NO3)3, crystallize in themonoclinic, space group C2/c, with a= 19. 556(8), b= 43. 22 (2), c= 20. 389 (7) A,β= 117. 43(3)°, V= 15297(10) A3, Z=4, Dc= 1. 331g· cm-3, F(000) =5824, μ=1. 875 mm-1, final R(wR) = 0. 0816 (0. 2039) for 6128 unique intensity data [I≥2σ(I)]. In the molecule, each Nd heteroatom is coordinated by nine oxygen atoms with amono-capped square-antiprism configuration[1], while the Mo (VI) ions have severaldifferent coordination numbers (4, 5 and 6) with different configurations such as tetra-hedron, distorted square pyramid and octahedron respectively.

关键词： neodymium complex heteropolymolybdate crystal structure synthesis

Synthesis and structure a luminescent copper（Ⅰ） thiophene-pyrazole complex

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Synthesis and structure a luminescent copper（Ⅰ） thiophene...

Tissue factor with age-related macular degeneration

第六届全国物理无机化学会议

作者： Liu-Jun Guo,Wen-xiu Ni,dan Li~* department of chemistry,Shantou university,guangdong 515063

＜正＞More and more coordination compounds based on Cu（I）-pyrazolates were investigated for their interesting photoluminescence properties and potential applications in photofunctional materials and chemical sensors. Dependent on the steric crowd,coordination compounds based on Cu（I）-pyrazolated have extensively reported

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International Journal of Ophthalmology(English edition) 2012年第5期5卷 609-613页

作者： guan-Feng Wang xiu-Lan Zou department of Ophthalmology Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510010 Guangdong Province China Jinan university Guangzhou 510630 Guangdong Province China

Wet age-related macular degeneration which incidence increases year by year is a blinding eye disease, but current clinical methods of treatment on this disease are limited and the outcome is not ideal. Recent studies have found abnormally high expression of tissue factors which are targets for the treatment of wet age-related macular degeneration to achieve a certain effect in the choroidal neovascularization. Related literatures are reviewed as following.

关键词： wet age-related macular degeneration choroidal neovascularzation tissue factor photodynamic therapy immunotherapy

Direct Arylation of Substituted Pyridines with Arylboronic Acids Catalyzed by Iron(Ⅱ) Oxalate

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Chinese Journal of chemistry 2014年第12期32卷 1294-1298页

作者： Yibo Huang dan guan Liang Wang department of Pharmacy Changzhou Institute of Engineering and TechnologyChangzhouJiangsu 213164China Jiangsu Provincial Key Laboratory of Fine Petrochemical Engineering ChangzhouJiangsu 213164China School of Petrochemical Engineering Changzhou UniversityChangzhouJiangsu 213164China

The direct arylation of substituted pyridines with several arylboronic acids has been *** transformation could proceed readily at ambient temperature using inexpensive reagents:iron(Ⅱ)oxalate as a catalyst,potassium persulfate as a co-oxidant,which can afford the arylated products in mild to good *** mechanism is presumed to proceed through a nucleophilic radical addition to the pyridines with in situ reoxidation.

关键词： direct arylation substituted pyridine arylboronic acid Iron(Ⅱ)oxalate

Cryptanalysis of an image encryption scheme based on the Hill cipher

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2008年第8期9卷 1118-1123页

作者： Cheng-qing dan ZHANG guan-rong CHEN department of Electronic Engineering City University of Hong Kong Kowloon Tong Hong Kong China School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

This paper studies the security of an image encryption scheme based on the Hill cipher (Ismail et al., 2006) and reports its following problems: (1) There is a simple necessary and sufficient condition that makes a number of secret keys invalid; (2) It is insensitive to the change of the secret key; (3) It is insensitive to the change of the plain-image; (4) It can be broken with only one known/chosen plaintext; (5) It has some other minor defects. The proposed cryptanalysis discourages any use of the scheme in practice.

关键词： Cryptanalysis Encryption Hill cipher Known-plaintext attack Chosen-plahltext attack

A New Synthetical Model of High-Power Pulsed Laser Ablation

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Communications in Theoretical Physics 2007年第7期48卷 163-168页

作者： ZHANG Duan-Ming FANG Ran-Ran LI Zhi-Hua guan Li LI Li TAN Xin-Yu LIU dan LIU Gao-Bin HU De-Zhi department of Physics,Huazhong university of Science and Technology,Wuhan 430074,China department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We develop a new synthetical model of high-power pulsed laser ablation,which considers the dynamicabsorptance,vaporization,and plasma *** the corresponding heat conduction equations with the initial andboundary conditions are *** numerical solutions are obtained under the reasonable technical parameter condi-tions by taking YBa_2Cu_3O_7 target for *** space-dependence and time-dependence of temperature in targetat a certain laser fluence are presented,then,the transmitted intensity through plasma plume,space-dependence oftemperature and ablation rate for different laser fluences are significantly *** a result,the satisfactorily goodagreement between our numerical results and experimental results indicates that the influences of the dynamic absorp-tance,vaporization,and plasma shielding cannot be *** all the three mechanisms above simultaneouslyinto account for the first time,we cause the present model to be more practical.

关键词： pulsed laser ablation dynamic absorptance vaporization laser produced plasma